Cosmos Firma

An Unfettered Mind

2012-01-26T12:26:00.000-05:00

I have another book review out, published in the Washington Post on Sunday, January 22. This time the book is Stephen Hawking: An Unfettered Mind, by science writer Kitty Ferguson. It's a new edition of an earlier biography of Hawking that Ferguson published in 1991.

Radioactive

2011-11-30T19:50:00.001-05:00

Check out my latest book review, published in the Washington Post on November 13. The book is titled Radioactive. It's an intriguing, visual work about Madame Curie and her husband Pierre. The author is Lauren Redniss, who is both a writer and artist. Each skill is on beautiful display in this unusual presentation. Below, a sample of two of its 210 pages.

Fried Egg Nebula

2011-09-28T06:00:00.000-04:00

Does the universe want bacon with that?

Fried Egg Nebula

An international team of astronomers recently used the European Southern Observatory's Very Large Telescope in Chile to capture a unique picture of a hypergiant star situated about 13,000 light-years from Earth in the direction of the constellation Scorpius. For obvious reasons, they've playfully named it the Fried Egg Nebula.

This humongous yellow star shines half a million times more brightly than our Sun (is there a sunblock strong enough?) and is a thousand times bigger. If it replaced our Sun, this 20-solar-mass star would almost engulf Jupiter. Earth would be toast.

This star is quite active, hence the two spherical shells of dust and gas that surround the central star, setting up the fried-egg appearance. This material was jettisoned outward in a series of explosive bursts over the last few hundred years. When this hypergiant finally dies as a brilliant supernova some day, watch out!

Image Credit: ESO/E. Lagadec

Who Gave the Black Hole Its Name?

2011-08-15T12:56:00.004-04:00

John Wheeler in Black Hole, Nova Scotia, 1981

Book after book attributes the phrase "black hole" to the Princeton physicist John Archibald Wheeler, who in the 1960s re-energized the field of general relativity by helping prove that if certain dying stars were massive enough they would not settle down as neutron stars but continue to collapse to a point, digging a pit into space-time.

Wheeler liked to tell the tale that he first used the term at a 1967 conference, quickly set up at the NASA Goddard Institute for Space Studies in New York City once pulsars were discovered. Were the pulsars' mysterious beeps coming from red giant stars, white dwarfs, neutron stars? Wheeler told the assembled astronomers they might be the "gravitationally collapsed objects" that he studied. “Well, after I used that phrase four or five times, somebody in the audience said, ‘Why don’t you call it a black hole.’ So I adopted that,” Wheeler told me. He used the phrase again several weeks later during an after-dinner talk at the annual meeting of the American Association for the Advancement of Science (AAAS) in New York City on December 29, 1967. It made it into print when an article based on that talk, titled “Our Universe: The Known and the Unknown,” was published in American Scientist in 1968.

But it turns out the term was already in the air. It had been circulating among conferees four years earlier at a symposium on relativistic astrophysics held in Texas at the end of 1963. The proof? Life magazine science editor Albert Rosenfeld mentioned black holes in his report on the conference. And the term was used again a few weeks later at the 1964 American Association for the Advancement of Science meeting held in Cleveland. Ann Ewing of Science News Letter reported that astronomers and physicists at the conference were suggesting that “space may be peppered with ‘black holes.’”

But it's certainly true that the phrase didn’t catch fire until 1967. It seemed to need the imprimatur of John Wheeler, the dean of American general relativity, to give it gravitas. Once Wheeler gave his blessing, the phrase began popping up in the official scientific literature—although over the first year it was usually denoted as “the black hole,” an expression so exotic it needed to be constrained within quotation marks.

Only Your Astrophysicist Knows for Sure

2011-07-06T06:00:00.013-04:00

Is the universe planning to turn blonde?

The Rho Ophiuchi star formation region

Using a telescope perched high in the Chilean Andes, an international team of astronomers discovered molecules of hydrogen peroxide, the chemical that bleaches hair, in a dense cloud of gas and dust near the star Rho Ophiuchi some 400 light-years distant.

This find is more than an amusing curiosity. Hydrogen peroxide is formed when two hydrogen atoms link up with two oxygen atoms (H₂O₂), a pair of elements critical for life. Moreover, take just one oxygen out of hydrogen peroxide and you get water (H₂O). So, further study of this molecule's chemistry out in deep space may help astronomers better understand the formation of water in the universe.
Image Credit: ESO/S. Guisard

The Ever-Changing Record

2011-06-29T13:00:00.006-04:00

I smiled when I heard the news. An international team of astronomers has just announced the discovery of the most distant quasar, the luminous core of a young and active galaxy situated a whopping 12.9 billion light-years away. That means the light from this quasar, likely generated as matter falls into a supermassive black hole, started on its journey just 770 million years after the Big Bang.

This image of the record-setting quasar, ULAS J1120+0641, was
created from images taken from surveys made by both the Sloan
Digital Sky Survey and the United Kingdom Infrared Telescope Deep
Sky Survey. The quasar appears as a faint red dot close to the center.

I smiled because this headline has been regularly appearing in the news for nearly half a century, ever since Caltech astronomer Maarten Schmidt recognized the first quasar in 1963. Known as 3C 273, from its listing in a catalog of radio sources, Schmidt's quasar was about 2 billion light-years distant: small potatoes now but a huge cosmic distance in its day.

Over the years, the most-distant-quasar record has gotten replaced as often as a newborn's diapers. But now the distances are so great that they present some problems: the light from this newfound quasar suggests that the quasar is being powered by a black hole about two billion times more massive than our Sun. How did such a gargantuan object grow so quickly in the early days of the universe? As team member Daniel Mortlock, of Imperial College London, notes, "It's like rolling a snowball down the hill, and suddenly you find that it's 20 feet across!" Theorists will surely be putting on their thinking caps to find a way.

Chicken or the Egg Question Answered?

2011-06-15T13:00:00.031-04:00

One of the most fascinating findings in astronomy over the last decade has been the unique relationship between galaxies and the supermassive black holes lurking in their centers. Rather than being rare, a giant black hole appears to reside in each and every elliptical or spiral galaxy throughout the cosmos.

Illustration of an active, supermassive
black hole in a galaxy's center

But which came first? The giant black hole, drawing in material to help form the galaxy, or did the galaxy form first, generating the environment for a dense collection of matter to collapse into a black hole at its heart?

Astronomers and theorists from Yale, Rutgers, and the Universities of Hawaii and Michigan have now gathered evidence suggesting that each galaxy and its black hole grow in tandem, starting less than a billion years after the Big Bang. As reported in the journal Nature, the team revealed this by looking at some 250 distant galaxies earlier spotted by the Hubble Space Telescope and searching with the Chandra X-Ray Observatory for the x-ray signals being emitted from each galaxy's central black hole. What they find is a distinct connection: the black holes growing and evolving over time along with their host galaxies. "This finding," says team member Kevin Schawinski of Yale University, "tells us there is a symbiotic relationship between black holes and their galaxies that has existed since the dawn of time."
Image Credit: NASA Goddard Space Flight Center

In a Grain of Sand

2011-04-05T17:46:00.001-04:00

There is something new under the Sun. And it took some 42 years to find it.

In 1969, members of the Japanese Antarctic Research Expedition found nine meteorites lying on an icy field in the continent's Yamato Mountains. Ever since, these specimens (along with the 40,000 meteorites collected in Antarctica afterward) have been avidly studied. Yet, even after four decades of analysis, some surprises remained.

U.S. field team in Antarctica searching for meteorites in 1988-89.

One of the 1969 meteorites, known as Yamato 691, was recently examined with a transmission electron microscope located at NASA's Johnson Space Center in Houston, Texas. This 21st-century nanotechnology allowed researchers from the United States, South Korea, and Japan to zoom in on isolated grains in the meteorite that are less than a hundredth the width of a human hair. And what they discovered was an entirely new type of mineral, different from the 4,500 minerals already recognized by the International Mineralogical Association. The researchers dubbed it "Wassonite," in honor of UCLA professor John Wasson, an international meteorite expert.

Wassonite is made out of only two elements, sulfur and titanium. Yet these atoms join up to form a crystalline structure that has not been previously observed in nature. The mineral formed some 4.5 billion years ago, likely as part of an asteroid orbiting between Mars and Jupiter. Further study of the novel crystal promises to offer new insights on conditions in the early solar system. "In the words of the great English poet William Blake," says Simon Clemett, a space scientist at the Johnson Space Center and co-discoverer of the new mineral, "we are now able 'to see the world in a grain of sand.'"
Picture Credit: Department of Earth and Planetary Sciences, Washington University in St. Louis

Astrobites

2011-03-09T12:36:00.001-05:00

A common refrain from my science-writing students is, "Where do you get story ideas?"

A good place to start is hanging out with graduate students and post-docs, who are often thinking and working on problems at the cutting edge. Many of my best magazine articles when I was starting out involved the work of these pioneering newcomers (many of whom are now the leading lights in their fields).

If those interested in writing on astronomy can't make a personal university visit to find out what's on a graduate student's mind these days, there's a new website that offers the next best thing: Called "astrobites," it's a daily astrophysical literature journal written by graduate students for undergraduates. It beautifully fulfills its named mission―providing up-to-date summaries of the latest research in easy-to-go-down write-ups. The graduate students who post these reports―from Harvard, Michigan, UC Santa Cruz, Colorado, Arizona―aim to make active research areas enticing and accessible to undergraduates, but it serves just as well as a convenient overview for journalists seeking hot new topics popping up in the field of astronomy and astrophysics.

Christmas Tree Nebula: Here just because it's pretty.

Cosmic Target Practice

2011-02-09T15:12:00.002-05:00

When new astronomical images come across my desk, most are often variations on a theme: something I've seen before, perhaps with better resolution or a few new features. But today I was wowed. Astronomers using both the Chandra X-Ray Observatory and the Hubble Space Telescope created a composite image of a celestial object known as Arp 147, which appears like the mother of all bull's-eyes. The universe has pretty good aim when shooting at a target.

The Cosmic Bull's-Eye: Arp 147

On the left in the image above, you see an elliptical galaxy that millions of years ago passed right through what used to be a spiral galaxy on the right. All that remains of that spiral, located some 440 million light-years distant, is a massive ring of stars. The collision triggered a tsunami of star formation that raced around the ring. The ring is so bright in X rays that astronomers conclude that many of those newly-formed stars were likely quite massive. Consequently, they lived fast and died young, exploding as luminous supernovae and leaving behind both neutron stars and black holes. What a sight.

In Honor of John Huchra

2011-01-27T16:23:00.002-05:00

John Huchra, a veteran astronomer based at the Harvard-Smithsonian Center for Astrophysics (CfA), unexpectedly died last fall at the age of 61. To honor his legacy, his friends and colleagues have now set up on the interactive website WorldWide Telescope a special tour titled, appropriately enough, "John Huchra's Universe." I highly recommend taking a look. To get instructions on how to access the tour on the WorldWide Telescope (or where to go to view a non-interactive version on YouTube), click here.

Watching the program brought back many memories for me, for John provided me with one of my first "scoops" in science journalism. In 1985 he and his collaborator Margaret Geller allowed me to get an early peek at their latest finding: a map of galaxy redshifts, taken through a narrow slice of the sky, out to more than half a billion light-years. It showed that galaxies are not smoothly distributed through the universe but instead congregate to form gigantic, nested bubbles—a cosmic foam. Inside the bubbles were equally huge voids. This wasn't a celestial architecture that anyone was expecting. It was big news. I wrote a story on it for Science Digest, a report timed to coordinate with John and Margaret's discovery announcement at the 1986 annual meeting of the American Astronomical Society.

The original 1986 CfA map of galaxy distributions

Theorists now believe that the bubblelike structures were forged when pressure waves moved through the early universe's hot primordial plasma, creating regions of compressed and rarefied matter. This led to galaxies forming predominantly in the areas of compression and the less dense voids enlarging over time and remaining relatively empty. Geller likened the distribution to a "kitchen sink full of soapsuds."

Over the succeeding decades, astronomers have enlarged this map extensively. Here's a look at the Two-Degree Field Galaxy Redshift Survey carried out in the 1990s that extends out to two billion light-years:

Each point in the image represents a galaxy—tens of thousands overall in two slices of the sky

Rings of Fire

2011-01-05T11:52:00.000-05:00

Over Christmas, two space telescopes—the European Space Agency's Herschel and XMM-Newton observatories—took a look at our closest spiraling neighbor, the Andromeda galaxy situated more than 2 million light-years away. It puts Andromeda in a whole new light....literally. The Herschel, which gathers invisible infrared light, detected intriguing rings of dust encircling the galaxy's center. Some speculate that these dust rings, not fully seen in the optical, may have formed from a past collision with another galaxy. Within these dusty circles, multitudes of new stars are forming.

Andromeda galaxy in infrared; x-ray sources in blue

Meanwhile, the Newton x-ray telescope spotted hundreds of x-ray sources (the blue dots in the picture) smack dab in the center. Some are the debris from exploding stars; others are stars in close binaries getting their mass pulled off by the intense gravitational pull of their denser partners. The x rays are given off from the intensely heated matter. What a show! Stellar birth and death, captured in one intriguing image.
Picture Credit: European Space Agency

Let the Sunshine In

2010-12-21T00:01:00.001-05:00

Today is the Winter Solstice. You may be lamenting the official start of winter (coincidentally the Boston area is now getting its first snowfall of the season), but I'm rejoicing. Starting today, and continuing over the next six months until the summer solstice, our daylight hours will be growing by roughly two minutes each day. Alleluia—the sun is coming back to us here in the northern hemisphere.

And to put the cherry on the sundae, we get a lunar eclipse on the same day. That hasn't happened since December 21, 1638. Sir Isaac Newton wasn't even born yet. That came four years later.

Evidence for Tiny Black Holes?

2010-12-09T11:32:00.000-05:00

Last month some astronomical news came out that didn't get much play, but I was fascinated by it. UCLA scientists are claiming they might have detected evidence for primordial black holes, tiny cosmic denizens first predicted by Stephen Hawking in the 1970s. If that's true, it's pretty big news, as here would be a means to study what happens when general relativity meets quantum mechanics—the holy grail of physics these last few decades.

What Hawking did was ask how a black hole might affect its surroundings from the viewpoint of an atom. He concluded that space-time gets so twisted near a black hole that it enables pairs of particles (a nuclear particle and its antimatter mate) to pop into existence just outside the black hole. You could think of it as energy being extracted from the black hole's intense gravitational field and then converted into matter. At times, one of the particles disappears into the black hole, never to return, while the remaining one flies off. As a result, the hole's total mass-energy is reduced a smidgen. This means the black hole is actually evaporating!

Illustration of primordial black hole's final evaporation

For stellar-size holes, this bizarre quantum-mechanical process is just about meaningless. It would take trillions upon trillions of years for a regular black hole to shrink away to nothingness. But Hawking suggested that the early universe, in the first turbulent moments of the Big Bang, might have manufactured a multitude of tiny black holes. The smallest would have vanished by now, but objects containing the mass of a mountain, yet compressed to the size of a proton, would be shedding the last of their mass at this very moment in a short and spectacular burst of gamma rays.

That's what the team of UCLA scientists, led by David Cline, believe they are seeing. Looking over data from a number of gamma-ray telescopes, they have detected gamma-ray bursts lasting less than 100 thousandths of a second. That's the type of signal expected from the evaporation of primordial black holes. Of course, such signals could be also be arriving from a more common stellar process not yet identified. As Carl Sagan liked to say, "Extraordinary claims require extraordinary evidence." Cline agrees. He's urging others to start studying these events as well, to see if their claim holds up to scrutiny.
Image Credit: Virginia Tech Department of Electrical and Computer Engineering

When You Wish Upon Some Stars

2010-12-02T12:05:00.000-05:00

When you woke up this morning, did the universe seem a bit more crowded? Well, you were right.

A team of astronomers, led by Yale University's Pieter van Dokkum, has announced that the cosmos likely harbors up to three times more stars than previously assumed (it may be less). Our stellar elbow room is getting squeezed.

Illustration of planet near a red dwarf star

Why didn't we know this before? Because the stars missed in earlier surveys are red dwarf stars, the tiniest and faintest of all stars. The optical signature for these missing stars was discovered in several elliptical galaxies near the Milky Way galaxy. According to the astronomers who made this discovery, elliptical galaxies, which resemble giant eggs, somehow house far more red dwarfs than spiral galaxies, such as the Milky Way. And by assuming this new cache is true for all elliptical galaxies in the universe, that ups the total stellar population by quite a bit.

That's good news for Jiminy Cricket. When he now wishes upon a star, he'll have a lot more to choose from.

Going Loony

2010-11-16T13:45:00.001-05:00

For years it drove me mad. I guess I should say "loony." But I'm starting to get used to it, resigned to the fact that some cartoonists just don't know their astronomy. You've seen it: those crescent moons, whose "horns" are pointing the wrong way, like in the Mickey Mouse comic below.

Moon's wrong

Think about it.....the moon gets its glow from the Sun. And if the Sun is lighting the Moon from the top, it would be up in the sky and it wouldn't be night!

Now, I have to contend with these astronomical errors when trying to relax with a good book. There I was, immersed in a historical novel about the 15th century English Plantagenets, when the author mentions the "waning moon rising off the horizon" at dusk.

Waning Crescent Rising at Sunrise

Completely wrong. In that era of pitchblack nighttime skies, the Plantagenets themselves would be keenly aware how the Moon waxed and waned every four weeks—a waning Moon has its "horns" pointed up as it's rising in the East (as in the picture to the right). That means it's being lighted up from the Sun just below it. But, according to the novel, it's dusk, so the Sun has to be setting over on the other horizon in the west! It can't be rising in the east at the same time.

Waxing Crescent Setting at Sunset

The author should have done their homework: a waning crescent Moon rises just before dawn, not at sunset. It is a waxing crescent Moon that is seen in the early evening. But it is not rising; it is setting in the west.

How sad that in just a few short centuries, we've lost touch with the rhythms of the heavens.

Dark Matter Made Visible

2010-11-11T13:23:00.002-05:00

I've been chasing the elusive dark matter story in astronomy for some twenty-seven years now, ever since I did an article on the "missing mass" in the (now defunct) Science Digest magazine in 1983. I followed up with a book, Through a Universe Darkly, a decade later. I haven't tired of the subject and still avidly follow each new clue that appears on the scene. It's mind-boggling that around 85 percent of the matter in the universe is in a form that remains invisible.

The latest evidence comes from the Hubble Space Telescope (HST). A team of astronomers led by Dan Coe of NASA's Jet Propulsion Laboratory recently aimed a HST camera at a massive galaxy cluster known as Abell 1689, located more than two billion light-years away. While astronomers can't see dark matter, they can certainly view its gravitational effects, especially in the way dark matter diverts light passing through the universe. You might think of the dark matter in the cluster as a massive stone with the light passing by acting like a stream of water that comes upon the rock and is split into two or more streams. In other words, dark matter bends light arriving from the distant galaxies behind it, much like a lens (which is why the effect is called "gravitational lensing"). What results is a funhouse view of the cluster, filled with myriad arcs, bands, and rings of light. The amount of light bending provides the means to "weigh" the dark matter in the cluster.

This is not a new approach. Abell 1689, due to its rich collection of galaxies, has been studied for years in this way. But this latest image is the highest resolution yet, which enabled the astronomers to map the dark matter's distribution within the cluster.

Galaxy Cluster Abell 1689, located 2.2 billion light-years distant

Each spot in this picture is a far-off galaxy, not a star. The Abell 1689 cluster contains about 1,000 galaxies in all. The light blue haze has been artificially added to indicate where the dark matter is concentrated within the cluster.
Image Credit: NASA, ESA, and Z. Levay (STScI)

Capturing Primordial Starlight

2010-11-01T13:31:00.003-04:00

Edwin Hubble at 100-Inch

By 1936, Edwin Hubble was a dozen years into his search for distant galaxies. At that time, he could see out to several hundreds of millions of light-years, using the great 100-inch telescope atop California’s Mount Wilson. But even then the smudges on his photographic plates were dim, fuzzy, and next to impossible to identify.

“There,” wrote Hubble in his classic book The Realm of the Nebulae, “we measure shadows and…search among ghostly errors of measurement for landmarks that are scarcely substantial.”

Ever since, astronomers have struggled to trace the evolution of galaxies back through space-time—not just hundreds of millions of light-years but billions. For decades, all that astronomers could say with surety were that distant galaxies and clusters looked a bit “bluer,” a sign of heightened star formation as hoards of young, massive stars, flush with energy, put out more blue light.

Quasars, the brilliant cores of newborn galaxies, had long been sighted at great distances, but astronomers questioned whether they could truly understand the early universe by studying only its most active members.

But thanks to key technological breakthroughs over the last two decades—among them, the Hubble Space Telescope, the opening of giant telescopes in Hawaii and South America, and advances in telescopic detectors—more typical primordial galaxies are now being found, and at greater and greater distances.

UDFy-38135539 (circled in red) lurks within the Ultra Deep Field

The current record holder was recently discovered by a European team of astronomers using the European Southern Observatory’s Very Large Telescope (VLT) in Chile. It’s but a speck in the image, but a sensitive spectrograph allowed the observers to peg its distance. It’s more than 13 billion light-years from Earth and has been christened UDFy-38135539. That’s a mouthful for us but helpful to astronomers: the UDF stands for Ultra Deep Field (a region located in the southern-hemisphere constellation Fornax that was first closely imaged by the Hubble Telescope) and the number pegs its precise position on the sky.

The photons from this distant object started their journey when the universe was only 600 million years old. This was a time when a great fog of hydrogen gas, in which the universe was bathed, was just beginning to break up—cleared out by the fierce ultraviolet light emitted by newborn galaxies. The VLT likely sighted the new record holder through a break in the clouds, a lucky event for the astronomers and for us. Through this fortuitous window, we get to see a bit of primordial starlight.

Picture Credits: (top) Huntington Library; (bottom) European Southern Observatory

The Nobel Prize That Got Away

2010-09-27T10:37:00.002-04:00

Sometimes a great scientific idea needs time to take root. Sometimes the world simply isn’t ready. Continental drift comes to mind as an example, as well as germ theory. Continents moving around, microscopic bugs? Each of these propositions seemed too bizarre to accept right off. In such situations, scientists have to be convinced that a new concept is worth looking into.

Astronomy is no exception. A famous case is a cosmic prediction that first appeared in a 1948 scientific paper almost as an afterthought. Soon forgotten, it took years before the conjecture turned into cosmology’s greatest tool.

At the time scientists were grappling with a tough question: how did the universe come to manufacture its vast array of elements? Previous to this, everyone just assumed that matter always was and would always be, but revelations coming out of atomic physics laboratories—from radioactivity to nuclear transformations—in the first half of the 20th century completely altered that notion. The elements obviously came from somewhere. The most plausible factory was inside a star, but no physicist in that era could get stellar models to build an atom heavier than helium. Anything more weighty quickly disintegrated within their theoretical computations.

George Gamow

What to do? The Russian-American physicist George Gamow in 1942 simply looked around for another locale for cooking up the elements, and he found one in the “primordial atom,” the relatively new idea that the universe had emerged and expanded from an initial, hot plasma. (The term Big Bang didn’t arrive until 1949.)

Ralph Alpher

As Gamow’s graduate student at George Washington University in the mid-1940s, Ralph Alpher took on the challenge for his doctoral thesis and theoretically demonstrated how it could be done. Like some skilled astrophysical chef, he started with a highly compressed stew of neutrons that he dubbed ylem, after an ancient Greek word for the basic substance out of which all matter was derived. As the temperature of the cosmos began to plunge, some of these particles decayed into protons, which promptly began to stick to remaining neutrons. Step by step, each element was built up from the one before it—from helium to lithium, lithium to beryllium, beryllium to boron, and so on down the periodic table. In less than half an hour, when the last of the free neutrons decayed away, the cosmic meal was complete, with Alpher and Gamow concocting the full complement of universal “flavors,” all the way up to uranium.

Their first report on this finding, a one-page synopsis published in Physical Review, is more famous for its byline than its content. Gamow, a merry prankster, listed the paper’s authors as Alpher, Bethe, and Gamow, even though noted physicist Hans Bethe never participated in the work. Gamow couldn’t resist the pun on the first three letters of the Greek alphabet: alpha, beta, gamma. That the paper chanced to be published on April Fool’s Day in 1948 only added to the fun.

The twenty-seven-year-old Alpher had been working at the Applied Physics Laboratory of Johns Hopkins University where, upon earning his PhD, he continued to collaborate on Gamow’s campaign to study the physics of the Big Bang model, joined by fellow APL employee Robert Herman. There the two young scientists went on to develop a detailed evolution of the newborn universe, work later described by physicist Steven Weinberg as “the first thoroughly modern analysis of the early history of the universe.”

Robert Herman

In their investigations, the pair eventually came to realize that Alpher’s original recipe for elemental cooking had a tragic flaw: while his scheme could make a few light elements, the cosmic expansion both dispersed and cooled the primordial plasma before the heavier elements had any chance of forming. With better stellar models, others would later prove that stars could do the job after all. But no matter. In the course of their work, Alpher and Herman made a historic calculation that has stood the test of time.

This result was revealed in an unusual manner. On October 30, 1948, Gamow had published an article in the British journal Nature titled “The Evolution of the Universe.” But in checking over Gamow’s reported results, Alpher and Herman found some errors. They soon dashed off a correction, a brief letter to the editor only four paragraphs long that was published within two weeks. With their more accurate figures, Alpher and Herman compared the density of matter to the density of radiation as the universe evolved. In doing so, they curtly noted at the end of their letter that “the temperature in the universe at the present time is found to be about 5° K [five degrees kelvin].” That’s a mere five degrees above absolute zero (− 459.67° Fahrenheit), the point at which all motion ceases.

With little fanfare, Alpher and Herman were telling the world that the present-day universe is bathed in a uniform wash of radiation leftover from the flood of highly energetic photons released in the fury of the Big Bang. Cooled down over the eons with the expansion of the cosmos, the waning fire now surrounds us as centimeters-long radio waves. Today it is known as the cosmic microwave background radiation (CMBR).

When their note was published, the primordial atom theory was still highly controversial. Many astronomers preferred the steady-state model of the universe, a theory that postulated that space-time had neither a beginning nor an end. But Alpher and Herman’s calculation was a clear-cut means of deciding between the two opposing theories of the universe’s behavior. Yet no one followed up. Looking back, it’s hard to fathom why astronomers didn’t jump at the chance at pointing their instruments at the sky to capture this primordial whisper of creation. But some thought radio telescopes weren’t yet sensitive enough for the task, and when a few did peg an overall temperature of interstellar space at around 3 kelvin, they didn’t link it to cosmology at all. Some thought it was an error in their instruments.

Radio astronomers may have been unresponsive because their field was just establishing itself after World War II and cosmological tests were not taken seriously. As Weinberg noted, they “did not know that they ought to try.” The radio sky was all so new. There were too many objects—radio stars, radio nebulae, radio galaxies—grabbing their attention. Amid such distractions, Alpher and Herman’s prediction was either dismissed or utterly overlooked. The two tried pumping up interest—at one point even holding a press conference to generate attention. But since both men later went into industrial research, they didn’t have the opportunity to keep pushing astronomers to take a look.

The idea didn’t resurface until 1964-65, when astrophysicists at Princeton University again reasoned that the Big Bang’s residual heat must be permeating the universe (with no mention in the team’s Astrophysical Journal paper that Alpher and Herman did it first). Two Bell Lab researchers, Arno Penzias and Robert Wilson, accidentally detected the primeval microwaves with a horn antenna in New Jersey as they were preparing to study our galaxy. For this achievement, Penzias and Wilson received the 1978 Nobel Prize in Physics.

Herman died in 1997, Alpher ten years later. Both were deeply pained that the scientific rewards for making their momentous prediction never came to pass for them—election to prestigious academies, sizable research grants, prized promotions. The honors that were bestowed (Alpher received the National Medal of Science in 2005) arrived late. “But we should not indulge in sermonizing about the nature of science,” the two noted about this oversight in a scientific memoir of their work published in 2001. “On to more about the CMBR….” And so I shall.

Over the last two decades detectors in space have measured the cosmic microwave background, now pegged at 2.7° K, in exquisite detail. By mapping the barely perceptible ups and downs of this signal, across the breadth of the celestial sky, astronomers have revealed a wealth of cosmological information: they’ve viewed the quantum jiggles that led to galaxy formation, tallied the exact amount of ordinary matter contained in the universe, verified that there is five times more cosmic stuff of an unknown nature (called dark matter), and confirmed that space-time is permeated with an energy that is causing the universe to not just steadily expand but accelerate outward like a runaway drag racer.

And to think, all this knowledge was gleaned from a radio murmur, a faint heat first mentioned unceremoniously in a note tucked away on the back pages of a scientific journal sixty-two years ago.

Belly Up to the Bar

2010-09-23T09:21:00.001-04:00

What would inhabitants of the Andromeda galaxy see when they peer at the Milky Way through their extraterrestrial telescopes? In illustrations and planetarium shows, you often see our home galaxy depicted much like the picture to the left: a bright and round central bulge, surrounded by feathery spiraling arms.

But that's not the case. More and more evidence is gathering that the Milky Way is actually a "barred spiral"—in other words, a galaxy with a straight bar of stars running through its center. In fact, the Milky Way probably looks a lot like NGC 1365, a grand barred spiral some 60 million light-years distant that just had its picture taken (to the right) with a new infrared camera mounted on the European Southern Observatory's Very Large Telescope in Chile.

Does that mean the Milky Way and NGC 1365 are special? Not at all. Astronomers estimate that around two-thirds of all spiral galaxies display a barred structure. By looking at NGC 1365, we get a peek at the architecture of our own cosmic home.

Night = Day

2010-09-22T00:00:00.009-04:00

Here in the northern hemisphere, the sun is crouching lower in the sky, the nights are getting longer, and the trees are beginning to turn a spectrum of colors.

Today begins the last quarter sprint towards winter. Happy Autumnal Equinox everyone, the moment when the hours of the day equal the hours of the night (well, give or take a few minutes).

King of the Sky

2010-09-14T16:28:00.001-04:00

After the August doldrums and a dearth of posts on this blog, the cooler and refreshing air of autumn promises to energize me. Even the nighttime sky is displaying more vivacity these days.

Lately, Jupiter, top god in the Roman pantheon, is living up to its reputation. Look to the east after twilight and you will see the solar system's biggest planet brilliantly dominating the celestial landscape. According to Robert Naeye, editor-in-chief of Sky & Telescope magazine, Jupiter is "making its closest pass by Earth for the year. And this year's pass is a little closer than any other between 1963 and 2022." The night of closest approach is Monday, September 20, just two days before the autumnal equinox. (The picture below depicts Jupiter and the Moon as they will be in the evening sky on September 22. Click on it for a closer look.) At that point, Jupiter will be a mere 368 million miles from Earth.

So, step outside tonight. Take a look to the east. Jupiter won't be this bright again for another 12 years.
Picture credits: Voyager 2 and University of Arizona Science Center

Third Age of Discovery

2010-07-31T10:31:00.000-04:00

My latest book review, published in the Washington Post, Sunday, August 1.

VOYAGER: Seeking Newer Worlds in the Third Great Age of Discovery

By Stephen J. Pyne

Viking. 444 pp. $29.95

For those 30 or younger, the journey is now ancient history, having originated before they were born. As summer was coming to an end in 1977, two spacecraft were launched from Cape Canaveral, Fla., outfitted with a bevy of instruments to take a grand tour of the outer planets. NASA was taking advantage of a planetary alignment that comes only once every 176 years. Stephen Pyne chose now to write about these probes, Voyager 1 and 2, because he views them as potent symbols of a third great age of discovery.

The earlier eras were forged by European rivalries—first the great oceanic explorations during the Renaissance and then the more scientific ventures in the 18th and 19th centuries, such as Darwin's voyage on the Beagle. But the third epoch transcends "anything humanity has known before," Pyne writes. "It would reach beyond sordid politics and the blinkered ambitions of its originating time and place."

That's a weighty mantle for Voyager to wear, I thought upon starting the book. Why not choose, as the avatars of this age, the robots roving over Martian deserts or the Apollo program that took men to the moon? Pyne, an environmental historian at Arizona State University, answers that question—and much more—in this fascinating and beautifully written chronicle. Much like Ferdinand Magellan's bold, world-spanning journey, Voyager was one of those "moments of exploring that . . . fuse place, time, discovery, and yearning." The Apollo program, contends the author, "went nowhere, withdrawing to the virtual solipsism of the space shuttle and a near-Earth space station." But the Voyagers found new moons, planetary rings, erupting volcanoes and potential sites for extraterrestrial life. It was the grand gesture.

Despite the title, Voyager is not a detailed, straightforward account of the project. What makes this book unique is Pyne's combination of history and philosophy as he reflects on the role of exploration in human society. Throughout its pages, the Voyagers' passage through the solar system is compared and contrasted with terrestrial expeditions of the past. Even the most passionate aficionado, who devoured every digital bit sent back by the Voyagers, will find this overview enriching.

Occasionally a comparison can be prosaic (in volume, each Voyager was roughly equivalent to Columbus's Niña), but more often they are poetic and engaging. A Voyager rounding Jupiter, for example, is likened to Vasco de Gama swinging around the Cape of Good Hope. Only this time we found "hurricanes the size of Earth's Moon that lasted for centuries; stormy eddies that roiled past like boiling Mississippis; trade winds that would shred and crush sailing ships." De Gama caught the austral westerlies to hurl him past Africa; the Voyagers were boosted gravitationally as they sailed from planet to planet.

Once Voyager 1 flew past Jupiter and Saturn, it headed out of the solar system. It was Voyager 2 that completed the full grand tour, arriving at Uranus in 1985 and Neptune in 1989, so far out that it took four hours for its data to reach Earth. Remembering only the glorious images, I was surprised to learn how close the Voyagers came to disaster in flight—jammed platforms, misdirected antennas, failed receivers—all either fixed or worked around by ingenious engineers. For that matter, before launch some scientists argued against including cameras at all, believing them a waste of payload. Thankfully, others prevailed, perhaps taking a lesson from the second age of discovery, when Thomas Moran's stunning paintings of Mammoth Hot Springs helped push Congress to declare Yellowstone a national park. Those remaining home want "not just shared data but shared meaning: not merely the eyes of discovery but its poetry," writes Pyne.

According to Pyne, the golden era of the third age is now turning to silver, where more focused work replaces inspiration: The Magellan probe goes to Venus, Galileo to Jupiter, Cassini to Saturn. What comes next is difficult to predict: Perhaps millions will gain the opportunity to virtually explore, as technology progresses. Or maybe there will be renewed competition among spacefaring nations, harking back to the first age.

Whatever the outcome, the Voyagers are still on the job. Now past Pluto, the stalwart pair are "sounding" the depths of space and have enough power to send back their findings until 2020. Only last year the probes detected the presence of magnetic fields that are holding together an interstellar cloud through which the solar system is now passing.

Hardly ancient history after all.
Picture: An artist's conception of Voyager 1's encounter with Saturn. (NASA/Associated Press)

Slaughterhouse 2001: A Da Vinci Odyssey

2010-07-23T13:35:00.001-04:00

A column by Alex Beam in the Boston Globe this morning sparked me to visit the website called "I Write Like" (http://iwl.me/). As Beam noted, paste a sample of your writing into its analyzer and, shazam, it tells you what famous author your text most resembles. I seemed to morph into different writers, depending on what I put into it. According to its statistical wisdom on word choice and style, the chapters of my latest book, The Day We Found the Universe, are similar to prose by Arthur C. Clarke (below on left), Kurt Vonnegut (center), and Dan Brown (right). If only that translated into comparable sales!

P.S. This particular blog entry, says the website, could have been written by Vonnegut (must be that shazam).

Summer Mourning

2010-06-22T19:40:00.003-04:00

Summer Solstice arrived yesterday at 7:28 in the morning Eastern Daylight Time. I'm wearing black.

For most people, the first day of summer marks a season of celebration: sun, sand, fireworks, and outdoor fun. But for me I'm disheartened. I can only dwell on the fact that for the next six months, here in the northern hemisphere, the days will be getting shorter and shorter. We mark the start of summer on the longest day of the year. After that, it's downhill for us light lovers. With each passing day, we lose two more minutes of sunlight, meaning two more minutes of night until December 21, when it turns back around.

The Winter Solstice offers far more to look forward to.
Image Credit: JustUs3 at Flickr

Hawking Radiates

2010-06-08T11:11:00.003-04:00

I recently attended the World Science Festival in New York City, moderating a panel on gravity-wave astronomy. With the gig came an invitation to attend the opening gala at Lincoln Center in honor of physicist Stephen Hawking.

It was a delightful cultural evening, blending science with music, video, and dance. Skipping the post-gala reception, my husband and I walked back to our hotel to have a late dinner. Toward the end who should come into the dining room but Hawking himself with a group of colleagues, including Caltech physicist Kip Thorne. Kip invited us over for after-dinner drinks, where I at last was able to meet Hawking in person.

Over my thirty years covering the fields of physics and astronomy, I have often written on Hawking's work. I pointed out to Stephen that I had reviewed his science-book sensation, A Brief History of Time, for the New York Times when it was first published in 1988. But I also made a confession. Most book reviewers receive the manuscript of a book months before publication. I was truly giving a fresh perspective, totally unaware of the book's notoriety to come. I told Hawking that, given his fame, I had figured his work would be a science-book best seller. Why it might even sell 20,000 copies!

Silly me. It, of course, sold millions around the world.

Hawking smiled.

Image Credit: Rob Bodman

Heart and Soul

2010-05-24T11:06:00.000-04:00

As you can tell from several of my posts, I'm a sucker for astronomical images, especially those that display swirling ribbons of gas dotted with jewel-like stars, all sweeping across the sable backdrop of night. I find them comparable to the finest abstract art.

The latest is from NASA's WISE surveyor, an infrared telescope in space with a wide-field view. The picture above covers an area of the sky ten times as wide as the full Moon. Captured, with such pleasurable delight, are the Heart and Soul nebulae. The "Heart" is on the left, aptly named for its resemblance to the human heart. It was inevitable that its companion on the right would be pegged the "Soul." They're both part of the Perseus arm of our spiraling galactic home, the Milky Way.

What you are viewing are giant bubbles, formed by the fierce radiation and winds generated by the new stars, less than a few million years old, being formed within the nebulae.

Given that the Cat's Paw nebula mentioned in an earlier post included a poem, this one deserves Frank Loesser's lyrics to the song instinctively plunked out by every would-be musician sitting down at a piano:

Heart and soul, I fell in love with you,

Heart and soul, the way a fool would do,
Madly...

Because you held me tight,
And stole a kiss in the night....

Image Credit: NASA/JPL-Caltech/UCLA

Holey Moley

2010-05-12T11:46:00.002-04:00

An infrared space telescope operated by the European Space Agency found a "hole" in space―a black patch of sky with nothing in it. No stars, no dust, no...anything.

In the 1780s, while sweeping the heavens with his state-of-the-art telescope outside London, astronomer William Herschel first noticed dark regions that appeared to be devoid of stars. One night he was heard to exclaim in his native German, "Hier ist wahrhaftig ein Lock im Himmel! [Here is truly a hole in the heavens], at the sight of a void in the Ophiuchus constellation (image below).

By the early 1900s, though, superb photographs by astronomer E. E. Barnard at the Yerkes Observatory began to prove that such shadowy regions, including the famous Horsehead Nebula and the black spots scattered along the Milky Way, were actually dark absorption clouds, too opaque for starlight to shine through.

And that's been the standard wisdom....until now. In the ESA's infrared image (above) can be seen an actual hole. It's the dark spot in the green-tinged cloud at the top of the picture. Astronomers speculate that it opened up when narrow jets of gas, emanating from some of the young stars in the region, punched through the dust and gas of the glowing nebula known as NGC 1999. The spot is not a black cloud but rather a window on distant space―a true hole in the heavens.

William Herschel had the right idea but was just looking in the wrong spot. How appropriate that the infrared telescope that made this observation is named "Herschel."
Image Credits: B. Wallis and R. Provin (top); ESA/HOPS Consortium (bottom)

On Little Cat Feet

2010-04-28T17:23:00.003-04:00

I prefer dogs to cats. I smile when looking up at Orion in the winter, seeing playful Canis Major in pursuit and Sirius, the Dog Star, shining with its blue-white intensity. But the European Southern Observatory might change my mind with its recent observation of a cool, cosmic feline.

The ESO's Paranal Observatory, situated in Chile's Atacama desert, just released an infrared picture (on the right) of the Cat's Paw Nebula, a vast stellar nursery 5,500 light-years distant in the constellation Scorpius.

The picture on the left is for comparison. It shows the same nebula in visible light. Because infrared light can pass through obscuring dust, the infrared picture reveals a multitude of new stars within the nebula itself. And it also allows the "paw" to stand out more clearly. There's no better time to quote Carl Sandburg's 1916 poem "The Fog":

The fog comes

on little cat feet.

It sits looking

over the harbor and city

on silent haunches

and then moves on.

Picture Credit: ESO/J. Emerson/VISTA

The Envelope Opened

2010-04-26T11:39:00.002-04:00

The Los Angeles Times Book Prize ceremony was held in L.A. last Friday evening, the envelope opened, and another name other than my own was announced as the winner of the best science book. (My book, The Day We Found the Universe, was one of the five finalists.) But I'm far from disappointed, as the winner was very deserving. Graham Farmelo was chosen for his excellent biography of the brilliant physicist Paul Dirac titled The Strangest Man. (Dirac first posited the existence of anti-matter.) I was sorry that I didn't get the opportunity to meet Graham in person. He was unable to fly the Los Angeles for the award ceremony because he's serving on jury duty in Great Britain, where he resides. For his sake, I hope it's an interesting case.

Like a Seven Year Old

2010-04-08T11:25:00.005-04:00

Yesterday I spent a delightful evening sharing the podium with Harvard physicist Lisa Randall at the Cambridge Forum to talk about science and creativity. Here were my opening remarks:

In some autobiographical notes, Albert Einstein remembered being haunted as a lad by a strange thought: If a man could keep pace with a beam of light, what would he see? Would he observe a wave of electromagnetic energy frozen in place like some glacial swell? “It does not seem that something like that can exist,” Einstein recalled thinking at the youthful age of sixteen.

There is a stereotype about creative scientists: they are born geniuses, whose brains are somehow prewired to recognize how nature works. They see a problem and, out of the blue, the answer arrives as if by magic. The science cartoonist Sidney Harris captured this so well in one of his cartoons. He has Einstein standing at the blackboard. At the top Einstein has written, E = ma², but crosses it out. Below it, E = mb², and then crosses that out as well. Well, of course, reality works far differently.

Einstein thought long and hard about that light beam. Creativity did not come easily. He didn’t solve the problem until 1905, when he was twenty-six years old. Einstein’s solution was found by thinking outside the box—questioning the unquestionable. He let go of the familiar and found an alternate route. He had this wonderful ability to embrace new ways of thinking. That often happens in science when a person is young and not yet weighed down by old habits and allegiance to conventional wisdom. A recent experiment even made this point. Two psychologists at North Dakota State University asked a group of undergraduate students to imagine what they would do if school were cancelled for the day. The students’ responses were pretty bland, until they were told to think like seven-year-olds, whereupon the answers became far more original and spontaneous. Likewise, the most creative scientists often retain a childlike curiosity about the world.

By thinking outside the box, Einstein concluded that no one can catch up to a light beam, no matter how fast you go. Even if you’re in a spaceship rocketing away at near-light speed. Which seems bizarre, until you realize, as Einstein did, that space and time are not absolute as Isaac Newton had us think, but rather, well, relative. Our measurements of length and time alter, depending on our motions with respect to one another. The only thing that we will agree on is that light travels at 186,000 miles per second. Moreover, this new idea was backed up by experimental tests. Perhaps creativity in science comes from encouraging heresy.

Creative is usually a term applied more to the arts and humanities than to science. In fact the noun “creativity” originated fairly late, in 1875, to refer solely to poetic imagination—the way in which artists and writers bring new entities into existence. But when applied to scientists, there’s one big difference. Scientists can imagine a lot of things, but unlike artists and writers they are restrained by the rules of the game—the laws of nature that were set into place at the creation of the universe. Their creativity comes into play in the approaches they take in arriving at new theories, which must then be experimentally proven.

There is, of course, no precise path, but many roads. Creativity, for instance, can emerge from the mentor/apprentice relationship, which was beautifully rendered by my colleague at MIT Robert Kanigel in his book Apprentice to Genius, where he describes how recognizing a good problem and how to find a solution to it can be handed down from generation to generation of scientists. Kanigel’s book involved four generations of neuropharmacologists studying drug metabolism and opiate receptors in the brain. Creativity was handed down, as if genetically, from mentor to apprentice. There’s further evidence that certain creative habits can be acquired. J. J. Thomson, the discoverer of the electron and a recipient of the Nobel Prize, himself trained nine Nobel prize winners, as well as 32 fellows of Great Britain’s Royal Society.

What are those habits? Louis Pasteur once said, “In the fields of observation, chance favors only the prepared mind.” Creative scientists are prepared. Legendary discoveries are not lucky breaks but more like unanticipated detours in well-designed research efforts. Take Alexander Fleming. As the legend goes, a stray penicillium mold lands on a bacteria-filled petri dish in his lab. About to discard the dish, he notices the mold has dissolved the bacterial colonies. Voila, antibiotics. But actually Fleming at first noticed only the mold’s mild antiseptic properties. He didn’t clinch that the bacteria were truly being wiped out until further research, after he deliberately cultured the mold. Fleming cast a large net in his lab, experimenting with anything he could find. His creativity came from “playing,” designing experiments that would likely yield surprises.

Creativity can also arise from, what looks to outsiders, like drudge work. Science often involves finding patterns, where none are expected. And that comes from gathering lots and lots of data. We’ve seen that in the human genome project, climate change, Darwin’s development of his theory of evolution, the history of particle physics. Drawing on my own work covering the field of astronomy, a famous example is the work of Henrietta Leavitt. In the 1910s, she was working at the Harvard College Observatory, assigned to examine the myriad photographic plates the observatory was amassing and look out for variable stars, stars that regularly vary in their luminosity—brightening, then dimming, then brightening once again. She did her job well. By the time of her death in 1921, she had discovered some 2,400 variable stars, half the number then known to exist. But she went beyond her job description and noticed, out of the hundreds she was finding, a special group of twenty-five variables, called Cepheids, whose light varied in a specific way: the brighter the star, the slower its period. Tracking the blinks of those variables allowed them to be used as standard candles for gauging distances in space. With her deep concentration and focus on her data, Leavitt unearthed astronomy’s celestial Rosetta stone, a means for astronomers to measure distances far beyond the Milky Way. It was the tool that allowed Edwin Hubble to discover that the Milky Way was not alone in the universe, but rather just one of billions of other galaxies.

More and more creativity, especially in 20th century physics, has been arising from seeking mathematical beauty. And it’s had its successes. In the first half of the 20th century, physicists were finding a chaotic zoo of elementary particles with their atom smashers. They practically ran out of Greek letters to name them all: lambdas, sigmas, pions. “Who ordered that?” exclaimed one theorist when the muon, a heavy electron, was identified. Physicists Murray Gell-Mann and George Zweig independently got order out of this chaos through a mathematical breakthrough. Nearly all of those particles were actually composites, each a different combination of smaller, more fundamental particles we now call quarks. The search for mathematical beauty allowed complexity to be replaced by a wondrous simplicity. But can that be carried too far? Some ask that about string theory, which hypothesizes a submicroscopic world that cannot yet be tested directly.

What will be interesting to track in the future is whether science is getting hampered in its creativity by its overspecialization, fields getting subdivided further and further into niche specialties. Science has blossomed a millionfold since the 1600s, yet we are not witnessing a millionfold increase in the number of fundamental discoveries. Where are the thousands of Newtons, Darwins, and Einsteins that should now be walking the earth given the astounding explosion in scientific publications. Has science become so bureaucratic that it ends up sabotaging those who would discover?

Some believe that new bursts of creative thought will come from interdisciplinary work. Chemists talking more to physicists, biologists with mathematicians. So that skills from each discipline will be communicated and exchanged. Each teaching the other how to think outside their respective boxes....possibly to think once again like seven-year-olds.

Image Credit: Physical Review Letters, Volume 99, 213901 (2007)

Gone With the Wind

2010-04-01T16:11:00.005-04:00

“…for it is no more than a dream remembered. A Civilization gone with the wind.”
From the movie Gone With the Wind, 1939

Not just a civilization but an entire star is now gone with the wind. In this composite image, NASA’s Chandra and Spitzer space telescopes have beautifully captured the turbulent remains of a supernova explosion.

The white dot, near the center of the image, is the rapidly rotating neutron star, or “pulsar,” that was left behind when the dying star’s inner core collapsed. The collapse, in turn, created a violent shock wave that threw the star’s outer atmosphere outward. After many, many years, this fast-flowing river of dust and gas (seen in red) is now being heated and lit up by a nearby cluster of stars. The pulsar is adding to the mix by ejecting a wind of high-energy particles at high velocities (seen in blue).

The Envelope Please

2010-02-22T13:49:00.000-05:00

There's that old cliché that makes the rounds whenever award season arrives: "It's an honor to just be nominated," say the finalists with joyful assurance. Can they possibly mean it?

I just learned that I am a nominee for the Los Angeles Times Book Prize in the science and technology category for my latest work The Day We Found the Universe. I'm competing with Graham Farmelo for The Strangest Man: The Hidden Life of Paul Dirac, Mystic of the Atom; Bill Streever for Cold: Adventures in the Worlds’ Frozen Places; Richard Wrangham for Catching Fire: How Cooking Made Us Human; and Carol Kaesuk Yoon for Naming Nature: The Clash Between Instinct and Science.

So, now I have my answer. It is a pleasure to be grouped among such accomplished writers. The envelope will be opened on April 23. Maybe we can hope for a five-way tie.

Mystery Man Revealed

2010-02-03T18:00:00.002-05:00

Here's an answer to my blog entry of 7 January 2010. Thanks to John Grula, librarian for the Observatories of the Carnegie Institution of Washington, the mystery man in the cover photo of my latest book, The Day We Found the Universe, is now identified. (He is the white-haired gentleman standing behind Lick Observatory director William Campbell, who stiffly presides at the far right in the picture, hat perched precisely on his head. The others from left to right are Einstein, his assistant Walther Meyer, with Edwin Hubble right behind Meyer, and Mount Wilson director Walter Adams in the center.)

According to Grula, the man in question is Arthur S. King, a staff member at Mount Wilson from 1908 to 1943. He headed the observatory’s physics laboratory, where he specialized in divining the spectral lines of elements at various temperatures (important in discerning the chemistry of the heavens). He also showed how magnetic fields can affect the spectral line patterns, which helped scientists reveal the strength of magnetic fields in sunspots. He died in 1957 at the age of 81.

Grula even has a guess as to who “Mr. Forehead” is, the man seen peeking behind King. The “rimmed glasses,” “healthy shock of combed-back dark hair,” and “short stature,” according to Grula, suggest it might be Milton Humason, Hubble’s observing partner in surveying the expanding universe in the 1930s. The problem is that Humason is not seen in any other pictures taken that day, January 29, 1931, when Einstein visited the mountaintop. And in another picture of Humason and Hubble that I have seen, Humason is not that short; the top of his head comes up to about Hubble’s eye level. This man appears far smaller. So, one mystery remains.

Smash...Boom...Bang!

2010-02-02T11:25:00.003-05:00

Who knew the solar system had a traffic problem?

In January, a sky survey of near-Earth asteroids found something so unusual that astronomers quickly used the Hubble Space Telescope to inspect it more closely. What at first looked like a comet turned out to be the remnant of a spectacular cosmic collision: two asteroids recently smashing into one another. It's estimated the space rocks had been hurtling toward one another at around 3 miles per second (five times faster than a speeding bullet).

The result, seen in the Hubble photo above, is an unusual X-pattern near the nucleus of the object, with cometlike filaments of dust and gravel streaming back, due to radiation pressure from sunlight. At the time this picture was taken, this asteroid/comet was some 90 million miles from Earth. The nucleus that remains (the white dot at the left in the inset) is about 460 feet in diameter, longer than a football field.

P/2010 A2 (its official name) belongs to a sort of asteroid aristocracy. It orbits among a family of asteroids that originated from a collisional shattering more than 100 million years ago. One fragment of that ancient smashup may have struck Earth 65 million years ago, triggering a mass extinction that wiped out the dinosaurs.

The Stars Above Us, Govern Our Conditions

2010-01-29T12:26:00.004-05:00

The noted astrophysicist Geoffrey Burbidge (left) died on January 26. He was 84 and should have won the Nobel Prize.

Burbidge collaborated with his wife Margaret Burbidge, William Fowler, and Fred Hoyle on one of astronomy’s most celebrated journal articles. In fact, this seminal publication has attained such a transcendent stature that astronomers simply refer to it, like some chemical formula, as B²FH (pronounced B-squared FH), from the initials of the authors’ surnames. Within this formidable paper, published in the Reviews of Modern Physics in 1957, the four researchers elucidated a variety of routes for synthesizing the elements within stars. They helped prove that all the substantial elements that make up our body and the planets—the heavier elements such as carbon, oxygen, nitrogen, silicon, and so on—were first manufactured within a star. How the elements were constructed was a daunting problem at the time, and they brilliantly solved it. They taught us that we are truly composed of stardust. How appropriate, then, that their historic paper, more than one hundred pages in length, opened with a quotation from Shakespeare’s King Lear: “It is the stars, the stars above us, govern our conditions.”

Though Burbidge didn’t receive the Nobel (Fowler did in 1983 for his experimental work), he and his wife received many of astronomy’s highest honors, including the Gold Medal of Great Britain’s Royal Astronomical Society.

Only thirty-two years old at the time of his great accomplishment, Burbidge went on to cast a considerable shadow in the astronomical community. He directed the Kitt Peak National Observatory in Arizona for many years and was editor-in-chief of the Annual Review of Astronomy and Astrophysics for thirty years.

He was also one of astronomy’s most notable gadflies. Long after astronomers came to accept the Big Bang as the best description of the universe’s behavior, Burbidge continued to argue for a quasi-steady-state cosmology. He believed that quasars are not young and distant galaxies, despite their high redshifts, but rather new matter ejected from more nearby galaxies that are roiling with activity. He continued to press this point, right up to his last paper, which he published shortly before his death.

My last contact with Geoffrey was over the phone four years ago, when I interviewed him for a profile I was doing of Margaret for Smithsonian magazine. As always, he was both gracious and informative about the long collaboration with his wife. But he also didn’t miss the chance to convince me to do another story afterward—a story that would question the Big Bang and showcase his latest proof for doing so. I never got around to it.

All the King's Men

2010-01-07T16:45:00.002-05:00

I've had many inquiries about the cover of my latest book. It shows Einstein and company during a visit to the top of California's Mount Wilson on 29 January 1931. It was the one and only time Einstein made the trip. The group is standing in front of the dome of the observatory's historic 100-inch telescope, the instrument Edwin Hubble used to make his major discoveries.

Everyone wants to know, who are those other people? Here's the scoop (as far as I know it): The tall man right behind Einstein's hair and above the short guy in front of him is Hubble. The short guy is Walther Meyer, Einstein's assistant. The man in the hat, slightly leaning in the center, is astronomer Walter Adams, then head of the Mount Wilson Observatory. The stiff-looking man on the right with the distinguished chapeau is William Campbell, who at the time was directing Lick Observatory (Mount Wilson's competitor to the north). The other men, I believe, are professors from Caltech. (If anyone knows who they are, please contact me.) I feel sorry for the man in the very back who is viewed only as a forehead, a lost opportunity at being seen with the world's most famous scientist. What I love best is the old car in the background.

I was happy to learn recently that Vintage Books will be using the same cover for my paperback, coming out in March. I can't imagine any other depiction that captures the topic and the era so well.

Nightfall

2009-12-16T18:14:00.002-05:00

Perhaps it was due to Isaac Asimov. His famous short story "Nightfall" spoke of a world situated within a cluster of stars. Only once every two thousand years did the planet experience a true night, when darkness fell and the full splendor of the heavens became visible. This unfamiliar view so traumatizes everyone, that chaos ensues and civilization collapses.

Upon reading that tale as a child, I was captivated by the idea of living within a star cluster. No wonder I use, in the banner of this blog, the stunning image of NGC 3603, one of the most massive star clusters in the Milky Way galaxy. Located 20,000 light-years away, in the Carina spiral arm, it's a veritable jewel box of hot, blue-white stars. Our sun, by comparison, is a relative hermit out here in the galactic suburbs.

NGC 3603 is one of my favorite Hubble Telescope pictures, but it now has some competition. This past fall Hubble's Wide Field Camera imaged a new star cluster bursting into life within the Large Magellanic Cloud, a satellite of the Milky Way. Only a few million years old (mere days compared to the Earth's age), the sapphire-like stars―several over 100 times more massive than our Sun―are now blowing off their dusty cocoon and brilliantly shining.

Happy Winter Solstice!

The Earth As a Crescent Moon

2009-11-12T13:49:00.002-05:00

This spectacular image of our home planet was captured today by an instrument on the European Space Agency's Rosetta comet chaser as the spacecraft approached Earth for its third and final swingby. There's no place like home.

Superman's Eyes

2009-11-10T12:33:00.006-05:00

Imagine your eyes could register light across the electromagnetic spectrum—discerning not just visible rays but infrared and x-ray as well. That’s what NASA has done, releasing a composite image of the Milky Way’s turbulent center that combines three distinct views gleaned from its great observatories currently circling the Earth: the Hubble Space Telescope, the Chandra X-Ray Observatory, and the Spitzer Infrared Space Telescope. This was done to commemorate the four-hundredth anniversary of Galileo first turning his small telescope to the heavens in 1609. Galileo would be pleased.

What is seen in this stunning picture is the chaotic environment surrounding the galaxy’s core (marked in white, center-right), where a supermassive black hole nearly four million times more massive than our Sun resides. Permeating the region is a diffuse blue haze of x-ray light from gas that has been heated to millions of degrees. This is generated by outflows from the supermassive black hole, as well as by winds from massive stars and by stellar explosions in the region. The infrared light, depicted in red, reveals where newborn stars are just beginning to emerge from their dark and dusty cocoons. The yellow represents the Hubble telescope’s near-infrared observations, revealing hundreds of thousands of stars and glowing clouds of gas.

The width of the entire image covers about half a degree on the sky (in the direction of the constellation Sagittarius), about the same angular width as the full moon.

Visualizing Hubble

2009-10-07T17:28:00.010-04:00

I was just introduced today to an intriguing website called Many Eyes, run by IBM. You can check it out at http://manyeyes.alphaworks.ibm.com/manyeyes. Or just type "many eyes" into a search engine to get there.

One of the site's many features is giving you the ability to turn text into an image. I downloaded the preface to my latest book The Day We Found the Universe, for example, and chose to display it as a "wordle," which shows how frequently words appear in your text by the size of each word. You can even tweak these word "clouds" with different fonts, layouts, and color schemes. Here's how mine came out:

It's fascinating how well the central themes of my book just pop out, as if by magic. Edwin Hubble would certainly have liked the outcome.

Cosmic Matters

2009-09-21T10:31:00.007-04:00

A month ago astronomers announced that the amino acid glycine was detected in a comet. The discovery was made while analyzing samples brought back to Earth by the Stardust spacecraft, which flew through Comet Wild 2 in 2004.

My immediate reaction upon reading this news in the paper was, “How far we have come!” For most of history, astronomers could not be sure that the stuff of the heavens was the same as the stuff on Earth. And they figured an answer would be forever out of their reach. That is, until 150 years ago when Gustav Kirchhoff (left in picture), a professor of physics at the University of Heidelberg, and chemist Robert Bunsen (on the right), creator of the famous laboratory burner, showed us how to identify substances by the specific colors of light they emitted during chemical reactions or when burning. And since light knows no distance in space, electromagnetic waves can be effectively studied whether the light originates from a distance of one foot within a laboratory or from one million light-years away.

Kirchhoff eventually turned his attention to the heavens and with his spectroscope identified a number of elements in the Sun’s atmosphere, including sodium, iron, calcium, magnesium, chromium, barium, copper, zinc, and nickel. Here was definitive proof that the chemistry of the Earth was indeed identical to the chemistry of space. Within a few years, other astronomers reported finding similar elements in the stars. The long-standing Aristotelian belief that cosmic matters differed from the terrrestrial elements was finally abolished.

A century later, astronomers became even more ambitious. In 1955 physicist Charles Townes, who would go on to win a Nobel prize for his invention of the maser, gave a talk suggesting that celestial elements were likely linking up and forming actual molecules out in space. Among his candidates were carbon monoxide (CO, the stuff of car exhaust), ammonia (NH3), water (H2O), and the hydroxyl radical OH, the oxygen-hydrogen combination that distinguishes all alcohols. But most astronomers at the time were convinced that such molecules were quickly destroyed and hence too rare to seek out.

Fortunately a few MIT radio astronomers didn’t heed those warnings and looked anyway. In 1963 they found OH screaming out at 1,667 megahertz in the supernova remnant Cassiopeia A. A few years later, Townes himself, along with colleagues at the University of California at Berkeley, recorded the radio cries of ammonia and water from space. A race quickly ensued to snare the next new molecules. By 1973 nearly thirty cosmic molecules were identified; by the end of the 20th century, the total was more than a hundred—from ethyl alcohol and hydrogen cyanide to methane, formaldehyde, and nitrous oxide (or laughing gas).

And now the list includes an amino acid, one of the vital building blocks for life. The foundations for life on Earth may have been laid down before our planet even formed nearly five billion years ago.

Galaxies and Nebulae and Clusters, Oh My!

2009-09-10T11:27:00.016-04:00

After being rejuvenated from its space shuttle servicing mission last May, the 19-year-old Hubble Space Telescope is officially back in business. Engineers had spent the last three months focusing, testing, and calibrating. But now it’s back to photographing the universe like never before. Yesterday, NASA released the first stunning snapshots from the upgraded scope. They include a remarkable butterfly-shaped nebula (top left), a galaxy cluster as crowded as a subway in rush hour (bottom left), and a roiling stellar nursery (bottom right). Full details can be obtained by going to http://www.spacetelescope.org/news/html/heic0910.html.

As a nod to astronomer Edwin Hubble, I wish they had photographed NGC 2261 again as well, a comet-shaped cloud of gas located in the direction of the Monoceros constellation (left). While working on his doctoral thesis at Yerkes Observatory in Wisconsin around 1914, Hubble took a picture of this nebula and compared it with photographs taken earlier at other observatories. He noticed that his recent photo displayed distinct differences from previous ones, which proved that certain faint nebulae could change over time. It was his first major discovery. Today, this object, located within the Milky Way, is known as Hubble’s variable, a reflection nebula made of gas and fine dust fanning out from the star R Monocerotis. It's about one light-year across and lies about 2,500 light-years away.

NGC 2261 always held a fond place in Hubble’s heart. Soon after he arrived at the Mount Wilson Observatory as a staff astronomer in 1919, he got his first crack at the newly opened 100-inch telescope, what he called his “magic mirror.” It was on Christmas Eve, and he couldn’t have asked for a more fitting holiday present. The atmosphere was almost at its best, and it was also dark-sky time, the Moon having just set in the west. His best photograph of the night came when he aimed the giant scope at his variable nebula. From that point on, it became his observational “mascot.”

Later in his observing life, 1949, Hubble had the honor of being the first scheduled observer on the giant 200-inch Hale Telescope situated on California’s Palomar mountain. Needless to say, he got started by imaging his good luck charm, NGC 2261. Perhaps, Hubble Space Telescope astronomers should consider adopting this intriguing nebula as their mascot, too. Who knows, the luck might rub off. (Though from the look of these photos, maybe they don't need it.)

Two, Four, Six, Eight, Who Do We Appreciate

2009-08-25T16:10:00.005-04:00

An interesting event happened last May, but I only recently learned of it, thanks to Michael Long, a trustee of the Mount Wilson Institute. When the space shuttle Atlantis went into space last May to repair the Hubble Space Telescope, it took along a very special memento: a century-old basketball that Edwin Hubble used in 1909 while a star player for the University of Chicago. Hubble and his fellow Maroons scored a winning 18-12 victory over Indiana University with the ball. Astronaut John Grunsfeld, also a Chicago alumnus (a PhD in 1988) made the arrangements to take it on the flight with him. On his two previous space telescope missions, Grunsfeld flew with the eyepiece of a telescope that Hubble had peered through at Yerkes Observatory in Wisconsin and the cover of Hubble's doctoral dissertation.

Hubble, Class of 1910, had been awarded a scholarship to attend the university partly due to his superb athletic skills. He participated in track (though seldom winning) but did far better in basketball, as his exceptional height for the day, six feet two inches, gave him an advantage playing center. He and his teammates were national champions in 1909. They swept through the Big Ten season and won the national title by defeating the University of Pennsylvania in two games.

Above image: Hubble's winning 1909 basketball aboard the space shuttle Atlantis last May (John Grunsfeld)

My Regards to the Squashes

2009-08-18T10:45:00.009-04:00

When I give talks about my latest book, The Day We Found the Universe, I'm often asked, "What is your favorite story from the book?" The answer is easy for me: the squashes.

While doing research for the book two years ago at the Lowell Observatory in Flagstaff, Arizona, I eagerly read all the correspondence between Percival Lowell, the observatory's Boston Brahmin founder, and his top assistant Vesto Slipher (the astronomer who would later be the first to discover galaxies moving outward). Lowell, often traveling on business during the early 1900s, remained in close contact with Slipher about all kinds of matters. From afar, Lowell offered his advice on matters astronomical (“Don’t observe sun much. It hurts lenses.”), administrative (“Permit nobody whatever in observatory office…”), and personal (“Will you kindly see if shredded wheat biscuit are to be got at Haychaff.”).

But I laughed out loud in the library (fortunately, only I and the archivist Antoinette Beiser were there at the time) when I came across a wonderful series of letters regarding the observatory's garden. I told Antoinette then and there that I was determined to include the story in my book. Here's how it turned out:

Lowell doted on his observatory garden and insisted on news of its condition whenever he was away. “How fare the squashes?” asked Lowell one year as fall harvest approached. His letter the following week closed with, “My regards to the squashes.” And finally, “You may when the squashes ripen send me one by express.”

Slipher did not respond. “Why haven’t I received squashes. Express at once if possible,” Lowell anxiously telegraphed right after Christmas. Slipher reluctantly had to answer that the poor gourds, alas, had shriveled up and died.

All was forgiven, though, by next spring [1902]. “Thank you for taking so much pains with the garden! Just keep on planting and you will get something,” wrote Lowell. Slipher did; by July he was sending Lowell his latest bounty. “Your vegetables came all right and delighted me hugely,” replied Lowell. More were sent in October.

As with his gardening, Slipher made progress on the spectrograph as well, eventually becoming a virtuoso at its operation....

Above images: (top) Percival Lowell and (bottom) Vesto Slipher (Lowell Observatory Archives)

Hi-Ho, Hubble, Away!

2009-08-09T15:21:00.007-04:00

After being interviewed recently on a national radio program, I was surprised and thrilled to be contacted by a not-so-distant relative of Edwin Hubble.

Vickie Kalthoff of Chesterfield, Missouri, e-mailed that her grandfather, Ralph James, and Hubble’s mother Virginia were first cousins (both distant relations to the famous outlaw Jesse James). In fact, Vickie's brother was born in the same house that Hubble was born in Marshfield, Missouri, a town that celebrates its most famous resident with a replica of the Hubble Space Telescope on the courthouse grounds. She recalls the superb nighttime sky there in the 1940s and 1950s: “I would stand outside at night, and I felt as if I were floating in the Milky Way.”

Vickie’s grandfather once drove from Kansas to California just to meet the great astronomer, and she wondered what Hubble thought about her “cowboy” gramps. I thought about that, too. While a Rhodes scholar at Oxford University in his youth, Hubble completely reinvented himself. He adopted a British accent that he maintained the rest of his life, dressed like a dandy, and could often be arrogant and standoffish to his fellow astronomers. He married into a rich Los Angeles family and throughout his life seemed intent on erasing his Midwestern roots.

In fact, Hubble rarely saw his mother and siblings, who remained in the Midwest. But Vickie told of one particular visit. Her mother and aunts were present when Hubble returned to the family ranch and got on a horse backwards. “They never forgot that,” says Vickie, “but I am sure he was teasing them.”

Above image: Replica of the Hubble Space Telescope on the courthouse grounds of Marshfield, Missouri. (Credit: freepages.genealogy.rootsweb.ancestry.com)

You're Not the Center of the Universe, You Know

2009-07-19T08:00:00.005-04:00

My Op-Ed published in the Washington Post, July 19, 2009

Walk into an open field on a clear, moonless night. Overhead, sparkling stars sprinkle the sky. All of them seem equidistant from you―and no one else―and you are lulled into imagining yourself at the center of the universe.

For nearly 500 years, astronomers have struggled to break that illusion. Our petty standing in the cosmos is a scientific fact, if not a visceral experience. Earth zips at nearly 67,000 miles an hour around the sun, which in turn completes one lap around the Milky Way every 220 million years, meaning that the last time we were in this neck of the galaxy, dinosaurs were getting ready to rule the planet. Still, as you look skyward in that pitch-black field, Earth seems to be at the heart of all creation.

We could blame Aristotle. So authoritative was his pronouncement of an Earth-centered universe in the 4th century B.C. that few challenged the idea for nearly two millennia. Over time, the urge to better explain the universe's behavior gave rise to new models. In 1543, Nicolaus Copernicus boldly placed the sun at the center of the universe, shoving the Earth into motion. The radiant sun was at last in its proper perch, "as if resting on a kingly throne," he wrote.

Copernicus was not disturbed at all by a moving Earth but was troubled by a rotating sky. The Polish mathematician and astronomer, though, knew quite well the consequences of challenging conventional notions. In the preface to his great work, "On the Revolutions of the Heavenly Spheres," he predicted that "as soon as certain people learn that in these books of mine . . . I attribute certain motions to the terrestrial globe, they will immediately shout to have me and my opinion hooted off the stage."

That fate fell upon Galileo, who starting in 1609 gathered the crucial evidence supporting Copernicus's heliocentric vision. In 1633 he was brought before the Inquisition and eventually put under house arrest for daring to oppose an Earth relaxing at the universe's center.

By the time of Newton, decades later, such hostility had faded. For one, Sir Isaac's physics could at last explain why we aren't thrown off the planet as the Earth rotates and orbits the sun. But even though Copernicus moved Earth from the hub of the solar system, its inhabitants remained confident that they retained a privileged place at the center of the Milky Way, the sole galaxy. Homo sapiens is an egotistical species; we resist being kicked out of a prime spot in the cosmic scheme of things.

That confidence, though, withered as astronomy underwent a spectacular transformation starting in the 19th century, an era teeming with technological innovation. Prominent industrialists, enriched by the Gilded Age, provided the money that allowed dreamers to construct the powerful telescopes they had long desired.

With one of those new instruments atop California's Mount Wilson, Harlow Shapley resized the Milky Way. He discovered in 1918 that it was 10 times larger than previously thought and, along the way, he relocated the sun and its planets into the galaxy's suburbs. The sun resides roughly 30,000 light-years from the galactic center, more than halfway to the Milky Way's edge. "The solar system is off center, and consequently, man is too," Shapley liked to say.

But Shapley did not take the next step; he, too, fell victim to cosmic pride. Despite the growing evidence that the Milky Way was not alone in the universe, he held fast to his beloved Big Galaxy model: Our galaxy remained at center stage. We lived in a solitary, star-filled oasis suspended in a darkness of unknown depth.

Shapley's vision was demolished in 1924, when Edwin Hubble proved that the cosmos is populated with myriad galaxies as far as the telescopic eye can see. The Milky Way suddenly became a bit player in a much larger drama.

The history of astronomy is a continuing extension of the Copernican principle, moving us farther and farther from the front row. It's a principle of irrelevance that involves not only our position in space and time but also the contents of the universe. In recent decades, astronomers have learned that a hidden ocean of cosmic matter―comprising about 85 percent of the universe's mass―surrounds us, possibly elementary particles yet to be discovered. The stuff of stars, planets and us is but the flotsam in this enveloping sea.

More startling―and taking the Copernican principle to its finale―our universe may not be the only one. As physicists attempt to construct a theory that unifies all the forces of nature, one theme repeatedly arises: that additional cosmic realms may be lurking in other dimensions. We could be part of the multiverse; the Big Bang might have occurred when universes outside our dimensional borders bumped into one another.

The main response to this astounding theory has been to bury our heads in terra firma. Yet such a wider perspective offers some succor, allowing our earthly concerns to shed away. Hubble knew this. During a visit to the astronomer's home, the English poet Edith Sitwell was shown slides depicting the many galaxies that cannot be seen with the naked eye. "How terrifying!" she exclaimed. To which Hubble replied: "Only at first―when you are not used to them. Afterwards, they give one comfort. For then you know that there is nothing to worry about―nothing at all."

Granted, the hugeness of the cosmos is difficult to perceive and, as Sitwell expressed, horrifying to ponder. A character in Thomas Hardy's 19th century novel "Two on a Tower" gives splendid voice to this apprehension: "There is a size at which dignity begins; further on there is a size at which grandeur begins; . . . further on, a size at which ghastliness begins," says astronomer Swithin St. Cleeve. "That size faintly approaches the size of the stellar universe."

Indeed, our cosmic address is getting excruciatingly long: Planet No. 3, Solar System, Orion Spur on the Sagittarius Spiral Arm, Milky Way, Local Cluster, Virgo Supercluster, Universe, Multiverse.

It's time for earthlings to acknowledge our minor-league status and collectively grasp the magnificent vastness that engulfs us all. While a widespread recognition of Earth's humble station is unlikely to end conflict here, fully comprehending our planet's infinitesimal place in the universe might be a modest step toward diminishing our hubris. Earth is but a speck, the cosmic equivalent of a subatomic particle hovering within an immensity spanning billions of light-years.

And we can still savor our cleverness in figuring this out.

Image Credits: (top) Sagittarius Star Cloud (Hubble Heritage); (lower) Imagined Multiverse (Nature)

Shedding a Tear for 40th Anniversary of Moon Landing

2009-07-13T11:26:00.009-04:00

My father often liked to tell this story. In 1930, when he was eight years old, he saw an advertisement in a magazine depicting a series of yearly calendars going off into the distance. The very last calendar was 1960, a time to him so distant he couldn't imagine ever getting there.

I had my own "calendar moment" in 1968. Instead of a magazine ad, it was a movie. Sitting in the darkened theater, seeing the opening credits for 2001: A Space Odyssey come onto the screen, I couldn't quite comprehend that I would someday enter the 21st century. It seemed a fantasy. But when and if I did make it to the next millennium, it would surely be populated with videophones, space station hotels, and PanAm space stewardesses. I soon had proof we were on our way. Within a year, on July 20, 1969, two men landed on the Moon and CBS anchorman Walter Cronkite wiped away a tear when they did.

2001 has now come and gone. We have videophones and a far less luxurious space station, but no longer any presence on the Moon. The last astronauts to journey across the dusty soil did so in 1972, nearly four decades ago. Who knew that Cronkite's tear of joy would turn into a tear of disappointment for those of us who longed for the life of 2001 to come true.

Image Credits: (top) Walter Cronkite (CBS News); (bottom) Space Station Hilton Hotel (from 2001: A Space Odyssey)

Goldilocks and the Black Hole

2009-07-01T13:06:00.005-04:00

It’s like Goldilocks and her three bears. For decades, astronomers have identified either supermassive black holes, each a huge entity containing the mass of millions to billions of Suns and sitting smack dab in the heart of a galaxy, or far smaller ones weighing anywhere from three to twenty solar masses. But now astronomers in France, using the European Space Agency’s XMM-Newton X-Ray Space Telescope, have spotted a black hole that’s more toward the middle. Goldilocks might even say it’s “just right.” In a galaxy far, far away—some 290 million light-years from Earth—the observers detected the unique x-ray signature of a medium-sized hole that contains more than 500 times the mass of our Sun. Labeled HLX-1, this source offers the best evidence yet for what theorists have long suspected: that black holes come in a wide range of sizes, not just extra large or petite.

The first hint that black holes might exist in the real universe arrived in 1939 when J. Robert Oppenheimer (who later headed the Manhattan Project that constructed the first atomic bomb) and his student Hartland Snyder published a paper showing that if a dying star had enough mass it could gravitationally collapse in a wink and be crushed to a singular point. The result: space-time gets so warped around this collapsed star that it literally closes itself off from the rest of the universe. “Only its gravitational field persists,” reported Oppenheimer and Snyder.

But astronomers at the time weren’t ready to believe that such bizarre objects could possibly inhabit, what seemed at the time, their calm and serene universe. Even Einstein wrote a paper attempting to prove that they were impossible to form.

We have the late Princeton physicist John Archibald Wheeler to thank for reinvigorating this line of research back in the 1960s, while all others ignored it. Confident at first that some kind of force would surely step in to halt this horrific stellar contraction, Wheeler saw in his equations that nothing—absolutely nothing—could prevent the collapse. The plummet into the abyss was inevitable.

Wheeler went on the lecture circuit to discuss his theoretical findings, aided by the discovery of pulsars, not yet understood in 1967 to be spinning neutron stars but surely proving that strange celestial objects lurk in the dark envelope of space. Wheeler at the time lectured that astronomers should consider the possibility that the pulsars were “gravitationally collapsed objects,” as he then awkwardly called them. “Well, after I used that phrase four or five times, somebody in the audience said, ‘Why don’t you call it a black hole?’ So I adopted that,” Wheeler told me as I was researching my book Einstein’s Unfinished Symphony. Some of Wheeler's associates, though, suspect he carefully crafted the term himself after years of thought. Whatever the origin, the name became official and went into the scientific lexicon. Nature’s weirdest object, resisted by astronomers for so many decades, is now taken for granted. And, as witnessed by the latest data from the XXM-Newton space telescope, the evidence for the existence of black holes is piling up daily.

Above images: (1) Artist's impression of the new source HLX-1 (represented by the light blue object to the top left of the galactic bulge) in the periphery of the edge-on spiral galaxy ESO 243-49 (Credit: Heidi Sagerud); (2) John Wheeler in 1967, at the time he coined the term "black hole." (New York Times)

Galileo for a Day

2009-06-16T13:53:00.006-04:00

It looks rather mundane, like an extra-long paper-towel tube: a blotchy brown cylinder about three feet long and two inches wide made out of wood and varnished paper, all held together by rings of metal wire. Now on display at the Franklin Institute in Philadelphia, this object is, in reality, a telescope made by Galileo, one of only two still in existence.

I was fortunate to be at the Institute last week, scheduled to give an evening lecture. Arriving early, I had time to peruse the Galileo exhibition and to my delight found the rooms, filled with astronomical artifacts from the Renaissance, deserted. Walking by the astrolabes, compasses, and quadrants, I turned a corner, and there it was: Galileo’s telescope, perched at an angle on two transparent rods. It was enclosed in a tall glass case, standing solitary and majestic on the polished wooden floor. I was alone with one of the greatest artifacts in astronomical history.

Despite the instrument's plain appearance, it took my breath away. No one is sure what discoveries Galileo made with this specific telescope (he constructed many), but the aura of fame still surrounds it. I was able to kneel down to position my eye within an inch of the eyepiece, separated only by the glass case. Peering down the tube, which holds Galileo’s original lenses, I saw a blurry white spot. Alas, just the museum ceiling. But in my imagination, I was sighting the phases of Venus, mountains on the Moon, and Jupiter’s satellites for the very first time, just as Galileo did four hundred years ago.

Above image: White-gloved representatives of Instituto e Museo Nazionale di Storia della Scienza in Florence, Italy, place the Galileo telescope into its glass display case at the Franklin Institute in Philadelphia, Pennsylvania. (Reuters)

The Oprahs of the 16th and 17th Centuries

2009-06-08T16:17:00.013-04:00

Admit it. You experienced it, too, during your introductory astronomy course in college. You gritted your teeth through the early-semester lectures on those long-haired astronomers of old. Who wanted to hear about ancient astronomy when more exciting and modern events—black hole formation, colliding galaxies, and the Big Bang—awaited you in weeks to come.

But there’s plenty to keep students both informed and entertained as instructors build that historic foundation, so necessary to understanding current celestial matters. It can be found in the original sources. Back in the 16th century, scientific communication was far more relaxed—it could be quite humorous at times and often confessional. Take Nicolaus Copernicus, for example, the administrative canon who boldly placed the Sun at the center of the solar system (and hence the universe). In doing this, he also put Earth into motion.

But how did Copernicus open his famous work, On the Revolutions of the Heavenly Spheres? Actually, in a way that would make Oprah proud: “I can reckon easily enough…,” he wrote in 1543, “that as soon as certain people learn that in these books of mine which I have written about the revolutions of the spheres of the world I attribute certain motions to the terrestrial globe, they will immediately shout to have me and my opinion hooted off the stage….The scorn which I had to fear on account of the newness and absurdity of my opinion almost drove me to abandon a work already undertaken.”

You don’t see such candor in the Astrophysical Journal these days. It’s downright refreshing.

Then there’s Johannes Kepler, whose portrait looks like Santa Claus in his youth. Like others, I thought of Kepler as one of those “dead white men” of astronomy. He was the one who proved that planetary orbits are ellipses, not circles, which was crucial to Isaac Newton’s establishing in 1687 his revolutionary theory of gravity. But all the fun is in how Kepler explained his proof in a book titled Astronomia nova, the most unusual (and frank) account of a discovery I've ever seen. With seventy chapters dense with charts, computations, and diagrams, it was written as the noted German mathematician progressed through his tortuous calculations concerning the orbit of Mars. His dead ends and blind alleys are included side by side with his successes.

Chapter by chapter he plugs numbers into his models and with a seasoned wit shares his gripes with the reader. “If this wearisome method has filled you with loathing,” he writes in Chapter 16, “it should more properly fill you with compassion for me, as I have gone through it at least seventy times….” He’s still moving through his myriad computations into Chapter 50: “How small a heap of grain we have gathered from this threshing! But you also see what a huge cloud of husks there is now.”

The struggle became his personal “war with Mars,” his enemy. “And now," he wrote, "there is not much to prevent the fugitive enemy’s joining forces with his fellow rebels and reducing me to desperation, unless I send new reinforcements of physical reasoning in a hurry to the scattered troops and old stragglers….”

Kepler at last won his battle with Mars in 1609, exactly four hundred years ago. For more information on these episodes, I recommend perusing my book Archives of the Universe: 100 Discoveries That Transformed Our Understanding of the Cosmos.

Above photos, from top to bottom: (1) Copernicus with his heliocentric model of the universe and (2) Kepler, a portrait done around 1610 when he was 39.

It Should Have Been 2010

2009-06-02T11:51:00.018-04:00

For astronomy aficionados, it’s old news: 2009 is the International Year of Astronomy. But in case you haven’t heard, this celebration is now occurring in honor of Galileo, who four hundred years ago first peered at the heavens with his homemade “optical tube.” (The word telescope wasn’t coined until 1611.)

I wish astronomy officials had waited until 2010, in order to commemorate Galileo’s famous book Sidereus nuncius (“The Sidereal Messenger” or “The Starry Messenger”), a compilation of the notes and letters he wrote during his first months of observation. Others were beginning to look at the nighttime sky with spyglasses (for one, Thomas Harriot in England), but Galileo was the first to publish, providing a keen analysis of his observations. It was Sidereus nuncius, a best seller in the spring of 1610, that made Galileo famous. That’s when the professor, then 46 years old, became the A-list celebrity of his time. The public was mesmerized by his reports of craggy mountains on the Moon, a Milky Way composed of myriad stars, and moons circling the planet Jupiter—all previously unknown. 2010 seems a more fitting time for a year-long salute to astronomy. It also wouldn’t have competed with the “Year of Darwin,” also now going on to mark the 150th anniversary of Darwin’s On the Origin of Species.

But who am I, a humble science writer, to challenge the all-powerful Oz. . .er, International Astronomy Union. So, I’m doing my bit for the cause. Natural History magazine will be excerpting a few sections from my latest book, The Day We Found the Universe, over the course of the year as a way of joining the celebration and recognizing, as the editors put it, “the events and scientists that have advanced our understanding of the cosmos during the last hundred years.” The first article, a selection from my book’s preface, is now out in the magazine’s June issue.

Above photo: Five pages from Sidereus nuncius, including Galileo's drawings of the Moon.

Fasten Your Seat Belt

2009-06-01T11:02:00.009-04:00

I envy actors. They get their reviews in one, fell swoop—both good and bad. For authors, it’s a slow, agonizing process that begins even before their latest work is out on the bookshelves. First come the pre-reviews in the publishing industry press, such as Publishers Weekly, Kirkus Reviews, and Booklist, which give bookstore owners and librarians a heads-up on the upcoming winners—and clunkers—coming their way. It lets them know what to order….and what to avoid. For authors, it’s like an out-of-town try-out: a forecast of their new “baby’s” reception.

I was fortunate. My latest book, The Day We Found the Universe, survived this first round. Every one of these early reviews was positive, with nary a disapproving comment. I even garnered the cherished “starred review” from Publishers Weekly, the industry’s equivalent of two thumbs up or the Good Housekeeping Seal of Approval. I was luxuriating in adjective heaven; the reviewers used such words as “vivid,” “remarkable,” “lively,” and “dynamic” to describe my prose. This can be dangerous, making you forget to fasten your seat belt for the unexpected “bumps” in the newspaper and magazine reviews to come.

For me, that wallop arrived on Sunday, April 26, in the Sunday Washington Post. It started off swell. Post reporter Joel Achenbach said right up front that “Bartusiak’s intelligent and engaging book may well become the standard popular account” about the birth of modern cosmology. I couldn’t have asked for a better blurb. But then came the dreaded on-the-other-hand: he despaired at the comprehensiveness of my tale, “at the arrival on the scene of yet another astronomer, yet another telescope, yet another set of photographic plates.” To me, it was like saying that Civil War book would be terrific if it weren’t for the arrival of yet another damn battle. But then I recovered when he wrote that my book is ultimately “about how hard science is, how taxing, particularly when you are trying to excavate truth from a grudging universe”—a beautiful way of rendering exactly what I intended in writing this book. Thanks, Joel.

From then on, it was clear sailing. Seed magazine said I offered my “trademark mix of meticulous research and vibrant prose”; New Scientist called the book “highly readable”; and Science News noted its “moments of drama and intimacy.” Oddly, several reviewers went out of their way to use the word “accessible” to describe my book, which makes me believe that many people readily assume that a science-themed book is going to be tough going. As a professor of science writing, I long for the day when that notion will no longer be automatic and work hard in helping my students make that happen.

My latest glee arose with Ben Cosgrove’s review in the San Francisco Chronicle on Sunday, May 17. He called my book “a small wonder” and described me as “a science writer of rare gifts.” Whew! My head is swelling as I type this. Time to fasten on that seat belt once again for the inevitable bump to come.

Click here to see excerpts from all the reviews of The Day We Found the Universe.

Above photo: Man Reading a Newspaper by Oskar Hoffmann, 1902 (Art Museum of Estonia)

Hubble Redux

2009-05-30T12:59:00.030-04:00

History can often be lazy. Not historians. They go after details with a vengeance. But over time we tend to remember historic tales in easy bites. Take Edwin Hubble, for example, namesake of the popular space telescope newly refurbished by the space shuttle astronauts. It's often related that Hubble went to the world's largest and best-equipped telescope in 1923—the 100-inch reflector atop Mount Wilson in California—and, voila, revealed a cosmos populated with myriad galaxies spread over space as far as the young astronomer could peer. But that is not the case at all.

In reality, Hubble's discoveries did not arrive in one eureka moment, but only after years of contentious debates over conjectures and measurements that were fiercely disputed. That was one reason for my interest in delving more deeply into this story, a rich saga published in my latest book The Day We Found the Universe. It shows how the avenue of science is more often filled with twists, turns, and detours than unobstructed straightaways.

Here are some surprises to be found within the book's pages:

Hubble didn’t really discover the expanding universe: The first person to observe that galaxies were racing away from us was Vesto Slipher at the Lowell Observatory in Arizona, an astronomer now largely forgotten. He first noticed the effect in 1913, sixteen years before Hubble’s historic observations. Slipher didn’t know at the time it was due to a universe expanding, but he did suggest the galaxies might be “scattering” in some way.
Hubble was a scientific cad: In 1929 Hubble pegged how the galaxies move outward but failed to note in his famous paper that half his data—the velocities—were Vesto Slipher’s measurements. There was no citation, no acknowledgment—a serious breach of scientific protocol. Slipher deserves half the credit. Privately, Slipher was bitter but too humble and reserved to demand his share of the glory.
The so-called “discoverer” of the expanding universe never liked the idea: For the rest of his life, Hubble had serious doubts about a universe expanding. He told a Los Angeles Times reporter, “It is difficult to believe that the velocities are real—that all matter is actually scattering away from our region of space.” In his scientific papers, he always referred to the galaxies’ “apparent” velocities, worried that a new law of physics might sneak in and change the interpretation.
A woman made the discovery of the modern universe possible: Henrietta Leavitt, working at the Harvard College Observatory, came upon astronomy’s celestial Rosetta Stone in 1912, which allowed Edwin Hubble twelve years later to prove that the Milky Way was not alone but just one of a multitude of galaxies. She found a new cosmic yardstick, based on blinking stars called Cepheid variables, to determine distances to far-off celestial objects, a task that was formerly impossible to carry out. She might have earned a Nobel prize for this work, if she had not died of stomach cancer at the age of 53.
Edwin Hubble was not much liked by his colleagues: Hubble, often arrogant and standoffish, rarely hung out with his fellow astronomers. One called him a “stuffed shirt.” Hubble preferred to socialize with the actors and writers in nearby Hollywood, the aristocrats of southern California. While a Rhodes scholar at Oxford University, he completely reinvented himself: he adopted a British accent that he maintained for the rest of his life, dressed like a dandy, and began to add dubious credentials to his résumé (like saying he once practiced law, which he never did). Hubble’s affectation for wearing jodhpurs, leather puttees, and a beret while observing, or going around and saying “Bah Jove,” was simply too much for the other astronomers to bear.
Not Hubble, not Einstein, but a Belgian priest first discovered how the cosmos truly operates: Both a theorist and a Jesuit priest, Georges Lemaître predicted in 1927—two years before Hubble measured it—that space-time was moving outward, with the galaxies going along for the ride. Here was the reason for Slipher's fleeing galaxies. Lemaître even estimated a rate of expansion close to the one that Hubble would later calculate. Since the young priest published this astonishing news in an obscure journal, no one noticed—no one at all.
The Hubble Space Telescope could have had another name: Three men had a good chance at proving the universe was filled with other galaxies, beyond the borders of the Milky Way, years before Hubble. Each had the opportunity and the expertise. But James Keeler at the Lick Observatory prematurely died in 1900 at the age of 42; Heber Curtis, also at Lick, took a promotion, taking himself out of the race; and Harvard astronomer Harlow Shapley was mulishly wedded to a flawed vision of the cosmos, a blunder he regretted for the rest of his life.

Above photos, from top to bottom: (1) Edwin Hubble; (2) Vesto Slipher; (3) Henrietta Leavitt; (4) Georges Lemaître

As For the Blog's Name.....

2009-05-28T17:12:00.031-04:00

In 1915 Einstein's general theory of relativity introduced the momentous idea that space and time are woven into a distinct object, whose shape and movement is determined by the matter within it. This grand theory anticipated the universe's expansion and turned its study into both an intellectual and observational adventure.

Centuries before this, early globetrotters had crossed the oceans in search of terra firma―solid land, new continents―previously unknown to them and ready for exploration. With his relativistic vision of space-time as a pliable fabric that can bend and stretch, Einstein allowed astronomers to recast the ancient terrestrial search into a far larger quest for cosmos firma. Glued together by the genius physicist, space and time have become cosmic real estate to be appraised, mapped, and scrutinized.

I now embark on my arm-chair explorations of this always-thrilling celestial landscape and hope to provide insights on astronomical discoveries, past and present, based on my thirty years covering the fields of astronomy and astrophysics both in books and for a variety of national publications, such as Discover, National Geographic, Smithsonian, Astronomy, and Sky & Telescope.

Above photo: Einstein, with inveterate pipe-smoker Edwin Hubble, on 29 January 1931 at the eyepiece of the 100-inch telescope on Mount Wilson in southern California. (Caltech Archives)