Small(ish) Planet Found in Star's Habitable Zone

The planets we find keep getting smaller. The newest one, which was recently discovered by the Kepler planet hunting telescope, is called Kepler-22b. And that planet is a measly 2.2 times the size of earth, making it one of the smallest planets ever found.

Did I mention it also sits inside its sun’s habitable zone?

The Goldilocks zone is the humorous name given to the region of space surrounding a star where water neither boils off from the heat nor freezes solid from the cold. If a planet orbits in the Goldilocks zone, then it could theoretically have liquid water. that is not guaranteed, of course.

Depending on the planet’s development it could be perfectly dry, or it could mirror either Mars or Venus, both of which are just inside the Goldilocks zone of our sun. But any time a planet is in the Goldilocks zone, it could have surface water.

Hunting for Planets

Finding planets around distant stars is hard. For years scientists discounted ever being able to find them, believing them to be rare and impossible to see. But by relying on clever processing techniques, a few early pioneering researchers managed to prove that there were, at least, gas giants circling a few stars.

Since then planets have come flooding in. Almost every star we point our telescopes at we find planets circling. But most are still gas giants, because our discovery techniques have trouble finding smaller, lighter planets.

As time has marched, however, our techniques have improved and we are now able to spot planets only a little bigger than earth. One of which is Kepler-22b, in the Goldilocks zone of a G type star, meaning that it resembles the sun--a rare trait among stars.

While it will be quite a while before we can get the resolution to actually see the planet, knowing that small, earth-like planets are out there is a boon for science. Every earth-like planet we find is another where life like our own could evolve.

NewScientist Photo by : NASA