NASA’s Perseverance Rover Mission: Unbelievable!

 Copyright © Françoise Herrmann

 The perfectly planned, and so far, flawlessly executed 2020, NASA-led, Perseverance Rover, robotic explorer mission to Mars, stands on the shoulders of many giants that dared to stumble. In other words, nothing quite compares to the treat that NASA offered to the world, on Feb 18th, 2021. Since 1960, when the first Soviet Marsnik1 probe was launched, and failed to reach Earth orbit, many essentially Soviet and US-led missions, as well as Japanese, Indian, European Space Agency, Chinese, and most recently United Arab Emirate (UAE) missions, have been launched (NASA TimeLine; NASA Chronology). Mars exploration missions, such as deep space probes, orbiters mapping the Martian environment, landers on Martian soil, rovers, robotic explorers, and the latest hybrid aircraft-spacecraft Ingenuity, many of which failed. Missions that failed to launch, to orbit, to detach, to enter the Martian atmosphere, to communicate with Earth, or otherwise that missed their targets. Fortunately, however, the missions failed not without significantly informing both the theory and practice of space exploration, and its connected domains in engineering, physics, chemistry, astronomy, robotics, informatics, plus more.

Perhaps then, in light of an international time-line history of Mars exploration fraught with failures, that the name "Perseverance" of the 2020 mission Rover, acquires higher significance, next to all the hurdles of the COVID-19 pandemic (NASA Chronology). In any event, it certainly explains the NASA scientists’ disappointment-defense mantra: “We get what we get and we don’t get upset.."(NASA Press Conference Feb. 22, 2021) A mantra that perhaps also uncovers the true vulnerability of working with such data magnitude, scale and complexity, considering after all, that the 2020 mission finally worked “to an unbelievably perfect T”, with footage so awesome that many folks find it truly hard to walk away from their viewing screens.

Actually, Mars is a very solicited planet in 2021. Aside from the US NASA Perseverance Rover mission, together with the Ingenuity aircraft tucked inside its belly, several spacecraft are already orbiting, or exploring Mars (NASA Perseverance). Specifically, the US rovers Curiosity and Insight continue to operate on Mars, and six orbiters (three US, two European and one Indian) are observing Mars (Associated Press, 2020; NASA Insight; NASA Curiosity). 

Additionally, no less than two new Mars exploration missions were also launched, at about the same time as the US Perseverance Rover mission on July 30th, 2020. The United Arab Emirates (UAE) orbiter mission called Amal (“Hope” in Arabic) was launched on July 15th, 2020, from the Tanegashima Space Center, in Japan. The Amal orbiter mission, controlled in Dubai, is designed to monitor global Martian weather (Barrett, A., 2020). Whereas, the China-led Probe, first-of-its-kind-combination orbiter-lander-rover mission, designated “Tianwen” (Questions for Heaven in Chinese), was launched on July 23rd, 2020, from the Wenchang Spacecraft Launch Site in Hainan, China. The Chinese probe successfully started orbiting Mars on February 10th, 2021, with a perigee of about 400 kilometers, and a circling period of 10 days. The Chinese lander, together with its rover payload, will detach from the orbiter some time in May or June 2021, for entry into the Martian Atmosphere. The anticipated touchdown site is the Utopia Planitia Crater. The lander will unfurl a ramp, for the still un-named Chinese rover to roll out, and begin exploration (Stein, 2020).

All three missions, the US Perseverance robotic explorer, the UAE Amal Probe orbiter, and the China TianWen  Probe, combination orbiter-lander-rover,  launched in the summer 2020, were taking advantage of a favorable alignment of Earth and Mars, which only occurs every 26 months (Associated Press, 2020; Child, 2020; Lemonick, 2019).  An alignment, which essentially makes the travel time shorter, and entry into the Martian atmosphere easier.

Before safely touching down on Mars, exactly as planned, on February 18th, 2021, the NASA Perseverance Rover, together with the Ingenuity aircraft tucked beneath it, survived an imagination-defying, 300-million mile journey. A perilous journey, beginning with takeoff from Cape Canaveral Air Force Station, in Florida, inside a spacecraft capsule, onboard an Atlas C-451 rocket (NASA - Launch). Takeoff was shortly followed by separation of the capsule from the rocket, and a 7-month solar-powered cruise through space, at a speed of approx. 26,900 mph (NASA - Cruise). A cruise culminating in the most intense part of the journey, consisting in the 7-minute, scorching temperature, 9G vibration Entry into the Martian atmosphere, Descent and Landing of the spacecraft on Martian soil (NASA - Landing; EDL phase). An EDL phase that included such critical maneuvers as cruise stage separation, Martian atmospheric entry at 12,500 mph, with a dramatic heat peak measured at 2370 degrees Fahrenheit (1300 degrees Celsius) caused by massive speed desceleration to 1000 mph, using Martian atmosphere, followed by parachute deployment, separation of the heat shield and aeroshell protection, firing of the descent stage retro-rockets, and separation from the descent stage to touchdown (see image below), most of which was captured on video camera, in otherwise unbelievable, mesmerizing clarity (NASA JPL - Simulated EDL video; NASA (non-simulated) Video - Descent & Touchdown).

  The below image shows a (non-simulated) top-down view, taken from the retro-rocket powered descent stage. The top-down view shows the Perseverance Rover being lowered onto Martian soil, using bridles, for touchdown exactly on the Jezero Crater, some 300 million miles away. The umbilical cord also visible is the data cable, sending information back and forth to the descent stage, including captured video data, from which this still was extracted.

Reference

Associated Press (July 13, 2020) Missions to Mars: U.S., Mars: U.S., China, UAE prepare to send spacecraft to the red planet  https://www.latimes.com/world-nation/story/2020-07-13/us-china-uae-send-spacecraft-to-mars

Barrett, A. (July 20, 2020) UAS Mars mission 'Hope Probe' launches successfully.   https://www.sciencefocus.com/news/uae-mars-mission-hope-probe-launches-successfully/

Child, D. (Feb. 02-2021) Space race: UAE, US and Chinese missions prepare to explore Mars https://www.aljazeera.com/economy/2021/2/8/space-race-uae-us-and-chinese-missions-prepare-to-explore-mars

Lemonick, S. (Juy 21, 2019) Three rovers will head to mars in 2020. Here’s what you need to know about their chemical missions. Astrochemisty Society.   https://cen.acs.org/physical-chemistry/astrochemistry/3-rovers-head-Mars-2020/97/i2 9 

NASA Mars Exploration time line (1964 - 2016)  https://mars.nasa.gov/mars-exploration/timeline/

NASA History Division - A chronology of Mars exploration (1960 – 2016)   https://history.nasa.gov/marschro.htm

NASA - Mars 2020 Perseverance Rover Mission Overview   https://mars.nasa.gov/mars2020/mission/overview/

NASA - Mars 2020 Perseverance Rover Mission Launch  https://mars.nasa.gov/mars2020/timeline/launch/

NASA - Mars 2020 Perseverance Rover Mission Cruise   https://mars.nasa.gov/mars2020/timeline/cruise/

NASA - Mars 2020 Perseverance Rover Mission Landing   https://mars.nasa.gov/mars2020/timeline/landing/

NASA – MARS Entry, Descent and Landing   https://mars.nasa.gov/mars2020/timeline/landing/entry-descent-landing/

NASA JPL Video Simulation - Perseverance's Entry Descent and Landing   https://youtu.be/M4tdMR5HLtg

NASA - Mars Curiosity Rover  https://mars.nasa.gov/msl/home/

NASA – Mars Insight Mission   https://mars.nasa.gov/insight/

NASA - 6 things to know about NASA's Mars Ingenuity helicopter    https://www.nasa.gov/feature/jpl/6-things-to-know-about-nasas-ingenuity-mars-helicopter

NASA (April 3, 2020) NASA's Perseverance Mars Rover Gets Its Wheels and Air Brakes  https://www.nasa.gov/feature/nasas-perseverance-mars-rover-gets-its-wheels-and-air-brakes

NASA – Press Conference Transacript – Febraury 22, 2021 Perseverance Rover searches for life on Mars.  https://www.rev.com/blog/transcripts/nasa-press-conference-transcript-february-22-perseverance-rover-searches-for-life-on-mars

NASA Video (non-simulated) - Perseverance descent and touchdown    https://youtu.be/4czjS9h4Fpg

NASA reinventing the wheel   https://www.nasa.gov/specials/wheels/

NASA Perseverance Rover Wheels (specs)  https://mars.nasa.gov/mars2020/spacecraft/rover/wheels/

Stein, V. (Feb. 7, 2020)Tianwen-1: China's first Mars mission   https://www.space.com/tianwen-1.html#:~:text=Tianwen%2D1%20is%20China's%20first,of%20the%20COVID%2D19%20pandemic