© NASAKepler's computer has mysteriously entered a standby, or "safe", mode twice since launch - possibly because it was hit by charged particles from space called cosmic rays
The planet-hunting Kepler space telescope has found its first extrasolar planets: three alien worlds that had been previously discovered with ground-based telescopes. The finds confirm that Kepler's instruments are sensitive enough to detect Earth-like planets around sun-like stars - but they might also be unexpectedly sensitive to charged particles in space that can zap circuitry.
Kepler
launched on 6 March with a simple charge: Stare at a swatch of sky for three and a half years, and look for Earths. The telescope will hunt transiting exoplanets, planets that pass in front of their stars and dim their brightness at regular intervals.
It's focused on a 100-square-degree patch of the Milky Way between the constellations Cygnus and Lyra that contains about 4.5 million stars, 100,000 of which are prime candidates for planets.
In the first 10 days of its calibration period, Kepler collected data on 52,496 stars, three of which were known to have transiting planets. "We expected to be able to see those instantly from the first data that we took," says project manager Jim Fanson at NASA's Jet Propulsion Laboratory. "Any planet that you can detect from the ground will be very obviously visible to Kepler."
One of these planets,
HAT-P-7b, provided some good news: Kepler is indeed sensitive enough to detect alien Earths.
