The MEarth project: searching for transitinghabitable super-Earth planets around nearbyM-dwarfs

摘要

Due to their small radii, M-dwarfs are very promising targets to search for transitingsuper-Earths, with a planet of 2 Earth radii orbiting an M5 dwarf in the habitable zone giving rise toa 0.5% photometric signal, with a period of two weeks. This can be detected from the ground usingmodest-aperture telescopes by targeting samples of nearby M-dwarfs. Such planets would be veryamenable 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 aredistributed over the entire (Northern) sky, it is necessary to observe them individually, which willbe done by using 8 independent 0.4m robotic telescopes, two of which have been in operation sinceDecember 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.