jezero crater map

On Monday, at the end of a five-year process, NASA officially selected Jezero Crater as the future home of the Mars 2020 rover. After scrutinizing over 60 locations, as well as a confusing vote following the final landing site workshop in late October, #TeamJezero scientists rejoiced.

Jezero wasn’t a clear shoo-in. The final landing site workshop closed with essentially a three-way tie among Jezero Crater, NE Syrtis, and Midway, a site between the two. The tie left NASA with an interesting decision: either visit one of the sites or go on a mega-mission from one of the sites and Midway.

four sites mars landing
The final four sites in question.

Ultimately, the space agency committed to the 28-mile wide, 500-meter-deep crater located in a basin slightly north of the Martian equator. Jezero Crater fulfills the basic requirements of a survivable landing site, including a location closer to the equator for milder seasons and consistent access to sunlight for its solar panels.

Two Habitable Environments for the Price of One

The soil science at Jezero Crater caught scientists’ attention. First identified in 2005, the crater once housed a lake estimated to have dried out 3.5 to 3.8 billion years ago (hence the name Jezero, which translates to “lake” in several Slavic languages). Thanks to the two channels that once supplied it with water, the site holds not only a rich supply of clays and carbonates — which have high potential for preserving biosignatures — but also hints about the surrounding area.

Taking a closer look at the site’s history through rock layers, researchers also determined that Jezero Crater experienced two different periods of watery activity. Since the general consensus holds that life can’t exist without water, on the search for extraterrestrial life, we look for traces of it. And two watery eras mean two different chances for Martian life to have existed. Scientists get to analyze two potential life-sustaining environments for the $2.1 billion price of one!

Mars meteorite
In the Mars 2020 mission, scientists hope to bring back samples of our own choosing, contributing to fragments collected from meteorites. A slice of Martian meteorite will travel on the Mars 2020 rover.

Ideally, Jezero crater’s soil will make up the first Martian samples ever returned to Earth. To make this job possible, the still-nameless rover is equipped with 43 sample containers. Over the course of several years, future missions would return these soil souvenirs into the hands of eager scientists.

With such promising geology comes an extra challenge to the already-hazardous landing process — to the east of Jezero Crater lie boulders and rocks, and to the west, a cliff. Several pockets of aeolian bedforms (Mars dunes) scattered between could trap the unsuspecting rover.

Previously, scientists considered Jezero too difficult to reach, but NASA project scientist Ken Farley said in a statement that the long-coveted site is no longer just a dream: “What was once out of reach is now conceivable, thanks to the 2020 engineering team and advances in Mars entry, descent and landing technologies.”

landing site gif selection
Mars 2020 rover landing sites. This animation shows three potential sites, but a fourth contender was added in July, called Midway (located between NE Syrtis and Jezero Crater).

What’s Next

For the Mars 2020 mission, the rover will explore the history of Mars’ environment, look for evidence of past life (which will inform whether future life could reside there), take the aforementioned samples that may one day be returned to Earth, and take measurements in preparation for a crewed mission. NASA plans to launch on July 17, 2020.

One by one, the details of the Mars 2020 rover and it’s mission are falling in place. Landing site? Check. Now, we wait for NASA to open the competition students K-12 are waiting for in the next year: naming the rover itself.

Related Video: Meet the Mars 2020 Rover