NASA Solicits Proposals for a World-class Precision Doppler Spectrometer at Kitt Peak National Observatory

Very high velocity precision is needed to measure the mass of low mass planets through the subtle motion, the “wobble”, that a planet induces in its host star. The extreme precision radial velocity spectrometer (EPDS) destined for Kitt Peak will measure stellar motions with a precision of 0.1 - 0.5 m/s (or 0.2 - 1 mph), velocities comparable to the running speed of a desert tortoise or gila monster. With such high precision, the spectrometer will be able to detect and characterize Jupiter- and Neptune-sized gas giant planets as well as super-Earth and Earth-sized rocky planets.