SCIENCE
01/19/2012 02:22 pm ET

Amateur Astronomer Discovers Planet Orbiting Distant Star

There are billions of planets in our galaxy, and a hot, Neptune-sized planet orbiting an ordinary star called SPH10066540 might not seem unusual, but there's a catch. It was discovered by an amateur, with only "a passing interest in where things are in the sky."

That's how Chris Holmes, from Peterborough, England, described himself when he spoke to the BBC about his discovery. "I've never had a telescope," he added, and besides a little idle fascination he's "never had any more knowledge about it than that."

Holmes found the planet while looking through data on Planet Hunters, a popular citizen science project that lets ordinary people help scientists navigate through readings from NASA's Kepler telescope.

It turns out that humans can be much better than computers at detecting telltale signs of planets orbiting around stars Kepler has observed. A star that has a planet orbiting around it will dim slightly at regular intervals, and computers sometimes ignore such subtle signals; Planet Hunters gives people a visual display of a star's brightness over time, and the signs of a planet can be quite clear (see above image) if you know what to look for.

Never before have people been able to discover planets without knowing astrophysics; the simplicity of looking and the possibility of actually finding a planet have drawn over 100,000 volunteers to go through Kepler data on Planet Hunters. In a 48-hour period, the volunteers looked at over 1 million stars, processing the data with much better eyes than the best computers.

Chris Lintott, an astrophysicist at Oxford University who helps organize Planet Hunters, didn't expect the massive response, saying: "We're ecstatic. We've been groaning under the strain of all these people who want to help us, which is exactly how it should be."

Holmes' planet is too hot to support life, but it's only the first in what will likely be a series of planets the Planet Hunters help discover, and the Kepler telescope has already found one potentially earthlike planet.

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