Jezero crater delta and its minerology
This now-dry river delta sits along the northwestern rim of Jezero crater and contains its own tiny impact crater. The high-resolution gray-scale features were imaged by the Mars Reconnaissance Orbiter (MRO) Context Camera. Colors indicate different minerals identified with spectral data from MRO’s Compact Reconnaissance Imaging Spectrometer for Mars. Green shows carbonates, purple shows iron-magnesium smectite, and orange shows olivine. The delta is about 4 kilometers wide. Credit: NASA/JPL/JHUAPL/MSSS/Brown University

Mars’s Jezero crater, a 45-kilometer-wide impact basin, will soon be home to NASA’s Mars 2020 rover.

A major mission component of Mars 2020 will be to examine whether Jezero crater hosted microbial life in the past.

Jezero crater is also a dry lake bed that contains ample evidence of past water flows, including two inlet rivers, an outlet river valley, and fans and deltas. Recent research has also suggested that the Jezero lake once may have overflowed, burst its edges, and caused significant flooding of the surrounding region. NASA last week announced Jezero as the Mars 2020 landing site.

A major mission component of Mars 2020 will be to examine whether Jezero crater hosted microbial life in the past. The basin’s 4-kilometer-wide river delta, seen in the image above, may have trapped and concentrated microbial life flowing into the crater. Mars scientists suspect that the delta’s sediments and clays might now preserve signs of those ancient microbes in addition to sediments from far away that traveled along the now-dry rivers. Jezero crater is located just north of Mars’s equator.

Site Selection

Elevation map of Jezero crater showing inlet and outlet rivers
A digital elevation model of Jezero crater from the European Space Agency’s Mars Express spacecraft overlies a high-resolution image of the crater from MRO. Warm colors indicate high elevation, and cool colors indicate low elevation. Scientists have identified what used to be two inlet rivers, which can be seen at the western (left) and northwestern (top left) edges of the basin. The Jezero crater delta is located at the mouth of the northwestern inlet river. A deep outlet river valley can be seen at the northeastern (top right) basin edge. Credit: NASA/Timothy Goudge

NASA selected Jezero after more than 5 years of discussion. During a series of workshops, planetary scientists proposed, debated, and narrowed down possible landing sites for NASA to choose from.

The potential sites were judged on geologic and engineering criteria. Scientists considered a site’s compatibility with NASA’s “sky crane” landing method as well as its astrobiological relevance, geologic diversity, water resource potential, and the scientific merit of collecting rock samples.

Jezero excelled across each criterion. “The landing site in Jezero crater offers geologically rich terrain, with landforms reaching as far back as 3.6 billion years old, that could potentially answer important questions in planetary evolution and astrobiology,” Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate, said during last week’s announcement. “Getting samples from this unique area will revolutionize how we think about Mars and its ability to harbor life.”

Toward Launch

The Mars 2020 rover will be able to characterize weather, dust, and environmental conditions on the planet’s surface as well as drill, collect, and store rock samples that may be returned to Earth aboard a future mission. Mars 2020 will also test whether scientists could produce breathable oxygen from Mars’s atmosphere, a feature that may be useful for future human exploration.

Mars 2020 is scheduled to launch from Cape Canaveral Air Force Station in Pensacola, Fla., in the summer of 2020. With more than a year until launch, Mars 2020 mission scientists now plan to finalize the rover’s design and launch details and optimize it to land safely and explore Jezero.

—Kimberly M. S. Cartier (@AstroKimCartier), Staff Writer


Cartier, K. M. S. (2018), Martian crater will be the landing site for a future rover, Eos, 99, Published on 30 November 2018.

Text © 2018. The authors. CC BY-NC-ND 3.0
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