Apparently the probes are running too low on fuel, forcing NASA to cut their journey short. Ebb and Flow, which started flying around the Moon since January this year, produced the highest resolution gravity map gathered from a celestial body. This will enable NASA to better understand how Earth and other rocky planets form and evolve. “We’re not expecting a big David Lehman, the Project Manager of NASA’s Jet Propulsion Laboratory. “Their fuel tank will be empty and they are the size of a washing machine.”