Supernova, Red Giant

I watched a show on the National Geographic channel last night about the Hubble telescope and, man, the pictures it's sending back are awesome. And the things I learned! I know I've heard all this before but, for some reason, it didn't stick. Until now. What I learned:

* The Crab Nebula (who hasn't heard of this, right?) is the result of a supernova that occurred in 1054.
* The stuff flung out into space as the result of a supernova contains the building blocks of new stars, new planets, new galaxies.
* Supernovas occur when a star (like our own sun) runs out of fuel and explodes.
* Estimates are that our sun will run out of fuel in about 5 billion years. Seems we ought to have figured out how to hop a spaceship to another galaxy by then!
*Our sun won't explode, though, because it's too small (supernovas result from stars that are - at a minimum - 4 times larger than our sun). Instead, our sun will turn into a Red Giant: it will heat up and expand outward, causing temperatures on Earth to reach 1000 degrees. As it continues to expand, it will incinerate the planets, one by one, until it engulfs the entire solar system.

I know this stuff isn't for everyone (my husband walked out of the room after watching just 5 minutes!), but it flips my trigger as they say. The possibilities! The things we don't yet know! The things we can't yet see: dark matter (the stuff that holds galaxies and universes together), dark energy (the stuff that's causing the universe to expand). Maybe I should have been a scientist.