All in all, these three astronomers proved the existence of the "Kuiper belt," a disk of icy planetesimals long proposed to lie beyond the outer planets of our solar system. Their discoveries ultimately caused Pluto to be demoted to "dwarf planet," joining its more similar companions in the belt.
I was particularly thrilled for Jane, who I profiled in 1996 for Astronomy magazine. Click here to read how Jane's life journey took her from war-ravaged Vietnam to the outer reaches of our solar system.
Image Credit: MIT Lincoln Laboratory