The Planet-Finding Kepler Telescope Lives Again

NASA’s Kepler Space Telescope, the best planet-finding tool mankind has ever made, has spent exactly one year aimlessly orbiting the Earth, its lenses pointing at nothing in particular after a broken reaction wheel had rendered it nothing more than a big piece of space junk. But not for much longer: Today, the space agency announced it would bring the telescope back to life.

NASA has decided to fund the K2 mission, a plan to look for exoplanets along Earth’s ecliptic plane—the line along Earth’s orbit. If everything goes smoothly, Kepler will begin looking for planets again by the end of the month and will operate for at least two more years. If it works, scientists on the project estimate that the telescope has roughly seven years worth of fuel left.

Kepler has already been one of NASA’s most successful projects—it’s found a confirmed 962 planets (including a huge chunk of 715 new ones verified earlier this year), 3,845 planet candidates, and already has enough data to keep researchers busy for years. But after its navigation wheel, which allows the telescope to actually be aimed at specific portions of the sky, broke last year, most people thought the telescope’s useful life had ended.

But glimmers of hope started arising late last year, when Charlie Sobeck, deputy project manager of Kepler, announced the K2 mission. The only question was whether NASA’s higher ups would think it was worth funding. In its senior review, the administration suggested that the team had found an “innovative way of operating the observatory pointing along the ecliptic makes possible long-term high precision photometric observations of galactic and extragalactic sources as well as some solar system objects.”

That’s good news for the Kepler team, but bad news for people looking for potentially habitable planets. With just two wheels, it’ll be nearly impossible to keep Kepler pointed at any one point in the sky—instead, it’ll do a “transit survey,” basically panning different tracts of the the sky for 60 days at a time. In doing so, it’ll be able to detect gas and ice giants, but will probably miss out on most of the small, rocky planets.

Still, the agency believes that, overall, K2 is “an outstanding mission” and one that won’t cost much to keep running. Kepler is coming back to life.