With PlanetHunters, you may become the first to know that a star has a companion, just as our Sun does.

What is PlanetHunters?

NASA’s Kepler spacecraft is one of the most powerful tools for searching exoplanets. Approximately every 30 minutes, Kepler monitors the brightness of several thousands of stars simultaneously. Computers sift through the data obtained by Kepler to look for a repeating signal of a planet, but there are planets that can only be found by the human ability of pattern recognition. No training is required! All you need is your eyes and a web browser to join the hunt. It's possible that you may be the first to know that a star somewhere in the Milky Way has a companion. Fancy giving it a try?

What do you do?

You have to draw boxes to mark the locations of the dips on a star’s light curve, which correspond to the measurements of the star’s brightness over time. The depth of the dip and how often it repeats tells about the relative size of the planet and its orbital period (how long the planet year is).

Relations with school topics

Exoplanets, stars, the science of astronomy

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Citizen Science
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