h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I started a conversation on that page that I think you should read.

I had a look at that, and am not sure you're right. Fine the /large/ gravity well isn't a problem, but surely the number of large masses is - how would an object circumnavigate three suns?

they don't have to circumnavigate the three stars, they can just orbit one.

think of it this way, You have earth here one AU from the sun (about 15,000,000,000 km). We have a sattlite (the moon) orbiting the Earth in a stable orbit, meaning it's not about to get pulled away by the sun or crash into the Earth. Now the Sun is about 1,000,000 times more massive than the Earth and it doesn't have the gravitational force required to pull the moon from the Earth.

Now imagine the earth was actually a star about the same mass as the sun. It would be able to hold satellites farther away from it than the earth could, because it has more gravity.

the two main sun-like stars of Alpha Centauri are about 23 AU from each other. Since they are farther away from each other they can hold satellites in stable orbits farther away from themselves than if they were 1 aU apart.

Now you are probably wondering about the third star. Alpha Proxima is very far away from the other two stars, and so doesn't really interfere with them.

Here is a website about this.

http://monet.physik.unibas.ch/~schatzer/Alpha-Centauri.html

I mean think of jupiter. It practically has a whole solar system around it, and it is closer to the sun than Alpha Centauri a and b are from each other.

Another thing. Saturn doesn't pull moons from jupiter in conjunction with the sun either. Do you see what I mean?

oh okay...
I will try to get round to 'updating' it - though it does sound like I'm just going to have to chop a bit out!

I have already brought this to the attention of Mark and Yoz, and they asked me for some text to replace the incorrect stuff. So you might want to talk to them first.

Erm... okay then. I'll have a look at that... Mark and Yoz have even less time than I do, but it will get done eventually....