Planet Hunt 
Astronomers around the world are devoting a lot of attention to several hundred stars these days. A NASA satellite has found evidence that planets might orbit these stars. But additional observations by ground-based telescopes are needed to confirm which ones really have planets.
The Kepler mission is keeping a constant eye on more than 150,000 stars in the constellations Cygnus and Lyra. They're high overhead at nightfall, marked by their brightest stars, Deneb and Vega -- two points of the bright Summer Triangle.
Kepler is looking for tiny dips in the brightness of these stars caused by planets passing directly in front of them. Its goal is to find Earth-like planets in Earth-like orbits around Sun-like stars. But it hasn't been in space long enough yet to confirm any such discoveries -- it's a process that will take a few years.
In the meantime, it is finding other types of planets -- planets that orbit close to their parent stars. Earlier this year, for example, Kepler scientists confirmed the discovery of five such worlds.
And a few months later, the project released several weeks of Kepler observations to other astronomers. The observations contain many possible planet discoveries. But some of the observations could be false alarms. So astronomers are checking out each of the stars -- a process that could potentially yield hundreds of new planets over the coming months.
More about Kepler tomorrow.
Script by Damond Benningfield, Copyright 2010
This program was made possible in part by a grant from NASA.