Leave a Good-Looking Corpse
That's what this is: the husk of a largely burned-out star, as photographed by the Spitzer Space Telescope (the Hubble's infrared-sensitive younger brother). Called the Helix Nebula, it lies about 700 light-years from space, and it's what our own solar system could look like in 5 billion years or so. What happens is that an aging Sun-like star blows off its outer layers in a kind of death rattle, creating an expanding cloud of gas. At the core is a white dwarf star--kind of a fiercely glowing leftover ember, still hot enough to heat the cloud and make it glow gorgeously.
The scientific importance here, largely overshadowed by the beauty of the image, is the reddish glow surrounding the white dwarf. It comes from dust, which would ordinarily have been blown away with the billowing gas cloud. This dust, though, was made after the blowoff: it comes from comets that survived that final gasp. Their orbits were disrupted enough during that even that they began crashing together, smashing each other to smithereens.
One historical note: the idea for the Hubble telescope originated with the late Princeton astronomer Lyman Spitzer, way back in 1947. When if was finally built, NASA named it, not after him, but after Edwin Hubble, who discovered the expanding universe in the 1920s. It wasn't until a new, infrared telescope went up in 2003 that Spitzer got the recognition he deserved.
One personal note: Spitzer was an avid mountaineer as well as an astrophysicist. He was officially reprimanded by the dean of Princeton's faculty for scaling the outside of Cleveland Tower, at Princeton's graduate college.
— M.L.
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