Now well into the assembly and testing phase, NASA's next Mars mission is on track for a July 2020 launch. We already know its mission goals and which instruments it's taking to try to achieve them, and now we're now a little closer to learning where touch down will take place. After a workshop last week, NASA has revealed that three potential landing sites have been shortlisted: Northeast Syrtis, Jezero Crater and Columbia Hills.

Announced soon after Curiosity landed on the Red Planet's surface in 2012, the Mars 2020 rover will build on the design and findings of its predecessor. The rover's primary mission is focused on determining whether Mars ever hosted life in the past or ever could in the future. To that end, the mission will conduct geological assessments to search for the remains of ancient Martian microbes, study how habitable the planet could be for future manned missions, identify resources that human explorers could make use of, and potential hazards to avoid.

With an entire planet to explore, picking the right landing site is crucial to the mission's success. Obviously, it needs to be somewhere a rover could safely touch down and drive around, but the site needs to satisfy a few key geological criteria as well. A history of liquid water is important, as is the presence of a variety of rocks and soil, as some types can preserve signs of life for longer than others.

With these goals in mind, NASA held a conference last week to narrow down a list of eight sites, decided on in August 2015, to the three best candidates.

Columbia Hills

If the Mars 2020 rover visits this section of the Gusev crater, it could pay its respects to its ancestor, the Spirit rover, which touched down nearby in 2004 and went offline in 2010. Although much of the crater had proven dishearteningly dry, one of Spirit's biggest discoveries was that Columbia Hills was likely once home to hot mineral springs. That watery history, plus the fact that the terrain has already proven itself suitable for a rover, makes this a good spot to dig a little deeper into Mars' past.

Jezero Crater

This spot seems to have a wet and wild history. At some point in the past, the crater is believed to have been filled with water, then drained, then filled again, giving life ample time to have moved in. The thick layer of clay in and around the crater is a very promising sign because not only does it usually only form in the presence of water, but it's good at preserving signs of life.

Northeast Syrtis

Relatively close to Jezero Crater, Northeast Syrtis could once have been a literal hotspot for microbes. Life loves volcanic areas, and here, heat radiating up from underground might have melted surface ice and formed hot springs. Its layered terrain is ripe for geological study and may help paint a vivid picture of early Mars.

There's no word yet on when NASA will pick the winning landing site.

Source: NASA

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