This article originally ran November 15, 2012. We've dusted it off to celebrate the four-year anniversary of Kepler's lift off.--Eds
This week NASA announced its planet-hunter, the Kepler Space Telescope, just completed its primary mission. It’s far from retired--Kepler got a nice long extension back in April, so it will keep staring at distant stars for up to four more years--but it’s still a milestone for NASA and the planet-hunting community. To celebrate its next step, we’re taking a look at some of Kepler’s greatest hits so far.
Click to launch the photo gallery
Since its launch in early 2009, the space telescope has found a treasure trove of new worlds orbiting distant stars, suggesting that planets are plentiful in our galaxy and maybe the universe. It has found so many planets, they’re practically garden variety--really a shocking thing when you sit and think about it. But it should not be this way. Exoplanets are awesome!
The space telescope is orbiting the sun, trailing behind Earth. It was designed to look for other Earths, and it hasn’t found one yet--but it has come very close, as you can see in our slideshow.
“The initial discoveries of the Kepler mission indicate at least a third of the stars have planets and the number of planets in our galaxy must number in the billions,” said William Borucki, Kepler’s principal investigator at NASA's Ames Research Center in Moffett Field, Calif. “The planets of greatest interest are other Earths, and these could already be in the data awaiting analysis. Kepler's most exciting results are yet to come.”
Click here to see some of the best we’ve seen so far.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.