Saturday, March 17, 2007

I Feel Small


I stumbled upon this progressive comparison of the sizes of our planet, our neighboring planets, the sun, our neighboring stars, up to the largest stars.



5 comments:

randy said...

Nick, now don't go all Carl Sagan on us.

Cabeza said...

I've been to Antares once. I didn't think it was that big.

Nick said...

I once started a novel about an Earth colony on a planet orbiting Arcturus. Silly me- there could never be a hospitable planet orbiting a star that big.

(I wrote like 3 pages, then I quit)

randy said...

Why not? Put it at the right distance for enough solar energy, and fast enough so that it doesn't get pulled in by gravity... Wouldn't that work?

Nick said...

Lots of those big stars burn so hot that their peak level of radiation is in the high ultraviolet- so unless you've got a huge ozone layer, your inhabitants either get fried or evolve into beings with high UV tolerance. Also, larger stars like arcturus will only burn for a few million years- some of the larger ones we already know about may have already been burning for several million years (theres no way to tell), and so could blow at any time. You wouldn't want to start a colony in a star system that may shortly become a large black hole.
Another problem is that while the star is very very large, the mass is not proportionally larger, so in order to assure the correct amount of solar radiation the planet would have to be orbiting so far away that it's solar year would be hundreds of our years. That would make seasons rather long (assuming the planet had any tilt). Anyway, its not impossible, but the odds of there being hospitable planets around stars like that are slim, especially considering most of them are binaries, which would mess things up even worse.