The CoRoT Mission

The French “COnvection, ROtation and planetary Transits”-satellite (CoRoT), is currently using photometry—measuring the intensity of an object’s radiation, in this case at the optical range—to search for extra-solar planets. Starting in 2001 and launched in 2006, the mission hopes to monitor about 30,000-60,000 stars overall. Because of its high photometric accuracy, CoRoT is discovering Neptune- and Uranus-like planets and is attempting to detect large terrestrial planets, down to approximately 2 Earth radii. This year, CoRoT has picked up signals as small as 5 parts in ten thousand. If these signals are a planet’s “transit”—the event of the planet moving between its star and the CoRoT satellite—the planet’s radius would be 1.7 Earth radii. Although astronomers have yet to confirm the “planetary nature” of the signal, this discovery is providing the next step in Earth-sized planet detection.