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Once Written Off, Kepler Telescope Finds New Planet

By Bill Chappell

Published December 18, 2014 at 8:05 PM EST

NASA

An artist's rendering shows the Kepler spacecraft in its new mission profile, called K2. The space telescope has found a new planet outside our solar system.

More than a year after NASA said its Kepler space telescope was beyond repair, the planet-hunting probe has delivered an unlikely find: a planet that's outside our solar system. The find comes after a team worked to find a way to make Kepler productive again, says NASA, calling the find "a comeback."

The space agency says the newly discovered exoplanet is 2.5 times the diameter of the Earth – and that the lead researcher on the project is a graduate student at the Harvard-Smithsonian Center for Astrophysics.

That would be Andrew Vanderburg, who found the planet using publicly available data collected by Kepler in February, as the spacecraft was being reconfigured into what NASA calls its new "K2" mission profile.

"Like a phoenix rising from the ashes, Kepler has been reborn and is continuing to make discoveries. Even better, the planet it found is ripe for follow-up studies," Vanderburg said today.

NASA says that the planet, named HIP 116454b, "follows a close, nine-day orbit around a star that is smaller and cooler than our sun, making the planet too hot for life as we know it. HIP 116454b and its star are 180 light-years from Earth, toward the constellation Pisces."

"The discovery was confirmed with measurements taken by the HARPS-North spectrograph of the Telescopio Nazionale Galileo in the Canary Islands," NASA says, "which captured the wobble of the star caused by the planet's gravitational tug as it orbits."

You might recall that Kepler, which cost some $600 million, was feared to be at the end of its useful life in 2013, just four years after it was launched. Two of its four gyroscope-type reaction wheels weren't working well, meaning the observatory couldn't stare at areas of space steadily enough.

"Rather than giving up on the stalwart spacecraft," NASA says, "a team of scientists and engineers crafted a resourceful strategy to use pressure from sunlight as a 'virtual reaction wheel' to help control the spacecraft."

All the while, Kepler has been trailing behind the Earth as it orbits the sun.

Kepler has been responsible for the confirmed discovery of 996 planets and more than 4,100 planet candidates. A "bonanza" of those worlds came in February, when NASA unveiled 715 newly discovered planets.

"The Kepler mission showed us that planets larger in size than Earth and smaller than Neptune are common in the galaxy, yet they are absent in our solar system," said Kepler/K2 project scientist Steve Howell of NASA's Ames Research Center in California. "K2 is uniquely positioned to dramatically refine our understanding of these alien worlds and further define the boundary between rocky worlds like Earth and ice giants like Neptune."