arXiv 0807.13162008-07-08astro-ph

The MEarth project: searching for transiting habitable super-Earths around nearby M-dwarfs

Jonathan Irwin, David Charbonneau, Philip Nutzman, Emilio Falco

备注：: 7 pages, 5 figures. To appear in the Proceedings of the 253rd IAU Symposium: "Transiting Planets", May 2008, Cambridge, MA
DOI：: 10.1017/S1743921308026215

英文摘要：

Due to their small radii, M-dwarfs are very promising targets to search for transiting super-Earths, with a planet of 2 Earth radii orbiting an M5 dwarf in the habitable zone giving rise to a 0.5% photometric signal, with a period of two weeks. This can be detected from the ground using modest-aperture telescopes by targeting samples of nearby M-dwarfs. Such planets would be very amenable to follow-up studies due to the brightness of the parent stars, and the favourable planet-star flux ratio. MEarth is such a transit survey of ~2000 nearby M-dwarfs. Since the targets are distributed over the entire (Northern) sky, it is necessary to observe them individually, which will be done by using 8 independent 0.4m robotic telescopes, two of which have been in operation since December 2007 at the Fred Lawrence Whipple Observatory (FLWO) located on Mount Hopkins, Arizona. We discuss the survey design and hardware, and report on the current status of the survey, and preliminary results obtained from the commissioning data.

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