Earth-size planet discovered in the nearest solar system

We’ve all heard of Alpha Centauri, the closest star (or rather it’s a triple star, three stars in a single orbital system) to our solar system, “only” 4.4 light-years away. As reported in today’s New York Times, scientists have just discovered a small planet the same size as our Earth revolving around one of the Alpha Centauri stars:

The planet is the lightest one ever found orbiting another star and—in the words of its discoverer, Xavier Dumusque, a graduate student at the Geneva Observatory—“it will surely be the closest one ever.”

It is presumably a rocky ball like our own, but it is not habitable. It circles Alpha Centauri B, a reddish orb about half as luminous as the Sun, every three days at a distance of only about four million miles, resulting in hellish surface temperatures of 1,200 degrees.

If the closest star to ours has a planet, then planets must be extremely common. Perhaps, just as stars seem to evolve automatically from a universe consisting of nothing but hydrogen and helium atoms (see Wikipedia on stellar evolution), resulting in a universe filled with stars and galaxies, perhaps planets automatically evolve out of stars, so that planets, instead of being relatively rare, accompany almost every star.

Posted by Lawrence Auster at October 17, 2012 12:20 PM | Send