  The Mars thermosphere holds clues to the evolution of the Martian climate,
and has practical implications for spacecraft visiting Mars, which often use it
for aerobraking upon arrival, or for landers, which must pass through it.
Nevertheless, it has been sparsely characterized, even when past accelerometer
measurements and remote observations are taken into account. The Mars
Atmosphere and Volatile EvolutioN (MAVEN) orbiter, which includes a number of
instruments designed to characterize the thermosphere, has greatly expanded the
available thermospheric observations. This paper presents new and unanticipated
measurements of density and temperature profiles (120-200 km) derived from
solar occultations using the MAVEN Extreme Ultraviolet (EUV) Monitor. These new
measurements complement and expand MAVEN's intended thermospheric measurement
capacity. In particular, because the local-time is inherently fixed to the
terminator, solar occultations are ideally suited for characterizing long-term
and latitudinal variability. Occultation measurements are made during
approximately half of all orbits, resulting in thousands of new thermospheric
profiles. The density retrieval method is presented in detail, including an
uncertainty analysis. Altitude-latitude maps of thermospheric density and
temperature at perihelion and aphelion are presented, revealing structures that
have not been previously observed. Tracers of atmospheric dynamics are also
observed, including a high altitude polar warming feature at intermediate
latitudes, and an apparent thermostatic response to solar EUV heating during a
solar rotation, which shows heating at high altitudes that is accompanied by
cooling at lower altitudes.
