MA-MISS: Mars multispectral imager for subsurface studies

The Italian drill "DEEDRI" is going to be the lander based sample acquisition system for the Mars Surveyor Program of the Mars Sample Return mission. DEEDRI is capable to collect core/sand sample of the martian soil down to 50 cm in depth. The MA_MISS experiment belongs to the DEEDRI system and it will be dedicated to observe the wall of the excavated hole in terms of infrared spectral reflectance in the range 0.8-2.8 mum. The spectral sampling is about 20 nm while the spatial sampling is 100 mum over the target. The optical window of MA_MISS is placed very close to the drill tip so that the target view to be observed can span from the soil down to 50 cm. The proximity optics and electronics of MA_MISS have to be very miniaturized since they will be collocated inside the drill tool in a very limited volume of about 25 mm in diameter. On the other side the main electronics will be on the lander and it will communicate through an interface based on slip rings devices. MA_MISS can acquire in different observation modes. The images are scanned by moving the DEEDRI itself. One image ring is built up by acquiring contiguous images of the MA_MISS slit. The study of the Martian subsurface will provide important constraints on the nature, timing and duration of alteration and sedimentation processes on Mars, as well as on the complex interactions between the surface and the atmosphere. This study will permit to infer the history of erosion, transport and deposition of loose material. Alteration processes can dominate the mineralogy of the Martian surface: it will be essential to study the mineralogy of deeper layers, where a more limited alteration took place, MA_MISS can provide very important scientific return from the subsurface of Mars along with a selection criteria for the samples collection. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.