Fireworks and pinwheels

Fireworks and pinwheels

Fireworks and pinwheels

Bad Astronomy
The entire universe in blog form
Feb. 8 2006 2:08 PM

Fireworks and pinwheels



Phil Plait Phil Plait




That's important, actually. There's some real science behind this pretty face! About three years ago, the light from an exploding star in that galaxy reached our telescopes here on Earth. It was designated SN2002fk, meaning it's a supernova, it blew up in 2002, and it was the 162nd one to be seen that year -- they are labeled alphabetically, so the first was 2002a, the second 2002b, the 27th 2002aa, etc. But more than that, it's a special type of supernova... the kind many astronomers like best.



Well, it's not that easy, of course. We haven't studied enough Type Ias to get a really good calibration on them. So when one appears in a nearby galaxy, like, say, NGC 1309, astronomers pounce on it. It's bright, so they can get good data on it, and dissect it as much as possible.

Why? Well, the explosions are so bright they can be seen from large distances, even billions of light years. If you see one blow up, and you can figure out its distance, you can use them to measure things like how fast the Universe is expanding (it's a bit like measuring distant car headlights at night to better understand the road you're on). In fact, these are the very kind of supernovae used to figure out the universal expansion is accelerating! Astronomers are very keen to understand this better; it's not exaggerating to say it's one of the biggest problems in cosmology right now.

So when you look at that picture and admire its sheer beauty, let the thought rumble around in your mind that one of those tiny dots in the image is actually light from one of the fiercest events in the Universe, and may shine a light -- literally -- on the fate of the cosmos in which we live.'