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تسجيل مستخدم جديدPrecision Space Astrometry as a Tool to Find Earth-like Exoplanets
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Because of the recent technological advances, the key technologies needed for precision space optical astrometry are now in hand. The Microarcsecond Astrometry Probe (MAP) mission concept is designed to find 1 Earth mass planets at 1AU orbit (scaled to solar luminosity) around the nearest ~90 FGK stars. The MAP payload includes i) a single three-mirror anastigmatic telescope with a 1-m primary mirror and metrology subsystems, and ii) a camera. The camera focal plane consists of 42 detectors, providing a Nyquist sampled FOV of 0.4-deg. Its metrology subsystems ensure that MAP can achieve the 0.8 uas astrometric precision in 1 hr, which is required to detect Earth-like exoplanets in our stellar neighborhood. MAP mission could provide ~10 specific targets for a much larger coronagraphic mission that would measure its spectra. We argue for the development of the space astrometric missions capable of finding Earth-2.0. Given the current technology readiness such missions relying on precision astrometry could be flown in the next decade, perhaps in collaboration with other national space agencies.
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