Superman's Eyes

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.