Jezero Crater is a ~45km crater near the Nili Fossae region which is believed to have once been flooded with water. The crater consists of a fan-delta system that deposited rich clays in the area. An important detail for us to compare Mars’s geography to Earths; like the Mississippi Delta which found little organisms imbedded into the rock, a sign that there could also have been life imbedded into the Mars rock in the delta region. This occurs because of a “drop off” area; when the water would flow in, the minerals would stop and “drop off” into the bedding, making life and organisms able to embed themselves in the rock. This knowledge that there could have been life on Mars makes this region a good choice of landing area for the Mars 2020 Rover mission to search for signs of life.
The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad.
CRISM's mission: Find the spectral fingerprints of aqueous and hydrothermal deposits and map the geology, composition and stratigraphy of surface features. The instrument also tracks seasonal variations in dust and ice aerosols in the Martian atmosphere, and water content in surface materials — leading to new understanding of the climate.