COROT’s discovers its second exoplanet

As a planet passes in front of a star, there is a dip in the light output from the star, which is detected by COROT. Since many other processes can mimic the signature observed, to confirm the presence of a planet, a large confirmation programme with supplementary ground-based observations is necessary to prove the existence of a planet.

Although COROT observes thousands of light curves, the pace of discovery is governed by ground-based observations.

In the third sequence of COROT observations, a likely time for the transit of COROT-exo-2b in front of its star was worked out and an analysis of the light curve was carried out in real-time to confirm the find. Observations were carried out simultaneously at the observatory of Haute Provence in France, and at the European Southern Observatory in Chile, confirming the existence of the planet and its mass was measured.

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So the delay is not in finding light curves that fluctuate, but in confirming them from ground observatories with limited availability...