“About 3.9 billion years ago, a wayward rock slammed into Mars, punching a 45-kilometre-wide hole into its surface. On 18 February, NASA plans to land its latest rover inside that pit, named Jezero Crater.
“The goal is to explore an area of Mars that was once much warmer and wetter, and perhaps even liveable. Scattered throughout the crater are geological formations hinting at its watery past, including the remains of a lake and a river delta. Studying the make-up of these rocks – in a region where no spacecraft has gone before – will give NASA its best chance yet at answering the age-old question of whether life ever existed on Mars.”
– Alexandra Witze, contributing correspondent for Nature and Science News magazines
What an extraordinary day – February 18, 2021. This day marks the landing of the most ambitious Mars mission yet.
“Mars captivates our imagination and has been part of our dreams for many decades, and Perseverance balances on the long history of systematic science driven exploration of Mars,” Dr. Thomas Zurbuchen, NASA’s associate administrator of the science mission directorate, said in a briefing ahead of the landing.
(Michael Sheetz. “Watch NASA attempt to land rover Perseverance on Mars.” NBC News. February 18, 2021.)
“Perseverance” aims to become the first rover to land since 2012, when NASA’s Curiosity spacecraft arrived in Gale Crater, a dry lake bed about 3,700 kilometres from Jezero. The mission also includes a helicopter drone called “Ingenuity” that will scout ahead, looking for intriguing targets to study.
The rover has two ways of gathering rock samples. It can either analyse them with its on-board laboratory or it can save them for return to Earth by future missions. The advantage of such an approach is that the rocks can be studied in more detail by a wider variety of instruments.
Plans for 2026, include a “fetch rover” to be deployed to the planet to collect the caches and deliver them to a rocket stationed on the Martian surface. The rocket will launch into orbit around the planet, where another orbiter will collect the samples and return them to Earth.
The landing site is so very important. “This region is a very old part of Mars,” says Vivian Sun, a planetary geologist at the Jet Propulsion Laboratory in Pasadena, California, and a member of the Perseverance science team. “That’s important because the oldest periods of time are when we think Mars was most habitable.”
Images taken by orbiting spacecraft show that one river that formed during this time flowed through and over the western edge of Jezero Crater. The river must have carried tiny particles of sediment scoured from far upstream. When it entered the crater, it dropped this sediment into the lake there, creating a delta that fanned out to the east. In and around the delta and lake, conditions would have been ripe for microbial life to thrive. Later, the lake drained away and left behind the formation, now turned to rock.
(Alexandra Witze. “The hunt for life on Mars: A visual guide to NASA’s latest mission.” Nature.com. February 16, 2021.)
Jezero crater as it may have appeared 3.5 billion years ago, when Mars was warm and wet.. NASA/JPL-Caltech
The Stuff of Science Fiction
Previous Mars missions including Curiosity and Opportunity have suggested Mars was once a wet planet with an environment likely to have been potentially supportive of life billions of years ago. Astrobiologists hope this latest mission can offer some evidence to prove whether that was the case.
Colin Wilson, a physicist at Oxford University, says …
“Of all the steps needed to develop life, how many occurred on Mars? This [mission] tells us not only about whether we’re alone in the solar system but also about how likely we are to find life in the thousands of other planets being discovered around other suns – so [it] has truly cosmic implications.”
(Natalie Grover. “Nasa Perseverance rover to land on Mars in search of life.” The Guardian. February 18, 2021.)
Imagine. This mission may set the scientific world ablaze with its new discoveries.
Susanne Schwenzer, an astrobiologist at the Open University, posits …
“If indications of life were discovered on Mars” – and there was a huge responsibility on scientists to be sure – “it would be the most exciting finding since the insight that the Earth is not flat.”
Samantha Rolfe, Lecturer in Astrobiology and Principal Technical Officer at Bayfordbury Observatory, says …
“If we find even a hint of evidence for life, the next steps will be to detect it with multiple analytical techniques, show that it isn’t contamination from Earth and work out whether the evidence make sense in the context of the environment and data from the other instruments.”
That means any evidence for life will have to go through the rigorous scientific process of testing, re-testing and peer review. What’s more, Perseverance is only conducting analysis in one crater on Mars. If there is any current life on Mars, we might be more likely to find it deeper below the surface, which is constantly bombarded with harmful radiation.
(Samantha Rolfe. “Perseverance Mars rover: how to prove whether there’s life on the red planet.” The Conversation. February 16, 2021.)
NASA announced in October 2020 that water has been confirmed to be present on some sunlight surfaces of the moon, according to two studies published in the journal Nature Astronomy. What new finds will the Perseverance mission add to our knowledge of Mars?
NASA has been developing new landing techniques and technologies that will facilitate what scientists hope will be a successful landing.
“It’s truly exciting how our technologies have matured, bringing us to the point where we can attempt this amazing feat,” said Lori Glaze, Nasa’s director of planetary science.
NASA’s stated goal is to put astronauts on Mars sometime in the 2030s.
Mars has long exerted a powerful hold on the imagination but has proved to be the graveyard for numerous missions. Spacecraft have blown up, burned up or crash-landed, with the casualty rate over the decades exceeding 50%. China’s last attempt, in collaboration with Russia in 2011, ended in failure.
Only the United States has successfully put a spacecraft on Mars, doing it eight times, beginning with the twin Vikings in 1976. Two NASA landers are now operating there, InSight and Curiosity. Six other spacecraft are exploring the planet from orbit: three U.S., two European and one from India.
(Marcia Dunn. “Mars About to Be Invaded by Earthlings.” Associated Press. July 13, 2020.)
Two space missions from China and the United Arab Emirates (UAE), respectively, are set to reach Mars. The UAE’s Hope mission went into orbit around Mars on February 9. On February 15, the Chinese Tianwen-1 mission – an orbiter and lander – swung into polar orbit, with a predicted landing date sometime in May.
The specific character of the so-called Space Age 2.0, which, compared to the first one, looks more diverse, and where non-US actors, public and private, feature prominently, especially Asian ones. The missions also symbolize an emerging space race between the two superpowers – the United States and China – and over which country gets the vast sociopolitical clout of having put the first boots on Mars.
“Mars has moved into the symbolic role of demonstrating the superiority of technology,” Flinders University space archaeologist Alice Gorman told Bloomberg.
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