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Abstract :
[en] The Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft occasionally has close encounter seasons with Phobos as a consequence of its orbital precession and its apoapsis being near the orbit of the moon. During one encounter season in late 2015, MAVEN's Imaging Ultraviolet Spectrograph (IUVS) was able to gather the first ever spectral images of the moon in the mid-ultraviolet. During these flybys, IUVS was able to observe the trailing hemisphere of the moon, producing spectra useful for comparison with the Mariner 9 Ultraviolet Spectrometer measurements, which observed only the moon's leading side. The IUVS data reveal that the trailing side of the Moon is bluer than the leading side, indicating possible differences in the weathering history of the hemispheres. In addition, we see some evidence for an absorption feature longward of 300 nm, potentially produced by organic compounds, in accordance with Mariner 9 and SPICAM/UV observations. We will present an overview of our images and spectra and a discussion of their interpretation for the history and formation of Phobos.