In addition to loss from high-energy impacts, there is an ongoing debate among scientists as to how much atmospheric loss arises from the impact of the solar wind on the planetary atmosphere, especially in the absence of a planetary magnetic field. All three planets are losing atmosphere to space, even though Earth has a magnetic field and Venus and Mars do not. The extent to which Mars’s lack of magnetic field played a role in its atmosphere loss will be studied by NASA’s MAVEN (Mars Atmosphere and Volatile EvolutioN) mission, scheduled for launch in 2013.