Free Astronomy Magazine March-April 2021

50 MARCH-APRIL 2021 MARS ROVERS T he descent of Perse- verance as captured by the High Resolution Imaging Experiment (HiRISE) camera aboard the Mars Reconnaissance Orbiter. At image left, the mission-target river delta within Jezero Crater. [NASA/JPL-Caltech/Uni- versity of Arizona] geological interest and, for Percy, potential past biological habitability. The chosen location for Percy is Jezero Crater, the focus of an extensive arti- cle in the Jan/Feb 2020 issue. In Mars’ ancient past, Jezero Crater hosted at least one lake into which several rivers flowed, two of which produced accessible for missions that could then launch from a body with a fraction of Earth’s gravity. On Mars, we have accessible water ice for both fuel and drinking, but also a thin atmosphere from which the right equipment could convert carbon dioxide into oxygen – after which the process of compress- ing and storing oxygen for future use is some- thing we already do on Earth every day. This test is being performed within the Mars Oxygen ISRU Ex- periment (MOXIE) to de- termine if future explor- ers could simply make breathable oxygen out of, certainly in the case for Mars, thin air. The delivery of an ad- vanced mobile laboratory to a desolate and fea- tureless location is about as useful as delivering a rover with minimal capa- bilities to an ideal loca- tion. To that end, probes such as the Mars Recon- naissance Orbiter have been used to scour the Martian surface for years in search of locations of great T aken from the descent stage, a snapshot of Perseverance rover from about two meters above the Martian surface. This image was sent down the coiled umbilical into Percy for later transmission before the descent stage disconnected from the rover and flew off to a safe distance. [NASA/JPL-Caltech]