NASA's Kepler Telescope Good at Finding Extrasolar Planets

The news that a just-discovered planet in the Kepler 22 system has a composition and orbital plane similar to Earth and just may contain an atmosphere and water is exciting. But if a December 5 announcement by NASA researchers turns out to be accurate, Kepler 22b (that's the new planet's name) is just the tip of a very large extraterrestrial iceberg. It seems the Kepler telescope has detected 2,326 potential extrasolar planets and, assuming NASA isn't taking a premature victory lap, an astonishing 99 percent of these potentials may turn out to be the real thing.

The Kepler telescope - technically the Kepler spacecraft observatory - uses a photometer that measures the brightness stars within its fixed field of vision. It therefore cannot take the kind of snapshots with which the Hubble Space Telescope, using giant Cassegrain reflectors to capture extremely sharp photo images, consistently blows the world's minds. Kepler detects possible planets as they orbit in front of a given star, causing a detectable dip in that star's brightness. The size of the dip gives a clue as to the planets size. Once the dip has been detected multiple times, additional observations are made using traditional telescopes

So far the NASA team tasked with going over its collected data have only successfully analyzed 30 of these potentially-thousands of planets. So how then are they already claiming such a high success rate? That's based on additional research overseen by Jean-Michel Desert of the Harvard-Smithsonian Center for Astrophysics. He and his team used the Spitzer Space Telescope - which can see in the infrared spectrum as opposed to Kepler, limited to visible light - to examine 34 Kelper potentials. They found that all potentials are likely real worlds and estimate the Kepler telescope's false positive rate to be less than one percent. A separate study has similarly concluded that so far, Kepler's false positive rate is less than 10 percent.

Before we get too excited about the possibility of Star Trek coming true, it's important to note that Kepler hasn't been tasked with examining close stars such as Alpha Centari. The Kepler 22 system, for instance, is 600 light years away, which means any information we're collecting about Kepler 22b happened during the Hundred Years War. Presumably, Kepler 22b-based historians are currently thrilling to the madcap drinking adventures of young prince Henry and Falstaff.