Tango Delta! Perseverance Rover touchdown

 Copyright © Françoise Herrmann

On February 18, 2021, the six-wheeled Perseverance Rover vehicle landed on the Jezero Crater, on planet Mars, within a few feet of the targeted spot, 330 million miles away from planet Earth, after departing, on July 30th, 2020, inside a cruise shell, attached to an Atlas V-451 rocket, launched from Cape Canaveral Air Force Station, in Florida. The Perseverance Rover, affectionately called “Percy” is a 2,263-pound (1,026-kilogram), car-size, robotic geologist and astrobiologist, designed to investigate, for the next two years, the geology of the Jezero Crater, an ancient lakebed and river delta region, searching for signs of ancient microbial life (NASA Press Release 02-8-2021).

The Perseverance Rover is equipped with a payload of sophisticated instrument suites, together with an Advanced Sample Collection System. The instrumentation suites include:

• The MarsEntry, Descent, and Landing Instrumentation 2 (MEDLI2) sensor suite, which collected data on the atmosphere, during entry.
• The Terrain-Relative Navigation system, which guided the engine during its descent.
• The  Mastcam-Z, two zoomable science cameras on Perseverance’s remote sensing mast, designed to create high-resolution panoramas of the Martian landscape.
• The SuperCam, using a pulsed laser to study the chemistry of rocks and sediment, also equipped with its own microphone.
• The Planetary Instrument for X-ray Lithochemistry (PIXL) used in  conjunction with Sherloc (below) to analyze the elementary composition of Martian rock samples 
• The Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC) instrument suite on board is designed to detect minerals and molecules in the search for ancient life.
• The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), designed to manufacture oxygen out of Mars thin air.
• The Mars Environmental Dynamics Analyzer (MEDA) instrument, with sensors on the mast and body of the Rover, is designed to provide key info on Mars weather, dust and climate.
• The Radar Imager for Mars’ Subsurface Experiment (RIMFAX), designed to collect data to determine how the layers of soil on Mars stack up.
• The Mars Ingenuity Helicopter,  currently charging on the engine’s belly.  

 On February 22, 2021, NASA released an edited version (included below) of the extraordinarily clear, hi-definition color video footage, of the vehicle’s Entry, Descent, and Landing (EDL). The 3-minute NASA Youtube video shows the deployment of the parachute in a bottom-up view from under the parachute, separation of the heat shield covering the spacecraft,  and the slow retro-rocket propelled descent guided by the descent stage, all the way to touchdown on Martian soil, in a top-down view. The Official NASA edited footage is amazingly clear, considering the distance. In comparison with previous mission footage from planet Mars, which used to be colored in the editing room, the Perseverance Rover mission footage is the first hi-definition full-color footage streamed from the Red planet.  Indeed the images are stunningly clear. (NASA Press release, 02-22-2021)

The EDL video cam system functioned upon entry into the Martian atmosphere, starting at about 7 miles (11 km) above the surface of Mars. One camera, on top of the backshell, protecting the Rover, was looking up at the parachute. One camera on the retrorocket decent stage was looking down. Two cameras were on the Rover: one camera was looking up at the descent stage, and one camera was looking down at Martian soil, once the heatshield had separated. The image  included (to the right) illustrates the Mars 2020 entry, descent and landing camera suite with camera position, respectively on the backshell, descent stage and Rover.

Perseverance Rover’s Descent and Touchdown on Mars (Official NASA Video)

https://youtu.be/4czjS9h4Fpg  (released 22 -02-2021)

While the EDL camera suite was designed to give viewers multiple views of the EDL, it is perhaps much more difficult to fathom is the actual violence of the supersonic parachute deployment, that scientists report. The Perseverance Rover was traveling at approximately 12,500 mph (20,100 kph) upon entering the upper Mars atmosphere. Approximately 230 seconds later the parachute deployed almost instantaneously (in 1 second) from a compressed 18 x 26 inch (46 x 66 cm) cylinder, into a fully inflated 70.5 foot-wide (21.5 meter-wide) canopy, generating tens of thousands of pounds of force to slow the Rover’s speed. During the NASA press conference, presenting the EDL footage, NASA scientists noted that the parachute deployed with no tangled strings, which is amazing since the deployment happened in just 1 second, at supersonic speed (i.e.; at a speed exceeding the speed of sound). 

Stay tuned for more! The Perseverance Rover is powered by a Multi-Mission Radioisotope Thermoelectric Generator, or MMRTG, provided by the Department of Energy in partnership with NASA.  Safe landing on Mars is only the beginning of the Mars Perserverance mission, and all the discoveries it promises to offer.

References

Press Release  21-021 (Feb. 22, 2021) NASA’s Mars Perseverance Rover provides front-row seat to landing, first audio recording of red planet.   https://www.nasa.gov/press-release/nasa-s-mars-perseverance-rover-provides-front-row-seat-to-landing-first-audio

Press Release 21-018 (Feb. 18, 2021) Touchdown! NASA's Mars Perseverance Rover Safely Lands on Red Planet.  https://www.nasa.gov/press-release/touchdown-nasas-mars-perseverance-rover-safely-lands-on-red-planet

NASA – Entry Descent and Landing (EDL).   https://mars.nasa.gov/mars2020/timeline/landing/entry-descent-landing/#Terrain-Relative-Navigation

Simulated EDL https://youtu.be/tITni_HY1Bk

The Cameras on the Mars 2020 Perseverance Rover. https://mars.nasa.gov/mars2020/spacecraft/rover/cameras/

NASA - Power and thermal systems (MMRTG).   https://rps.nasa.gov/power-and-thermal-systems/power-systems/

NASA – The Extraordinary Sample-Gathering System of NASA's Perseverance Mars Rover.   https://www.jpl.nasa.gov/news/the-extraordinary-sample-gathering-system-of-nasas-perseverance-mars-rover

Barnett, A (Oct. 8, 2020) NASA's Perseverance Rover Will Peer Beneath Mars' Surface (RIMFAX).  https://www.jpl.nasa.gov/news/nasas-perseverance-rover-will-peer-beneath-mars-surface

NASA (May 26,2020)- The Detective aboard  NASA’s Perseverance Rover (SHERLOC).   https://www.jpl.nasa.gov/news/the-detective-aboard-nasas-perseverance-rover

NASA (May 1, 2020) -  NASA’s Perseverance Rover will look at Mars through these eyes  (MastCamX).   https://mars.nasa.gov/news/8663/nasas-perseverance-rover-will-look-at-mars-through-these-eyes/

NASA (Sept. 22, 2020) - NASA's New Mars Rover Will Use X-Rays to Hunt Fossils (PIXL).   https://www.jpl.nasa.gov/news/nasas-new-mars-rover-will-use-x-rays-to-hunt-fossils

NASA  - MOXIE  https://mars.nasa.gov/mars2020/spacecraft/instruments/moxie/

NASA – MEDA  https://mars.nasa.gov/mars2020/spacecraft/instruments/meda/

NASA – Moxie for scientists.   https://mars.nasa.gov/mars2020/spacecraft/instruments/moxie/for-scientists/

NASA (April 29, 2020) - Ingenuity Mars Helicopter.  https://www.youtube.com/watch?v=0RQWv1ybsjM

NASA (Jan 27, 2021) -   NASA’s Perseverance 22 days from landing.   https://www.nasa.gov/feature/jpl/nasa-s-perseverance-rover-22-days-from-mars-landing