NASA’s science rover ___1___, the most advanced astrobiology laboratory ever sent to another world, streaked through the Martian atmosphere on 19feb 2021 and landed safely on the floor of a vast crater, its first stop on a search for traces of ancient microbial life on the Red Planet.
NASA scientists have described ____1___ as the most ambitious of nearly 20 U.S. missions to Mars dating back to the Mariner spacecraft’s 1965 fly-by.

Larger and packed with more instruments than the four Mars rovers preceding it is set to build on previous findings that liquid water once flowed on the Martian surface and that carbon and other minerals altered by water and considered precurors to the evolution of life were present.

The multi-stage spacecraft carrying the rover soared into the top of Martian atmosphere at nearly 16 times the speed of sound on Earth, angled to produce aerodynamic lift while jet thrusters adjusted its trajectory. A jarring, supersonic parachute inflation further slowed the descent, giving way to deployment of a rocket-powered “sky crane” vehicle that flew to a safe landing spot, lowered the rover on tethers, then flew off to crash a safe distance away.

immediate predecessor, the rover ___2____, landed in 2012 and remains in operation, as does the stationary lander ____3____, which arrived in 2018 to study the deep interior of Mars.
Last week, separate probes launched by the United Arab Emirates and China reached Martian orbit. NASA has three Mars satellites still in orbit, along with two from the European Space Agency.