The crater of Jezero chosen as landing site for the rover March 2020

NASA's next robot rover will explore a geologically diverse crater that may have already been inundated with water, an essential element of the mission-proof search of past life.

Jezero Crater (bottom center) in the middle of deltas and basins of Mars carved in the water. This spectral analysis of the region combines the data from the Context Camera and the Compact Reconnaissance Imaging Spectrometer on board the Mars reconnaissance orbiter.
NASA / JPL / JHUAPL / MSSS / Brown University.

After a lengthy selection process, NASA chose the Jezero crater in the northern Martian hemisphere as a landing site for its March 2020 rover.

The announcement was made Monday, November 19, after a five-year selection process taking into account more than 60 candidate sites scattered on Mars. As with any landing selection, there is a constant tension between the choice of a safe landing place and one of a scientifically rewarding place.

In early 2017, NASA announced three possible landing sites as possible finalists. Columbia Hills (explored by NASA's Spirit robot until it goes quiet in 2010) and the North Syrtis area northeast of Mars, adjacent to the Jezero Crater. The mission scientists settled in Jezero during the fourth workshop at the March 2020 landing site held last month.

"The landing site in the Jezero crater offers a geologically rich terrain, with terrain shapes dating back to 3.6 billion years, that could potentially answer important evolutionary questions. planetary and geological, "Thomas Zurbuchen (NASA) said in a recent press release. "Getting samples from this unique area will revolutionize the way we think about Mars and its ability to shelter life."

Welcome to the crater of Jezero

Located near latitude 19 ° N and longitude 77.5 ° E in the area of ​​Syrtis Major, the crater of Jezero, with a diameter of 49 km (49 km), seems to have been inundated with water. water early in the history of Mars. targets for the rover, including at least five rock varieties as well as an assortment of carbonates and clays. These are crucial for the mission as the March 2020 rover will specifically look for signs of past and present life on Mars. The crater also seems to have been a turning point for a fan located near the delta, which could have carried material nearby in the crater.

But the crater will also be a difficult place for the landing and operation of the Rover Mars 2020. The crater is littered with smaller impact craters and large rocks. There are also depressions filled with wind-blown sand, spots that could serve as sand traps for a rover.

The red indicates the location of the Jezero crater on the surface of Mars compared to the location of other missions (in yellow) and geological sites (in white).
NASA / JPL / additions by author

Landing planning

The Rover Mars 2020 will land using the celestial crane descent technique invented by the Rover Mars Curiosity, which landed successfully at Gale Crater on August 6, 2012. Since then, researchers have been much better able to predict where Lander will wind up, narrowing the targeted landing zone for the March 2020 rover compared to half that of Curiosity. Unlike Curiosity, the Mars 2020 rover will use a new landing capability called TRN (Terrain Relative Navigation), which will allow it to autonomously analyze the landing site and maneuver to avoid dangerous areas during descent. ASPIRE sub-orbital launches from NASA Wallops in Virginia also tested the downhill parachute for the mission last summer.

The selection of the site is not yet finalized, however. At present, the selection of the Jezero crater depends on the TRN capacity verification analyzes and tests. Mars NASA's Reconnaissance Orbiter will also now map the Jezero crater terrain in more detail. A final report on the site, prepared by an independent review committee, is to be presented to NASA in the fall of 2019.

"The Mars community has long coveted the scientific value of sites such as Jezero Crater," said Ken Farley (NASA-JPL) in a recent press release. "The challenges posed by a safe landing were considered prohibitive, but what was once inaccessible is now conceivable, thanks to the 2020 engineering team and advanced entry technologies, descent and landing on Mars. "

The technicians are working on the descent scene of the Rover March 2020.
NASA / JPL-Caltech

Landing on Mars is difficult, that's for sure. The European Space Agency (ESA) lost its demonstrator Schiaparelli Entry, Descent and Landing in 2016, while it was trying to land on the planet. The lessons learned from this experience will be realized as part of ESA's mission, the ExoMars launcher, also launched in 2020 and destined for the 2021 landing in the Oxia Planum region. on Mars. NASA is actually doing very well in landings on Mars, seven landings since Viking 1 on July 20, 1976, with only one failure, the Mars Polar Lander mission in 1999.

If all goes as planned, March 2020 will launch at the summit of an Atlas V rocket in Cape Canaveral, Florida, in July 2020, for a landing in February 2021. In addition to exploring the crater of Jezero, March 2020 will collect samples for a possible future date return mission. A small helicopter scout will also accompany the rover, a first for any planetary mission.

Let's hope that the Great Galactic Ghoul – a fictional space creature invented to explain Mars's unfortunate missions with an appetite for savory human spaceship – does not know that the March 2020 Rover is heading toward the Jezero Crater.