August 29, 2006: Cassiopeia A supernova by Hubble

[Undertoad]

It's been a while since we had a space shot. I imagine this will be tomorrow's Astro Pic of the Day; today, WaPo highlighted it and so I went and found a big version at Hubble's website. The image is actually a stitch of 18 different images, and I cropped it for our purposes.

Cassiopeia-A is the "youngest known remnant from a supernova explosion in the Milky Way." It's in the Cassiopeia constellation.

300 years ago, it was a massive star, sitting around 10,000 light years from us; then, one day, it just exploded. Nobody knows why; supernovae are pretty mysterious. Perhaps it found an empty ice cube tray in the freezer.

Cassie A. would have been much larger and more dense than our own sun, and the resulting explosion would have been so unimaginably massive as to be beyond our comprehension. All we see now is the result: a huge, expanding cloud of interstellar dust. If you're interstellarly allergic, you might want to avoid that section of the galaxy.

They actually don't know why nobody noticed the explosion 300 years ago. People were looking, by then, and writing down what they saw.

And 25 years ago, telescopy was less advanced and someone theorized that the center might contain a black hole. Now they say it doesn't. I dunno what it would look like here... shrug, big black hole I guess.

Wikipedia entry