About 700 light years away sits the expanding death cry of a star: the Helix Nebula, a four-light-year wide gas cloud blasted out when a star that was once like the Sun gave up its life.
A new image of it in colors just outside what the human eye can see shows just how much it does look like a screaming star:
[Click to ennebulenate, or download the huge 6600 x 600 pixel 35 Mb version.]
This image is in the near-infrared, taken using the European Southern Observatory’s Visible and Infrared Survey Telescope for Astronomy (VISTA), a 4.1 meter telescope in Chile. Equipped with a whopping 67 megapixel camera it can take pictures of large areas of the sky. The Helix nebula fits that bill: it's close enough to us that it's nearly the size of the full Moon in the sky.
This image is pretty nifty. It accentuates cooler gas than what we see in visible light. What's colored red in the picture is actually infrared light coming from molecular hydrogen, and shows the sharp ring-like edge of the nebula. What you're seeing here is not so much a ring as it is the walls of a barrel-like structure, and we happen to be seeing it nearly right down the tube (see Related posts below for all the info you could want on this amazing object).
It also accentuates the long, long streamers pointing directly away from the center. Those are comet-like tails coming from denser clumps of material boiling away as the fierce ultraviolet light of the central star floods out, their material flowing radially outward. This is seen in other nebulae as well.
And while it's beautiful and scientifically very useful (I would've killed for data this nice when I was researching these nebulae in grad school), it's also something of an existential reminder: someday, our own Sun will look a bit like this. Probably not quite this bright and well-defined; our local star doesn't quite have the power needed to light up its surroundings this way. But for all intent and purpose, you're seeing a snapshot of our solar system in seven or eight billion years.
Just in case you needed a little perspective this morning.
Image credit: ESO/VISTA/J. Emerson. Acknowledgment: Cambridge Astronomical Survey Unit