'What's a Supernova?' - a Pretty Good Overview

Caution! Geeky content!

"What Is A Supernova?"
Space. com (May 4, 2009)

"A blindingly bright star bursts into view in a corner of the night sky — it wasn't there just a few hours ago, but now it burns like a beacon.

"That bright star isn't actually a star, at least not anymore. The brilliant point of light is the explosion of a star that has reached the end of its life, otherwise known as a supernova.

"Supernovas can briefly outshine entire galaxies and radiate more energy than our sun will in its entire lifetime. They're also the primary source of heavy elements in the universe.

"On average, a supernova will occur about once every 50 years in a galaxy the size of the Milky Way. Put another way, a star explodes every second or so somewhere in the universe...."

I'll admit it: what's in this article won't help you make more money, brush your teeth, or clear clogged drains.

But I think the way the universe works is interesting - and maybe you do, too.

This article is a pretty good review, or introduction, to the two main types of supernovas: what they are, how they work, and what they do (make heavy elements and release a whole lot of energy in the process, mostly).

That photo shows the Cassiopeia A supernova remnant: the youngest of its kind known in the Milky Way galaxy. It shows what the remnant looks like in x-rays, transposed down to the sort of electromagnetic radiation we can see.