NASA Ready for Its Newest Rover to Land on Mars

In less than 24 hours, NASA’s latest rover will land on Mars. With an 11 minute time delay, the Mars Perseverance rover will be on its own as it descends through the Mars atmosphere during “Seven Minutes of Terror” when everything must go just right for it to settle gently at Jezero Crater. In addition to an array of scientific instruments, Perseverance is carrying a tiny helicopter, Ingenuity, that will be the first aerial vehicle to fly on another planet and a system to collect samples that will be returned to Earth by later missions.

Originally known simply as Mars 2020 after its year of launch, NASA named it Perseverance through a student essay contest won by Alex Mather of Springfield, VA in March 2020.  No one realized at the time how apt the moniker would be as the COVID-19 pandemic complicated the final months of getting the rover ready for launch on July 30 last year on a United Launch Alliance Atlas V rocket. Through those early months of quarantines and restricted travel, the Perseverance team did indeed persevere.

Tomorrow, the spacecraft finally arrives at its destination. Landing is expected about 3:55 pm Eastern Standard Time.  NASA will carry the landing live on its TV and other media outlets beginning at 2:15 pm EST.

Perseverance will have to endure the same Seven Minutes of Terror entry-descent-and-landing (EDL) sequence as its cousin, Curiosity, in 2012.

The perilous trip from the top of the Martian atmosphere to the surface entails many risks starting with opening its parachute at supersonic speeds. Allen Chen, the EDL landing lead at NASA’s Jet Propulsion Laboratory (JPL), said at a news briefing today that a “lot of concentrated risk” is in that one action.  “That is a very big parachute … that’s the size of a little league infield in size, and that snaps open in about point six seconds, while going almost Mach two.”  But it has been rigorously tested, instilling confidence that it will do its job tomorrow.

One difference from Curiosity is that Perseverance will make a more precise landing in the 45-kilometer (28-mile) wide landing ellipse using a Terrain-Relative Navigation system. NASA’s Mars Reconnaissance Orbiter (MRO) has been making detailed images of the Martian surface since 2006, yielding a detailed map of Jezero Crater that is loaded in Perseverance’s computer.  During descent, it will compare what it sees with its onboard cameras to the map and navigate exactly to the right spot.

NASA chose Jezero Crater not because it is a safe landing place with lots of open space. Quite the opposite. An ancient river delta, it features steep cliffs, sand dunes and fields of boulders — a scientific treasure trove, but a tough location to set down.  Chen ruefully called it a place “full of the stuff that the scientists want to see, but the stuff I don’t want to land on.”

Eight NASA missions have successfully landed on Mars so far, including four rovers:  Viking 1 and 2 (stationary landers), Mars Pathfinder and its Sojourner rover, the Spirit and Opportunity rovers, Phoenix (stationary), the Curiosity rover, and InSight (stationary). But it is a difficult feat and the 1999 Mars Polar Lander failure is a reminder that things can go wrong.  Soviet and European landing attempts also have not had happy endings.

“If you don’t stay humble in this business and especially going to Mars, you’re going to pay for it,” Chen cautioned.

During descent and on the surface, Perseverance will communicate with Earth using its own antennas as well as through spacecraft orbiting Mars. NASA’s MRO and Mars Odyssey, as well as the European Space Agency’s (ESA’s) Mars Express and ExoMars Trace Gas Orbiter (TGO) can relay signals.

Find out how #Mars Express & #ExoMars @ESA_TGO are also helping support @NASAPersevere landing tomorrow by monitoring weather conditions at the landing site and providing data relay services ?https://t.co/2Enbj4iLHv#CountdowntoMars #ExploreFarther #Teamwork ? pic.twitter.com/ai4RLnaJce

— ESA Science (@esascience) February 17, 2021

Perseverance is primarily a science mission to determine whether Mars may once have supported life and to characterize its climate and geology.  It is the first of three missions in a joint NASA-ESA effort to return samples of Mars to Earth.  Perseverance will collect samples in cigar-shaped tubes and leave them on the surface. Later this decade, NASA and ESA will launch two more missions — a Sample Fetch Rover and an Earth Return Orbiter — to collect and bring them back to Earth.  Using instruments on Perseverance and eventually studies of those samples, scientists hope to determine if microbial life once existed there.

But it is also tied into NASA’s plan to someday send humans to Mars.  Another experiment, MOXIE, will try to convert carbon dioxide in the Martian atmosphere into oxygen, important to support astronauts and as rocket propellant.

Perseverance is chock full of instruments, cameras and experiments, but one particularly unique passenger is a tiny 1.8 kilogram (4 pound) helicopter named Ingenuity.  A technology demonstration, it will be the first aerial vehicle to fly on another planet. The extremely thin atmosphere and one-third gravity of Mars makes it a particularly challenging feat. Buttoned up in Perseverance’s belly, Ingenuity will be lowered to the surface and after the rover backs away, take flight.