In one of Isaac Asimov's non-fiction books (and he's written a whole bunch of them, in addition to his science fiction), he describes a possible Earth-like planet in the Alpha Centauri system. Sounds like a most interesting place, should such actually exist.

The Alpha Centauri system consists of a yellow main-sequence star very much like our sun, but about 20% larger. The second star in the system, Alpha Centauri B, is also main-sequence, but somewhat smaller and cooler. It lies about as far out from Alpha Centauri A as Uranus lies from our sun. Proxima Centauri (Alpha Centauri C), the third star, is a red dwarf, and it lies way out from the other two.

If you were to stuff an Earth-like planet into the system, say, orbiting Alpha Centauri A somewhat further out than the Earth orbits the sun (almost as far out as Mars, perhaps), it would lie in the "temperate zone," where water would be in a liquid form. We could quite probably live there very comfortably. The orbit might be a bit egg-shaped, getting pulled toward Alpha Centauri B as Alpha A, the planet, and Alpha B came into conjunction, but that wouldn't drastically affect the livability of the place for humans. There might be some interesting seasonal variations.

Alpha B would circumnavigate Alpha A about once every eighty years (Earth years), as Uranus orbits our sun. At times, there would be two suns in the daytime sky, and at other times of the year, Alpha B would be in the night sky. Asimov says that it would be bright enough so you could read a newspaper by its light.

Proxima Centauri is far enough out so it would appear as a bright red star, but not as another sun. If you were to look toward the constellation Cassiopeia, you'd notice that it contains one star too many. That would be our sun.

It was some time after I read Asimov's description that I found THIS, which pretty shows what he was describing.

Don Firth