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Nasa’s perseverance rover finds its first possible hint of ancient life on mars.

The discovery builds the case for bringing pieces of Mars back to Earth for future study

Perseverance examined this Mars rock on July 21. The leopard spot–like features speckling the clay-colored part of the rock resemble structures in Earth rocks that are associated with life.

MSSS/JPL-Caltech/NASA

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By Lisa Grossman

July 25, 2024 at 7:52 pm

NASA’s Perseverance rover has bagged its first hint of ancient microbes on Mars.

“We’re not able to say that this is a sign of life,” says Perseverance deputy project scientist Katie Stack Morgan of NASA’s Jet Propulsion Lab in Pasadena, Calif.  “But this is the most compelling sample we’ve found yet.”

The rover drilled up the sample on July 21 from a reddish rock, dubbed Cheyava Falls after a feature at the Grand Canyon. It is the first piece of Mars that Perseverance has examined that contains organic molecules, the building blocks of life, project scientist Ken Farley of Caltech reported July 25 at the 10th International Conference on Mars in Pasadena.

This isn’t the first sign of organics on Mars — the Curiosity rover detected organic molecules in a region called Gale Crater in 2014 (SN: 12/16/14) . But scientists have struggled to identify organics since Perseverance landed in an ancient dried-up lake called Jezero Crater in 2021 , says Stack Morgan ( SN: 2/17/21 ).

Adding to the excitement, the reddish rock is speckled with little white spots with black rims. “They look like a tricolored leopard spot,” Stack Morgan says.

Perseverance examined the spots with instruments that can identify their chemical contents and found that the rims contain iron phosphate molecules. On Earth, rings with similar texture and chemistry are associated with ancient microbial life . The chemical reactions that create the rings can be an energy source for microbes.

“They don’t require life, of course, and that’s an important caveat,” Stack Morgan says. “But based on our experience with similar things on Earth, there is a possibility that life could have been involved, and these could have a biological origin.”

The rock has other confusing features that muddy the picture of how it formed, Stack Morgan says. It is shot through with white veins of calcium sulfate. These veins are filled with millimeter-sized crystals of olivine, a mineral that forms from magma. The inclusion of both the spots and these volcanic features in the same rock is “a little bit mysterious,” Stack Morgan says, as they point to different origins. Figuring out how the rock formed could help tell how likely it is to have had the right conditions and temperatures to host biology.

Planetary scientist Paul Byrne thinks we should be circumspect about the finding.

“Could this truly be a biosignature? Yes. And if it is, then it really is the kind of society-altering discovery that the discovery of truly extraterrestrial life would be,” says Byrne, of Washington University in St. Louis. But it’s also possible that the spots came from something other than life, “in which case all this is is an interesting example of water-rock chemistry.”

The only way to find out for sure is to bring the rock home. A big part of Perseverance’s mission is to collect samples from interesting rocks for a future spacecraft to return to Earth, where they can be studied in more sophisticated laboratories than a rover can carry on its back. Perseverance has thrown everything it has at this rock already, Stack Morgan says.

But funding uncertainty has recently put the program, known as Mars Sample Return, on hold (SN: 5/8/24).

“With this sample, the rationale for MSR is strengthened even more, and should I hope motivate NASA to commit to pulling off this project sooner rather than later,” Byrne says.

Stack Morgan says the rover team is carrying on despite the budget uncertainty.

“We have a mission to carry out, and a job to do: collecting compelling samples,” Stack Morgan says. “It can only be our hope that the samples that we collect are compelling enough to justify the cost of Mars Sample Return. I think with this exciting sample, that really hits that home.”

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Why we explore Mars—and what decades of missions have revealed

In the 1960s, humans set out to discover what the red planet has to teach us. Now, NASA is hoping to land the first humans on Mars by the 2030s.

Mars has captivated humans since we first set eyes on it as a star-like object in the night sky. Early on, its reddish hue set the planet apart from its shimmering siblings, each compelling in its own way, but none other tracing a ruddy arc through Earth’s heavens. Then, in the late 1800s, telescopes first revealed a surface full of intriguing features—patterns and landforms that scientists at first wrongly ascribed to a bustling Martian civilization. Now, we know there are no artificial constructions on Mars. But we’ve also learned that, until 3.5 billion years ago, the dry, toxic planet we see today might have once been as habitable as Earth.

Since the 1960s, humans have set out to discover what Mars can teach us about how planets grow and evolve, and whether it has ever hosted alien life. So far, only uncrewed spacecraft have made the trip to the red planet, but that could soon change. NASA is hoping to land the first humans on Mars by the 2030s—and several new missions are launching before then to push exploration forward. Here’s a look at why these journeys are so important—and what humans have learned about Mars through decades of exploration.

Why explore Mars

Over the last century, everything we’ve learned about Mars suggests that the planet was once quite capable of hosting ecosystems—and that it might still be an incubator for microbial life today.

Mars is the fourth rock from the sun, just after Earth. It is just a smidge more than half of Earth’s size , with gravity only 38 percent that of Earth’s. It takes longer than Earth to complete a full orbit around the sun—but it rotates around its axis at roughly the same speed. That’s why one year on Mars lasts for 687 Earth days , while a day on Mars is just 40 minutes longer than on Earth.

Despite its smaller size, the planet’s land area is also roughly equivalent to the surface area of Earth’s continents —meaning that, at least in theory, Mars has the same amount of habitable real estate. Unfortunately, the planet is now wrapped in a thin carbon dioxide atmosphere and cannot support earthly life-forms. Methane gas also periodically appears in the atmosphere of this desiccated world, and the soil contains compounds that would be toxic to life as we know it. Although water does exist on Mars, it’s locked into the planet’s icy polar caps and buried, perhaps in abundance, beneath the Martian surface .

Today, when scientists scrutinize the Martian surface, they see features that are unquestionably the work of ancient, flowing liquids : branching streams, river valleys, basins, and deltas. Those observations suggest that the planet may have once had a vast ocean covering its northern hemisphere. Elsewhere, rainstorms soaked the landscape, lakes pooled, and rivers gushed, carving troughs into the terrain. It was also likely wrapped in a thick atmosphere capable of maintaining liquid water at Martian temperatures and pressures.

Somewhere during Martian evolution, the planet went through a dramatic transformation, and a world that was once rather Earthlike became the dusty, dry husk we see today. The question now is, what happened? Where did those liquids go, and what happened to the Martian atmosphere ?

Exploring Mars helps scientists learn about momentous shifts in climate that can fundamentally alter planets. It also lets us look for biosignatures, signs that might reveal whether life was abundant in the planet’s past—and if it still exists on Mars today. And, the more we learn about Mars, the better equipped we’ll be to try to make a living there, someday in the future.

Past missions, major discoveries

Since the 1960s, humans have sent dozens of spacecraft to study Mars . Early missions were flybys, with spacecraft furiously snapping photos as they zoomed past. Later, probes pulled into orbit around Mars; more recently, landers and rovers have touched down on the surface.

But sending a spacecraft to Mars is hard , and landing on the planet is even harder. The thin Martian atmosphere makes descent tricky, and more than 60 percent of landing attempts have failed. So far, four space agencies—NASA, Russia’s Roscosmos, the European Space Agency (ESA), and the Indian Space Research Organization (ISRO)—have put spacecraft in Martian orbit. With eight successful landings, the United States is the only country that has operated a craft on the planet’s surface. The United Arab Emirates and China might join that club if their recently launched Hope and Tianwen-1 missions reach the red planet safely in February 2021.

Early highlights of Mars missions include NASA's Mariner 4 spacecraft , which swung by Mars in July 1965 and captured the first close-up images of this foreign world. In 1971, the Soviet space program sent the first spacecraft into Martian orbit. Called Mars 3 , it returned roughly eight months of observations about the planet's topography, atmosphere, weather, and geology. The mission also sent a lander to the surface, but it returned data for only about 20 seconds before going quiet.

Over the subsequent decades, orbiters returned far more detailed data on the planet's atmosphere and surface, and finally dispelled the notion, widely held by scientists since the late 1800s, that Martian canals were built by an alien civilization. They also revealed some truly dramatic features: the small world boasts the largest volcanoes in the solar system, and one of the largest canyons yet discovered—a chasm as long as the continental United States. Dust storms regularly sweep over its plains, and winds whip up localized dust devils.

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In 1976, NASA’s Viking 1 and 2 became the first spacecraft to successfully operate on the planet’s surface, returning photos until 1982. They also conducted biological experiments on Martian soil that were designed to uncover signs of life in space—but their results were inconclusive , and scientists still disagree over how to interpret the data.

NASA’s Mars Pathfinder mission , launched in 1996, put the first free-moving rover—called Sojourner—on the planet. Its successors include the rovers Spirit and Opportunity , which explored the planet for far longer than expected and returned more than 100,000 images before dust storms obliterated their solar panels in the 2010s.

Now, two NASA spacecraft are active on the Martian surface: InSight is probing the planet’s interior and it has already revealed that “ marsquakes” routinely rattle its surface . The Curiosity rover , launched in 2012, is also still wheeling around in Gale Crater, taking otherworldly selfies, and studying the rocks and sediments deposited in the crater’s ancient lakebed.

Several spacecraft are transmitting data from orbit: NASA’s MAVEN orbiter , Mars Reconnaissance Orbiter , and Mars Odyssey ; ESA’s Mars Express and Trace Gas Orbiter ; and India’s Mars Orbiter Mission .

Together, these missions have shown scientists that Mars is an active planet that is rich in the ingredients needed for life as we know it—water, organic carbon , and an energy source. Now, the question is: Did life ever evolve on Mars , and is it still around?

Future of Mars exploration

Once every 26 months , Earth and Mars are aligned in a way that minimizes travel times and expense , enabling spacecraft to make the interplanetary journey in roughly half a year. Earth’s space agencies tend to launch probes during these conjunctions, the most recent of which happens in the summer of 2020. Three countries are sending spacecraft to Mars during this window: The United Arab Emirates, which launched its Hope spacecraft on July 20 and will orbit Mars to study its atmosphere and weather patterns; China, which launched its Tianwen-1 on July 23 , and the United States, currently targeting July 30 for the launch of its Perseverance rover .

Perseverance is a large, six-wheeled rover equipped with a suite of sophisticated instruments. Its target is Jezero Crater, site of an ancient river delta , and a likely location for ancient life-forms to have thrived. Once on the surface, Perseverance will study Martian climate and weather, test technologies that could help humans survive on Mars, and collect samples from dozens of rocks that will eventually be brought to Earth. Among its goals is helping to determine whether Mars was—or is—inhabited, making it a true life-finding Mars mission.

All of the robotic activity is, of course, laying the groundwork for sending humans to the next world over. NASA is targeting the 2030s as a reasonable timeframe for setting the first boots on Mars, and is developing a space capsule, Orion , that will be able to ferry humans to the moon and beyond.

Private spaceflight companies such as SpaceX are also getting into the Mars game. SpaceX CEO Elon Musk has repeatedly said that humanity must become “ a multiplanetary species ” if we are to survive, and he is working on a plan that could see a million people living on Mars before the end of this century.

Soon, in one way or another, humanity may finally know whether our neighboring planet ever hosted life—and whether there’s a future for our species on another world.

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April 5, 2023

NASA’s Perseverance Rover May Already Have Evidence of Ancient Martian Life

A half-kilogram’s worth of samples gathered by NASA’s Perseverance rover for eventual return to Earth holds weighty implications for life on Mars

By Jonathan O'Callaghan

NASA’s Perseverance Mars rover took a selfie with several of the 10 sample tubes it deposited at a sample depot it is creating within an area of Jezero Crater nicknamed Three Forks.

NASA/JPL-Caltech/MSSS

If life ever existed on Mars, we may already have the answer at hand. In January NASA’s Perseverance rover deposited 10 tubes on the surface of Mars. Each contains a sample of Martian rock that was carefully selected for its potential to clarify chapters of the planet’s still-murky history. Those tubes “are capable of telling us whether Mars was habitable,” says Mitch Schulte, Perseverance’s program scientist at NASA Headquarters in Washington, D.C. “We see evidence of particular minerals that tell us there was water. Some of these minerals indicate there was organic material.”

But to know for sure, scientists need to bring these tubes back to Earth for closer study—an audacious endeavor known as Mars Sample Return (MSR), which is slated for the early 2030s via a follow-up robotic mission . These 10 tubes are only the opening course in a bigger awaiting feast, a backup cache in case Perseverance breaks down before it can fill and deliver the 33 additional tubes that it carries. These tubes will hold samples sourced from the area in and around Jezero Crater, the site of a four-billion-year-old river delta and the locale where the rover landed on February 18, 2021. Although many of the samples are yet to be gathered for a journey to Earth that remains years in the future, those already collected have whetted researchers’ appetite for their return home.

Scientists targeted Jezero for Perseverance because, on our planet, sprawling river systems like that found in the Martian crater build up enormous deposits of sediments. Washed in from a sizable swath of the surrounding landscape, these deposits contain various minerals that can be used to chart the Red Planet’s past geology. Also most anywhere water is found on Earth, life accompanies it. The same might hold true for Mars, meaning Jezero’s sediments could conceivably harbor biological remains. “We’re looking for signs of habitability—liquid water and the raw materials of life,” says Mark Sephton of Imperial College London, a member of the rover’s sampling team.

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A close-up of one of the Perseverance Mars rover’s 43 sample tubes, deposited for future retrieval on the surface of Mars. Credit: NASA/JPL-Caltech/MSSS

Perseverance collects most of its samples using a small drill, producing chalk-stick-sized specimens that each fit within cigarlike tubes measuring less than 15 centimeters long. Of the 43 sample tubes, 38 are slated for samples from the surface, with the remaining five being “witness tubes” to catch whiffs of Martian air and check for any contaminating gases that might vent from the rover. Collected in September 2021 , the rover’s first sample is thought to be igneous rock from an ancient lava flow. Studying this material should allow scientists to date the crater more precisely. Since then, the rover has filled nearly half of its remaining tubes as it journeys several kilometers further up the ancient river’s channels toward Jezero Crater’s rim.

As a contingency, 10 of the samples are duplicates, each paired with another sample taken from the same location. These are the tubes Perseverance dropped on the surface as backup for potential future retrieval. In December 2022, in one of the last decisions he’d make at the space agency before reentering the private sector, NASA’s then science chief Thomas Zurbuchen made the call to drop that cache at a location called Three Forks. The surface drop-off was completed at the end of January, around the same time Perseverance officially began the “extended” phase of its mission—and after the science team agreed that those 10 samples alone could answer the question of past habitability if needed. MSR’s optimal plan calls for the rover to carry its remaining tubes to a yet-to-be-built lander slated to touch down in Jezero’s vicinity around 2030. Once the lander has secured those samples, it will launch them on a rocket back to Earth .

“We want the ones on the rover to come back,” Zurbuchen says. “But even the ones on the surface check all the boxes.” That includes igneous rock to date the crater and sedimentary rock and clays that may contain biosignatures, perhaps even fossilized evidence of microbial life. “They’re already worth the $10-billion investment,” Zurbuchen says, citing the MSR program’s estimated total cost. Some of the most promising samples are from a location called Wildcat Ridge, a meter-wide rock that contains evidence of sulfates. “Those are the ones we’re most excited about in terms of potential biosignatures,” says Kathleen Benison of West Virginia University, who is part of Perseverance’s sampling team. “Sulfate minerals can grow from groundwater. On Earth, those kinds of waters tend to have a lot of microbial life,” which can be entombed and preserved in sulfate minerals.

Besides sulfates, life-seeking scientists are particularly eager to grab samples from mudstones—fine-grained sedimentary rocks that the Curiosity rover has seen in Gale Crater but that Perseverance has not yet spotted. “Microbe cells are tiny,” says Tanja Bosak of the Massachusetts Institute of Technology, who is also part of the sampling team. “The mineral grain size should be even finer to preserve the [fossil] shape instead of destroying it. If you roll a boulder over a person, you will smush that person into something unrecognizable. For a microbe, everything is a boulder—unless you’re talking about mudstones.” The team members are also keen to sample carbonates, similar to things like chalk and limestone on Earth, which could preserve biosignatures as well. “If there had been microbial life in the lake, [the carbonates] could have trapped microbial matter in it,” says Sanjeev Gupta of Imperial College London, who is one of the “long-term planners” who plot out the rover’s path. On March 30, Perseverance collected its first carbonate sample, from a rock named “Berea” thought to have formed from material washed into Jezero by the ancient river.

Taken on March 30, 2023, this image shows the rocky outcrop the Perseverance science team calls “Berea” after the NASA Mars rover extracted a carbonate rock core ( right ) and abraded a circular patch ( left ). Credit: NASA/JPL-Caltech

While Perseverance has been hard at work collecting samples on Mars, the return phase of the mission remains in flux. Originally, NASA had planned for a European-built “fetch” rover to land on Mars around 2030, collect the samples from Perseverance and return them to a capsule on the lander for launch. Once in orbit, the sample capsule would rendezvous with a European orbiter, which would ferry the samples back to Earth for a landing in 2033. These plans were complicated, however, by Russia’s invasion of Ukraine in 2022. In response to Russia’s aggression, European Space Agency (ESA) officials chose to step back from a partnership with the nation on another long-simmering Mars mission, the Rosalind Franklin ExoMars rover. Russia had been due to provide the rover’s nuclear power source, as well as the launch vehicle and landing platform. NASA has now agreed to supply such missing pieces and has sought funding to do so in its budgetary request to Congress last month. But this unanticipated assistance comes at the cost of the fetch rover. “We couldn’t do both,” Zurbuchen says. “We could not individually land the fetch rover and do ExoMars.”

The ExoMars mission, most everyone agrees, is eminently worth saving. The Rosalind Franklin rover will carry a drill that can augur two meters beneath the Martian surface, accessing a subterranean habitat for past and present life that is considerably less hostile than the surface. “Nobody has ever done that on Mars,” Zurbuchen says. “Our science community thinks it’s really important.”

Jorge Vago, ESA’s ExoMars project scientist in the Netherlands, was glad that NASA stepped in. To hit a target launch date of 2028, set forth by European member states in order to save the mission, “we need the American contributions,” Vago says. “It’s an amazing mission. If we find super interesting stuff that’s suggestive of a possible biological origin, I would expect we may want to have another sample return mission and bring back samples from the subsurface.”

NASA’s current MSR plan faces its own challenges. In a mid-March town hall hosted by NASA’s Science Mission Directorate, Jeff Gramling, MSR program director at NASA Headquarters, said that some aspects of the mission may need to be “descoped.” This would be a preventative measure to keep budgets under control. NASA’s annual request of nearly $1 billion for MSR is expected to grow in the next few years, raising fears that unchecked increases could force the space agency to siphon funds from unrelated missions. Descoping options include removing one of two “Marscopters” planned for MSR, which had been included to build on the wildly successful Ingenuity rotorcraft that is now approaching 50 flights on Mars . Among other tasks, MSR’s helicopters were added as a backup option for collecting the 10-tube sample cache at Three Forks. “The mission remains complex,” Gramling said during the town hall. “We’re working to our earliest possible launch date.”

Despite the overwhelmingly intricate logistics of seeking life on Mars, the scientific riches on offer have lost none of their luster. Perseverance’s returned samples will cumulatively be only about half a kilogram, but the weight of their implications is immeasurable. Will they reveal that a second genesis of life in the universe has unfolded on the surface of Mars? For that matter, will Rosalind Franklin, once it arrives, validate the long-held suspicion that Mars’s subsurface was—or still is—habitable, too? In our winding quest to determine if we are alone in the universe, the answer may be practically within our grasp, merely waiting for us to reach out to claim it. “We won’t know until we get the samples back,” Bosak says.

Mars Science Laboratory: Curiosity Rover

Curiosity's scientific tools found chemical and mineral evidence of past habitable environments on Mars. It continues to explore the rock record from a time when Mars could have been home to microbial life.

Landing at Gale Crater, Mars Science Laboratory is assessing whether Mars ever had an environment capable of supporting microbial life. Determining past habitability on Mars gives NASA and the scientific community a better understanding of whether life could have existed on the Red Planet and, if it could have existed, an idea of where to look for it in the future.

To contribute to the four Mars exploration science goals and meet its specific goal of determining Mars' habitability, Curiosity has the following science objectives:

Biological objectives

Geological and geochemical objectives, planetary process objectives, surface radiation objective.

1. Determine the nature and inventory of organic carbon compounds 2. Inventory the chemical building blocks of life (carbon, hydrogen, nitrogen, oxygen, phosphorous, and sulfur) 3. Identify features that may represent the effects of biological processes

1. Investigate the chemical, isotopic, and mineralogical composition of the Martian surface and near-surface geological materials 2. Interpret the processes that have formed and modified rocks and soils

1. Assess long-timescale (i.e., 4-billion-year) atmospheric evolution processes 2. Determine present state, distribution, and cycling of water and carbon dioxide

Characterize the broad spectrum of surface radiation, including galactic cosmic radiation, solar proton events, and secondary neutrons

Science Highlights

With over a decade of exploration, Curiosity has unveiled the keys to some of science's most unanswered questions about Mars. Did Mars ever have the right environmental conditions to support small life forms called microbes? Early in its mission, Curiosity's scientific tools found chemical and mineral evidence of past habitable environments on Mars. It continues to explore the rock record from a time when Mars could have been home to microbial life.

Science Instruments

From cameras to environmental and atmospheric sensors, the Curiosity rover has a suite of state-of-the-art science instruments to achieve its goals.

Discover More Topics From NASA

James Webb Space Telescope

Perseverance Rover

Parker Solar Probe

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Life on Mars? This Could Be the Place NASA’s Rover Helps Us Find It.

Rocks collected by Perseverance are filled with organic molecules, and they formed in a lake that would have been habitable a few billion years ago.

By Kenneth Chang

Exploring an ancient river delta in a crater on Mars, NASA’s Perseverance rover has collected samples of two rocks that are chock-full of carbon-based molecules that could be remnants of ancient life.

The rocks formed several billion years ago when the crater was a lake, an environment where life could have existed.

“I think it’s safe to say that these are two of the most important samples that we’ll collect on this mission,” David L. Shuster, a professor of earth and planetary science at the University of California, Berkeley, who is working on the mission, said during a news conference on Thursday.

Mission scientists were careful to add that they could not say whether these molecules are actually bits of dead microbial Martians, describing them as “potential biosignatures.”

Kenneth A. Farley, a professor of geochemistry at the California Institute of Technology who serves as the project scientist for the Perseverance mission, said the carbon molecules, even though described as organic, could have also formed in chemical reactions that did not involve life.

“A key point about a potential biosignature is it compels further investigation to draw a conclusion,” he said. “We don’t yet know the significance of these findings. These rocks are exactly the kind of rocks we came to investigate.”

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Origin of life on mars: suitability and opportunities.

1. Introduction

2. materials and methods, 2.1. organic molecules and elements, 2.2. energy sources, 2.3. planetary settings, 3.1. elements and molecules on mars, 3.1.1. organics and chnops elements, 3.1.2. transition elements, 3.1.3. other key elements, 3.1.4. elements availability, 3.2. energy sources on mars, 3.3. settings on mars, 3.3.1. early mars as compared to early earth, 3.3.2. subaerial terrain proto-macrobionts, 3.3.3. suboceanic hydrothermal proto-macrobionts, 4. discussion, 4.1. when would be an ool on mars: past, present, future, 4.2. where an ool would have been on mars, 4.3. likelihood for origin of life, 4.3.1. expected value for the ool, 4.3.2. lithopanspermia, 4.4. future research, author contributions, institutional review board statement, informed consent statement, acknowledgments, conflicts of interest, abbreviations.

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Clark, B.C.; Kolb, V.M.; Steele, A.; House, C.H.; Lanza, N.L.; Gasda, P.J.; VanBommel, S.J.; Newsom, H.E.; Martínez-Frías, J. Origin of Life on Mars: Suitability and Opportunities. Life 2021 , 11 , 539. https://doi.org/10.3390/life11060539

Clark BC, Kolb VM, Steele A, House CH, Lanza NL, Gasda PJ, VanBommel SJ, Newsom HE, Martínez-Frías J. Origin of Life on Mars: Suitability and Opportunities. Life . 2021; 11(6):539. https://doi.org/10.3390/life11060539

Clark, Benton C., Vera M. Kolb, Andrew Steele, Christopher H. House, Nina L. Lanza, Patrick J. Gasda, Scott J. VanBommel, Horton E. Newsom, and Jesús Martínez-Frías. 2021. "Origin of Life on Mars: Suitability and Opportunities" Life 11, no. 6: 539. https://doi.org/10.3390/life11060539

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Life on Mars: A Definite Possibility

Was Mars once a living world? Does life continue, even today, in a holding pattern, waiting until the next global warming event comes along? Many people would like to believe so. Scientists are no exception. But so far no evidence has been found that convinces even a sizable minority of the scientific community that the red planet was ever home to life. What the evidence does indicate, though, is that Mars was once a habitable world . Life, as we know it, could have taken hold there.

The discoveries made by NASA ’s Opportunity rover at Eagle Crater earlier this year (and being extended now at Endurance Crater) leave no doubt that the area was once ‘drenched’ in water . It might have been shallow water. It might not have stuck around for long. And billions of years might have passed since it dried up. But liquid water was there, at the martian surface, and that means that living organisms might have been there, too.

So suppose that Eagle Crater – or rather, whatever land formation existed in its location when water was still around – was once alive. What type of organism might have been happy living there?

Probably something like bacteria. Even if life did gain a foothold on Mars, it’s unlikely that it ever evolved beyond the martian equivalent of terrestrial single-celled bacteria. No dinosaurs; no redwoods; no mosquitoes – not even sponges, or tiny worms. But that’s not much of a limitation, really. It took life on Earth billions of years to evolve beyond single-celled organisms. And bacteria are a hardy lot. They are amazingly diverse, various species occupying extreme niches of temperature from sub-freezing to above-boiling; floating about in sulfuric acid; getting along fine with or without oxygen. In fact, there are few habitats on Earth where one or another species of bacterium can’t survive.

What kind of microbe, then, would have been well adapted to the conditions that existed when Eagle Crater was soggy? Benton Clark III , a Mars Exploration Rover ( MER ) science team member, says his “general favorite” candidates are the sulfate-reducing bacteria of the genus Desulfovibrio . Microbiologists have identified more than 40 distinct species of this bacterium.

Eating Rocks

We tend to think of photosynthesis as the engine of life on Earth. After all, we see green plants nearly everywhere we look and virtually the entire animal kingdom is dependent on photosynthetic organisms as a source of food. Not only plants, but many microbes as well, are capable of carrying out photosynthesis. They’re photoautotrophs: they make their own food by capturing energy directly from sunlight.

But Desulfovibrio is not a photoautotroph; it’s a chemoautotroph. Chemoautotrophs also make their own food, but they don’t use photosynthesis to do it. In fact, photosynthesis came relatively late in the game of life on Earth. Early life had to get its energy from chemical interactions between rocks and dirt, water, and gases in the atmosphere. If life ever emerged on Mars, it might never have evolved beyond this primitive stage.

Desulfovibrio makes its home in a variety of habitats. Many species live in soggy soils, such as marshes and swamps. One species was discovered all snug and cozy in the intestines of a termite. All of these habitats have two things in common: there’s no oxygen present; and there’s plenty of sulfate available.

Sulfate reducers, like all chemoautotrophs, get their energy by inducing chemical reactions that transfer electrons between one molecule and another. In the case of Desulfovibrio, hydrogen donates electrons, which are accepted by sulfate compounds. Desulfovibrio, says Clark, uses “the energy that it gets by combining the hydrogen with the sulfate to make the organic compounds” it needs to grow and to reproduce.

The bedrock outcrop in Eagle Crater is chock full of sulfate salts. But finding a suitable electron donor for all that sulfate is a bit more troublesome. “My calculations indicate [that the amount of hydrogen available is] probably too low to utilize it under present conditions,” says Clark. “But if you had a little bit wetter Mars, then there [would] be more water in the atmosphere, and the hydrogen gas comes from the water” being broken down by sunlight.

So water was present; sulfate and hydrogen could have as an energy source. But to survive, life as we know it needs one more ingredient carbon. Many living things obtain their carbon by breaking down the decayed remains of other dead organisms. But some, including several species of Desulfovibrio, are capable of creating organic material from scratch, as it were, drawing this critical ingredient of life directly from carbon dioxide (CO 2 ) gas. There’s plenty of that available on Mars.

All this gives reason to hope that life that found a way to exist on Mars back in the day when water was present. No one knows how long ago that was. Or whether such a time will come again. It may be that Mars dried up billions of years ago and has remained dry ever since. If that is the case, life is unlikely to have found a way to survive until the present.

Tilting toward Life

But Mars goes through cycles of obliquity, or changes in its orbital tilt. Currently, Mars is wobbling back and forth between 15 and 35 degrees’ obliquity, on a timescale of about 100,000 years. But every million years or so, it leans over as much as 60 degrees. Along with these changes in obliquity come changes in climate and atmosphere. Some scientists speculate that during the extremes of these obliquity cycles, Mars may develop an atmosphere as thick as Earth’s, and could warm up considerably. Enough for dormant life to reawaken.

“Because the climate can change on long terms,” says Clark, ice in some regions on Mars periodically could “become liquid enough that you would be able to actually come to life and do some things – grow, multiply, and so forth – and then go back to sleep again” when the thaw cycle ended. There are organisms on Earth that, when conditions become unfavorable, can form “spores which are so resistant that they can last for a very long time. Some people think millions of years, but that’s a little controversial.”

Desulfovibrio is not such an organism. It doesn’t form spores. But its bacterial cousin, Desulfotomaculum, does. “Usually the spores form because there’s something missing, like, for example, if hydrogen’s not available, or if there’s too much [oxygen], or if there’s not sulfate. The bacteria senses that the food source is going away, and it says, ‘I’ve got to hibernate,’ and will form the spores. The spores will stay dormant for extremely long periods of time. But they still have enough machinery operative that they can actually sense that nutrients are available. And then they’ll reconvert again in just a matter of hours, if necessary, to a living, breathing bacterium, so to speak. It’s pretty amazing,” says Clark.

That is not to say that future Mars landers should arrive with life-detection equipment tuned to zero in on species of Desulfovibrio or Desulfotomaculum. There is no reason to believe that life on Mars, if it ever emerged, evolved along the same lines as life on Earth, let alone that identical species appeared on the two planets. Still, the capabilities of various organisms on Earth indicate that life on Mars – including dormant organisms that could spring to life again in another few hundred thousand years – is certainly possible.

Clark says that he doesn’t “know that there’s any organism on Earth that could really operate on Mars, but over a long period of time, as the martian environment kept changing, what you would expect is that whatever life had started out there would keep adapting to the environment as it changed.”

Detecting such organisms is another matter. Don’t look for it to happen any time soon. Spirit and Opportunity were not designed to search for signs of life, but rather to search for signs of habitability. They could be rolling over fields littered with microscopic organisms in deep sleep and they’d never know it. Even future rovers will have a tough time identifying the martian equivalent of dormant bacterial spores.

“The spores themselves are so inert,” Clark says, “it’s a question, if you find a spore, and you’re trying to detect life, how do you know it’s a spore, [and not] just a little particle of sand? And the answer is: You don’t. Unless you can find a way to make the spore do what’s called germinating, going back to the normal bacterial form.” That, however, is a challenge for another day.

Signs of Life on Mars? NASA’s Perseverance Rover Begins the Hunt

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The robotic arm on NASA’s Perseverance rover reached out to examine rocks in an area on Mars nicknamed the “Cratered Floor Fractured Rough” area in this image captured on July 10, 2021 (the 138th sol, or Martian day, of its mission).

After testing a bristling array of instruments on its robotic arm, NASA’s latest Mars rover gets down to business: probing rocks and dust for evidence of past life.

NASA’s Mars 2020 Perseverance rover has begun its search for signs of ancient life on the Red Planet. Flexing its 7-foot (2-meter) mechanical arm, the rover is testing the sensitive detectors it carries, capturing their first science readings. Along with analyzing rocks using X-rays and ultraviolet light, the six-wheeled scientist will zoom in for closeups of tiny segments of rock surfaces that might show evidence of past microbial activity.

NASA’s Perseverance Mars rover took this close-up of a rock target nicknamed “Foux” using its WATSON camera on the end of the rover’s robotic arm. The image was taken July 11, 2021, the 139th Martian day, or sol, of the mission.

Called PIXL , or Planetary Instrument for X-ray Lithochemistry, the rover’s X-ray instrument delivered unexpectedly strong science results while it was still being tested, said Abigail Allwood, PIXL’s principal investigator at NASA’s Jet Propulsion Laboratory in Southern California. Located at the end of the arm, the lunchbox-size instrument fired its X-rays at a small calibration target – used to test instrument settings – aboard Perseverance and was able to determine the composition of Martian dust clinging to the target.

“We got our best-ever composition analysis of Martian dust before it even looked at rock,” Allwood said.

That’s just a small taste of what PIXL, combined with the arm’s other instruments, is expected to reveal as it zeroes in on promising geological features over the weeks and months ahead.

Scientists say Jezero Crater was a crater lake billions of years ago, making it a choice landing site for Perseverance. The crater has long since dried out, and the rover is now picking its way across its red, broken floor .

“If life was there in Jezero Crater, the evidence of that life could be there,” said Allwood, a key member of the Perseverance “arm science” team.

PIXL, one of seven instruments aboard NASA's Perseverance Mars rover, is equipped with light diodes circling its opening to take pictures of rock targets in the dark. Using artificial intelligence, PIXL relies on the images to determine how far away it is from a target to be scanned.

To get a detailed profile of rock textures, contours, and composition, PIXL’s maps of the chemicals throughout a rock can be combined with mineral maps produced by the SHERLOC instrument and its partner, WATSON. SHERLOC – short for Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals – uses an ultraviolet laser to identify some of the minerals in the rock, while WATSON takes closeup images that scientists can use to determine grain size, roundness, and texture, all of which can help determine how the rock was formed.

Early WATSON closeups have already yielded a trove of data from Martian rocks, the scientists said, such as a variety of colors, sizes of grains in the sediment, and even the presence of “cement” between the grains. Such details can provide important clues about formation history, water flow, and ancient, potentially habitable Martian environments. And combined with those from PIXL, they can provide a broader environmental and even historical snapshot of Jezero Crater.

“What is the crater floor made out of? What were the conditions like on the crater floor?” asks Luther Beegle of JPL, SHERLOC’s principal investigator. “That does tell us a lot about the early days of Mars, and potentially how Mars formed. If we have an idea of what the history of Mars is like, we’ll be able to understand the potential for finding evidence of life.”

This data shows chemicals detected within a single rock on Mars by PIXL, one of the instruments on the end of the robotic arm aboard NASA’s Perseverance Mars rover. PIXL allows scientists to study where specific chemicals can be found within an area as small as a postage stamp.

The Science Team

While the rover has significant autonomous capabilities, such as driving itself across the Martian landscape, hundreds of earthbound scientists are still involved in analyzing results and planning further investigations.

“There are almost 500 people on the science team,” Beegle said. “The number of participants in any given action by the rover is on the order of 100. It’s great to see these scientists come to agreement in analyzing the clues, prioritizing each step, and putting together the pieces of the Jezero science puzzle.”

That will be critical when the Mars 2020 Perseverance rover collects its first samples for eventual return to Earth. They’ll be sealed in superclean metallic tubes on the Martian surface so that a future mission could collect them and send back to the home planet for further analysis.

Despite decades of investigation on the question of potential life, the Red Planet has stubbornly kept its secrets.

“Mars 2020, in my view, is the best opportunity we will have in our lifetime to address that question,” said Kenneth Williford, the deputy project scientist for Perseverance.

The geological details are critical, Allwood said, to place any indication of possible life in context, and to check scientists’ ideas about how a second example of life’s origin could come about.

Combined with other instruments on the rover, the detectors on the arm, including SHERLOC and WATSON, could make humanity’s first discovery of life beyond Earth.

More About the Mission

A key objective for Perseverance’s mission on Mars is astrobiology , including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance:

mars.nasa.gov/mars2020/

nasa.gov/perseverance

News Media Contact

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

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Article Contents

Mars exploration on the move.

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Mu-ming Poo, Mars exploration on the move, National Science Review , Volume 7, Issue 9, September 2020, Page 1413, https://doi.org/10.1093/nsr/nwaa181

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While the world is still struggling to overcome the COVID-19 pandemic, a new round of Mars exploration proceeded as planned, catching the July–August 2020 window of Earth–Mars close proximity that occurs once every 26 months. The excitement began with United Arab Emirates’ launch of the  Hope orbiter on 19 July, followed by China's launch of the Tianwen 1 (天问一号) explorer on 23 July, and NASA’s launch of the Perseverance rover on 30 July. All these probes will reach the vicinity of Mars seven months later. The successful launch of Emirates’ Hope orbiter and China's Tianwen 1 explorer into the Earth-to-Mars Hohmann transfer orbit marks the beginning of Mars exploration by these two countries, whereas the launch of NASA’s Perseverance rover is the continuation of a long series of Mars missions of the US that began in 1964.

The Emirates’ Hope orbiter was built through a collaboration between Mohammed bin Rashid Space Center in United Arab Emirates and three US universities, and it was launched at Tanegashima Island launch site using Japan's top-of-the-line H2A rocket. When it reaches Mars’ orbit, the probe will thoroughly investigate Mars’ atmosphere and weather events such as dust storms in the lower atmosphere. It will answer the questions of how and why the weather varies in different regions of Mars, and why Martian atmosphere is losing hydrogen and oxygen into space.

The Tianwen 1 Mars explorer, named after the title of a poem by the ancient Chinese poet Qu Yuan, ‘Questions to Heaven’, was launched at Wenchang launch site in Hainan Providence using China's most powerful ‘Long March 5’ (长征五号) carrier rocket. This is an ambitious ‘three steps in one’ attempt to combine circulating, landing and roving of Mars into one mission. The Tianwen 1 explorer includes an orbiter and a land explorer comprising an entry module and a rover, and it will perform exploration both in the orbit and on land, either independently or in coordination. The orbiter and rover carry a variety of cameras, detectors, spectrometers and particle analyzers to investigate the planet's ionosphere, magnetic field, geological structure, soil and mineral compositions, underground distribution of water/ice, and cosmic ray particles.

Perseverance is NASA’s fifth Mars rover, launched from Cape Canaveral Air Force Station in Florida using a United Launch Alliance Atlas V rocket. It is designed to search for astrobiological evidence of ancient microbial life on Mars. When it lands at Jezero Crater, the rover will gather rock and soil samples for future return to Earth and will investigate the planet's climate and geology and pave the way for future human exploration of Mars. Of particular interest is the light-weight Ingenuity Mars Helicopter that will be deployed by the rover for testing the feasibility of powered, controlled flight in the Martian atmosphere, whose density is only 1% that of the Earth. If Ingenuity's flight is successful, future robotic flying vehicles could offer unique low-altitude views of Mars not provided by orbiters and rovers.

Space exploration presents an ideal platform for inter-national collaboration. The best example is the International Space Station (ISS), participated in by 16 countries including Russia, US, Japan, Canada and Brazil and 11 member countries of the European Space Agency. Many scientific projects were carried out in the ISS, and the most notable one is the Alpha Magnetic Spectrometer (AMS) project led by Samuel C.C. Ting. On board ISS since 2011, AMS has collected a large amount of data on cosmic ray particles that may shed light on the nature of dark matter and antimatter. Seven Chinese research institutions have participated in the AMS international team, and the Chinese Academy of Sciences (CAS) Institute of Electrical Engineering, the Institute of High-Energy Physics, and China Academy of Launch Vehicle Technology have built a key component of ASS—a large permanent magnet, the largest example of such equipment ever shipped into space.

Understanding the mystery of the universe has been a dream of humanity ever since the dawn of civilization. Perhaps more than any other science, astronomy captures the imagination of all curious minds. Mars exploration signifies humanity's quest in the scientific frontier. It is often characterized in the media as a ‘space race’, linked to the technological competition among superpowers, but it should really be a race in the Olympian spirit. We will all get to the finishing line and share the excitement and achievement together, as exemplified by the memorable scenes of multinational astronauts working together in the confined space of the ISS. Sometime in the distant future, a space station will appear on Mars as an extension of the harmonious global village, where people of all nations and races will work together to fulfill the dream of humankind.

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• Published: 16 March 2021

Mars towards the future

Nature Astronomy volume  5 ,  page 209 ( 2021 ) Cite this article

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Three spacecraft from three different nations arrived at Mars in February 2021. Two of those nations are newcomers to Mars and the third successfully set out the path for a Mars sample return.

Despite regular launch opportunities every 26 months, every mission to Mars invariably captures headlines in the news and huge interest from the public. The 2020 launch window, however, actually had several novelties that distinguished it from the others — even without considering that it happened in the midst of a global pandemic.

First of all, this year has been unusually busy. Mars has not seen so much incoming traffic since 2003. Moreover, all three missions were successful, showing that we are getting more confident in delivering probes to Mars without glitches. Mars has long enjoyed the reputation of being a spacecraft-eating ghoul, but maybe it is time to bury this cliché: only one of the 15 missions sent to Mars since 2000 fully failed by not leaving Earth’s orbit.

One of the most significant features of the 2020 launch window is the appearance of new actors. The United Arab Emirates (UAE) and China have respectively become the fifth and sixth countries ever to reach Mars. Like the European Space Agency (ESA) and India, they succeeded at the first attempt. The widening of the exclusive club of nations exploring beyond the Earth–Moon system is always welcome, although we are far from the ‘democratization of deep space’ that we are experiencing for Earth’s orbit and have started to glimpse for the Moon.

Interestingly, the two nations opted for very different approaches to their Mars debut. The Mars Hope Probe from the UAE was conceived to answer very specific scientific questions linked to the vertical connections within the atmosphere, from the troposphere to atmospheric escape. In this sense, it has some overlap with NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) orbiter, and indeed the UAE has worked closely with members of the MAVEN team in the United States. International collaboration and knowledge exchange have been key points of the Hope mission. Tianwen-1 is instead all Chinese and also a very ambitious first attempt, consisting of a full orbiter–lander–rover package. The lander–rover composite is planned to land in Utopia Planitia in May 2021 after a thorough reconnaissance of the area by the orbiter aimed at identifying the best landing site according to scientific and technical criteria. Its scientific objectives are very different from — and complementary to — Hope’s, focusing on surface and shallow sub-surface processes and environment.

Compared to the UAE and China, NASA is the big veteran of Mars exploration. However, the Perseverance rover marks a distinct change in perspective for the US space agency. The ‘follow the water’ mantra that drove NASA’s Mars exploration since the 1990s is becoming obsolete, as we ‘follow habitability’ now. The Curiosity rover started this new trend, and Perseverance is consolidating it. But above all, while the science is surely going to be exciting, Perseverance has a clear forward-looking concept that distinguishes it from NASA’s previous rovers. The most important innovation by far is the first step towards a Mars sample return.

Actual projects for a Martian sample return have struggled to materialize due to the magnitude of its technical challenges. Now we have a clear plan: a three-step sequence (of which Perseverance carries out the first) that spans the whole decade and involves a tight collaboration between NASA and ESA. Much of Perseverance’s design revolves around sample return. The rover will drill and collect samples that will be stored in cylinders and left on the Martian surface. Cleverly, the rover will carry these samples from the different acquisition points over to a single caching area, ready for collection by the future ‘fetch’ rover. The scientific payload is also tailored for this purpose: a suite of cameras and spectrometers will allow the identification of the most interesting rocks to sample, and in situ sample analysis facilities were sacrificed to make space for the tube collection and storage. Mars sample return has always been considered at risk of being bypassed because of its high costs, but now that it is in motion it will be much harder to stop.

Perseverance’s look to the future goes beyond sample return, containing as it does a rather unprecedented set of technology experiments. First, the Ingenuity helicopter will try to perform the first controlled flight on another planet as a standalone and autonomous system. Considering the extremely thin and dust-laden atmosphere of Mars, success is not a given and Ingenuity will be a crucial test for any future airborne technology. In addition, the rover contains MOXIE (the Mars Oxygen In-Situ Resource Utilization Experiment), which is designed to release oxygen into the atmosphere of Mars after synthesizing it from locally harvested CO 2 . This is the first attempt to consciously affect the environment of a planet. While MOXIE is just a technology demonstrator and will not have any actual impact on the atmosphere of Mars, it is a first test of how we could utilize local resources to support future human missions and habitation. Resource utilization on Mars is the next challenge and, in addition to Perseverance, there are already some ongoing projects, in particular concerning water reservoirs. In this issue we present an effort to map the likelihood of water ice availability in the shallow subsurface of Mars and just last month the US, Italian, Japanese and Canadian space agencies announced a partnership for an International Mars Ice Mapper orbiter that could fly as early as 2026.

The 2020 launch window saw exciting new perspectives open up for Mars exploration, and this trend will continue in the already busy next launch windows. Martian exploration has always been fertile terrain for international scientific collaboration: we hope that these novelties will not change that and the way forward will be inclusive and concordant.

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Five reasons to explore Mars

Subscribe to the center for technology innovation newsletter, darrell m. west darrell m. west senior fellow - center for technology innovation , douglas dillon chair in governmental studies.

August 18, 2020

The recent launch of the Mars rover Perseverance is the latest U.S. space mission seeking to understand our solar system. Its expected arrival at the Red Planet in mid-February 2021 has a number of objectives linked to science and innovation. The rover is equipped with sophisticated instruments designed to search for the remains of ancient microbial life, take pictures and videos of rocks, drill for soil and rock samples, and use a small helicopter to fly around the Jezero Crater landing spot .

Mars is a valuable place for exploration because it can be reached in 6 ½ months, is a major opportunity for scientific exploration, and has been mapped and studied for several decades. The mission represents the first step in a long-term effort to bring Martian samples back to Earth, where they can be analyzed for residues of microbial life. Beyond the study of life itself, there are a number of different benefits of Mars exploration.

Understand the Origins and Ubiquity of Life

The site where Perseverance is expected to land is the place where experts believe 3.5 billion years ago held a lake filled with water and flowing rivers. It is an ideal place to search for the residues of microbial life, test new technologies, and lay the groundwork for human exploration down the road.

The mission plans to investigate whether microbial life existed on Mars billions of years ago and therefore that life is not unique to Planet Earth. As noted by Chris McKay, a research scientist at NASA’s Ames Research Science Center, that would be an extraordinary discovery. “Right here in our solar system, if life started twice , that tells us some amazing things about our universe,” he pointed out. “It means the universe is full of life. Life becomes a natural feature of the universe, not just a quirk of this odd little planet around this star.”

The question of the origins of life and its ubiquity around the universe is central to science, religion, and philosophy. For much of our existence, humans have assumed that even primitive life was unique to Planet Earth and not present in the rest of the solar system, let alone the universe. We have constructed elaborate religious and philosophical narratives around this assumption and built our identity along the notion that life is unique to Earth.

If, as many scientists expect, future space missions cast doubt on that assumption or outright disprove it by finding remnants of microbial life on other planets, it will be both invigorating and illusion-shattering. It will force humans to confront their own myths and consider alternative narratives about the universe and the place of Earth in the overall scheme of things.

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As noted in my Brookings book, Megachange , given the centrality of these issues for fundamental questions about human existence and the meaning of life, it would represent a far-reaching shift in existing human paradigms. As argued by scientist McKay, discovering evidence of ancient microbial life on Mars would lead experts to conclude that life likely is ubiquitous around the universe and not limited to Planet Earth. Humans would have to construct new theories about ourselves and our place in the universe.

Develop New Technologies

The U.S. space program has been an extraordinary catalyst for technology innovation . Everything from Global Positioning Systems and medical diagnostic tools to wireless technology and camera phones owe at least part of their creation to the space program. Space exploration required the National Aeronautics and Space Administration to learn how to communicate across wide distances, develop precise navigational tools, store, transmit, and process large amounts of data, deal with health issues through digital imaging and telemedicine, and develop collaborative tools that link scientists around the world. The space program has pioneered the miniaturization of scientific equipment and helped engineers figure out how to land and maneuver a rover from millions of miles away.

Going to Mars requires similar inventiveness. Scientists have had to figure out how to search for life in ancient rocks, drill for rock samples, take high resolution videos, develop flying machines in a place with gravity that is 40 percent lower than on Earth, send detailed information back to Earth in a timely manner, and take off from another planet. In the future, we should expect large payoffs in commercial developments from Mars exploration and advances that bring new conveniences and inventions to people.

Encourage Space Tourism

In the not too distant future, wealthy tourists likely will take trips around the Earth, visit space stations, orbit the Moon, and perhaps even take trips around Mars. For a substantial fee, they can experience weightlessness, take in the views of the entire planet, see the stars from outside the Earth’s atmosphere, and witness the wonders of other celestial bodies.

The Mars program will help with space tourism by improving engineering expertise with space docking, launches, and reentry and providing additional experience about the impact of space travel on the human body. Figuring out how weightlessness and low gravity situations alter human performance and how space radiation affects people represent just a couple areas where there are likely to be positive by-products for future travel.

The advent of space tourism will broaden human horizons in the same way international travel has exposed people to other lands and perspectives. It will show them that the Earth has a delicate ecosystem that deserves protecting and why it is important for people of differing countries to work together to solve global problems. Astronauts who have had this experience say it has altered their viewpoints and had a profound impact on their way of thinking.

Facilitate Space Mining

Many objects around the solar system are made of similar minerals and chemical compounds that exist on Earth. That means that some asteroids, moons, and planets could be rich in minerals and rare elements. Figuring out how to harvest those materials in a safe and responsible manner and bring them back to Earth represents a possible benefit of space exploration. Elements that are rare on Earth may exist elsewhere, and that could open new avenues for manufacturing, product design, and resource distribution. This mission could help resource utilization through advances gained with its Mars Oxygen Experiment (MOXIE) equipment that converts Martian carbon dioxide into oxygen. If MOXIE works as intended, it would help humans live and work on the Red Planet.

Advance Science

One of the most crucial features of humanity is our curiosity about the life, the universe, and how things operate. Exploring space provides a means to satisfy our thirst for knowledge and improve our understanding of ourselves and our place in the universe.

Space travel already has exploded centuries-old myths and promises to continue to confront our long-held assumptions about who we are and where we come from. The next decade promises to be an exciting period as scientists mine new data from space telescopes, space travel, and robotic exploration. Ten or twenty years from now, we may have answers to basic questions that have eluded humans for centuries, such as how ubiquitous life is outside of Earth, whether it is possible for humans to survive on other planets, and how planets evolve over time.

The author would like to thank Victoria E. Hamilton, staff scientist at the Southwest Research Institute, for her helpful feedback on this blog post.

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Life on Mars: Exploration & Evidence

When imagining locations where extraterrestrial life could potentially dwell, few places inspire the imagination like one of Earth's closest neighbors. For centuries, man has looked to Mars and imagined it as a home for other beings. Over the last fifty years, various missions to the red planet have sought to determine the probability of such an evolution. But how likely is life on Mars?

A habitable environment

When searching for life, most astrobiologists agree that water is key . All forms of terrestrial life require water, and while it is possible that life could evolve without the precious liquid, it is easier to search for conditions that are known to be optimal, rather than conditions we suppose could be." [ 5 Bold Claims of Alien Life  ]

This raises a problem on Mars. The planet today is dry and barren, with most of its water locked up in the polar ice caps . The planet's thin atmosphere allows radiation from the sun to irradiate the surface of the planet, adding to the environment's challenges. Evidence for water first showed up in 2000, when images from NASA's Mars Global Surveyor found gullies that appeared to have formed from flowing water.

But Mars wasn't always a desolate wasteland . Scientists think that, in the past, water may have flowed across the surface in rivers and streams, and that vast oceans covered the planet. Over time, the water was lost into space, but early conditions on the wetter planet could have been right for life to evolve. One estimate suggests that an ancient ocean could have covered as much as 19 percent of the planet's surface, compared to the 17 percent covered by Earth's Atlantic Ocean.

"With Mars losing that much water, the planet was very likely wet for a longer period of time than was previously thought, suggesting it might have been habitable for longer," said Michael Mumma, a senior scientist at Goddard, said in a statement .

It's also possible that liquid water flows on a modern Mars, either on the surface or beneath. The debate continues today on whether features known as recurring slope lineae (RSLs) form from ongoing water flows or running sand. "We've thought of RSL as possible liquid water flows, but the slopes are more like what we expect for dry sand," Colin Dundas of the U.S. Geological Survey's Astrogeology Science Center in Flagstaff, Arizona, said in a statement . "This new understanding of RSL supports other evidence that shows that Mars today is very dry.

Water beneath the surface may be even better for life. Underground water could shield potential life from harsh radiation. There's evidence for an ice deposit the size of Lake Superior. "This deposit is probably more accessible than most water ice on Mars, because it is at a relatively low latitude and it lies in a flat, smooth area where landing a spacecraft would be easier than at some of the other areas with buried ice," researcher Jack Holt of the University of Texas said in a statement .

Over the last four billion years, Earth has received a number of visitors from Mars . Our planet has been bombarded by rocks blown from the surface of the red planet, one of the few bodies in the solar system scientists have samples from. Of the 34 Martian meteorites, scientists have determined that three have the potential to carry evidence of past life on Mars.

A meteorite found in Antarctica made headlines in 1996 when scientists claimed that it could contain evidence of traces of life on Mars. Known as ALH 84001 , the Martian rock contained structures resembled the fossilized remains of bacteria-like lifeforms. Follow-up tests revealed organic material, though the debate over whether or not the material was caused by biological processes wasn't settled until 2012, when it was determined that these vital ingredients had been formed on Mars without the involvement of life .

"Mars apparently has had organic carbon chemistry for a long time," study lead author Andrew Steele, a microbiologist at the Carnegie Institution of Washington, told SPACE.com .

However, these organic molecules formed not from biology but from volcanism. Despite the rocky origin for the molecules, their organic nature may prove a positive in the hunt for life.

"We now find that Mars has organic chemistry, and on Earth, organic chemistry led to life, so what is the fate of this material on Mars, the raw material that the building blocks of life are put together from?" Steele said.

Scientists also found structures resembling fossilized nanobacteria on the Nakhla meteorite , a chunk of Mars that landed in Egypt. They determined that as much as three-fourths of the organic material found on the meteorite may not stem from contamination by Earth. However, further examination of the spherical structure, called an ovoid, revealed that it most likely formed through processes other than life.

"The consideration of possible biotic scenarios for the origin of the ovoid structure in Nakhla currently lacks any sort of compelling evidence," the scientists wrote in a study in the journal Astrobiology . "Therefore, based on the available data that we have obtained on the nature of this conspicuous ovoid structure in Nakhla, we conclude that the most reasonable explanation for its origin is that it formed through abiotic [physical, not biological] processes."

A third meteorite, the Shergotty, contains features suggestive of biofilm remnants and microbial communities.

"Biofilms provide major evidence for bacterial colonies in ancient Earth," researchers said in a 1999 conference abstract . "It is possible that some of the clusters of microfossil-like features might be colonies, although that interpretation depends on whether the individual features are truly fossilized microbes."

All of these samples provide tantalizing hints of the possibility of life in the early history of the red planet. But a fresh examination of the surface has the potential to reveal even more insights into the evolution of life on Mars.

Searching for life

When NASA set the first lander down on the Martian surface, one of the experiments performed sought traces for life. Though Viking's results were deemed inconclusive, they paved the way for other probes into the planet's environment. [ Mars Explored: Landers and Rovers Since 1971 (Infographic) ]

Exploration of Mars was put on hold for more than two decades. When examination of the planet resumed, scientists focused more on the search for habitable environments than for life, and specifically on the search for water. The slew of rovers, orbiters, and landers revealed evidence of water beneath the crust, hot springs — considered an excellent potential environment for life to evolve — and occasional rare precipitation. Although the Curiosity rover isn't a life-finding mission, there are hopes that it could pinpoint locations that later visitors might explore and analyze.

Future mission to Mars could include sample returns , bringing pieces of the Martian crust back to Earth to study. More experiments could be run by hand on Earth than can be performed by a remote robot explorer, and would be more controlled than meteorites that have lain on Earth.

"Mars 2020 will gather samples for potential return to Earth in the future. It's time for the sample-analysis community to get serious about defining and prioritizing Mars sample science, and in helping to make the case for the future missions that would get those samples home," David Beaty, co-leader of NASA's Returned Sample Science Board and chief scientist for the Mars Exploration Directorate at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, said at a 2017 workshop .

But the hunt for Martian life may be stymied by concerns over how to prevent infecting the Red Planet with Earth life. Current international policies impose heavy financial burdens that make exploring potentially habitable regions of Mars an extra challenge.

"Bottom line is that a thorough cleaning of a spacecraft aimed to in situ search for life on a special region of Mars today would easily cost around $500 million," Dirk Schulze-Makuch told SPACE.com via email. Schulze-Makuch, a researcher at Washington State University, and his colleague Alberto Fairen of Cornell University authored a commentary article published in the journal Nature Geoscience arguing for less-strict protection measures for Mars.

"With that amount of money, you can entirely finance a 'Discovery-type' mission to Mars, similar to Pathfinder or InSight," he added. "Therefore, if we'd relax planetary protection concerns in a Viking-like mission today, we could add another low-budget mission to the space program."

Are we the Martians?

The transfer of material from Mars to Earth and presumably back again has sparked some debate about the possibility of contamination early in the history of life. Some scientists argue that a meteorite from Earth could have traveled to Mars — or vice versa. Debates rage over whether or not tiny organisms would be hardy enough to survive the voyage through a freezing, airless, radiation-filled vacuum and kick off life at its new home.

The idea of such seeding is not limited to interactions with Mars. Some have proposed that debris from outside the solar system could even be responsible for spawning life on Earth. But in terms of the Red Planet, it is possible that scientists might one day find life on Mars — and it could be a close relation.

"If we find life on another planet, will it be truly alien or will it be related to us? And if so, did it spawn us or did we spawn it?" researcher Dina Pasini, of the University of Kent, questioned in a statement . "We cannot answer these questions just now, but the questions are not as farfetched as one might assume."

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Writing Life on Mars: Posthuman Imaginaries of Extraterrestrial Colonization and the NASA Mars Rover Missions

• First Online: 01 January 2022

Cite this chapter

• Jens Temmen 6  

Part of the book series: Palgrave Studies in Life Writing ((PSLW))

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Focusing on three different life narratives and practices of Mars colonization—the NASA rover missions, the technoliberal campaign to settle the red planet by space entrepreneur Elon Musk, and the critical activist project “Planetary Personhood”—Jens Temmen analyzes how, in the context of climate change debates, human colonization of other planets has been reframed as inevitable and necessary to ensure the survival of humanity. Temmen’s contribution focuses on how these “astrofuturist” narratives negotiate the utopian vision of space colonization as a transformative posthuman experience of escape from the terrestrial limits placed on humanity, and it discusses whether life writing as a format allows for a thorough and critical posthuman inquiry of humanity’s anthropocentrism.

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Scorched Earth: Discourses of Multiplanetarity, Climate Change, and Martian Terraforming in Finch and Once Upon a Time I Lived on Mars .

The Universe Decentered: Transcultural Perspectives on Astrobiology and Big History

Missions and Explorers: “Amundsen” as a Key to Reading Alice Munro’s Other Stories

Ganser, “Astrofuturism,” 36.

Ibid., 35, 37.

See Ganser, “Astrofuturism,” 36, 40. See Kilgore, “Astrofuturism,” 1, quoted in Ganser, “Astrofuturism,” 35.

Davenport, The Space Barons , 4, 123, 143–144.

See Ganser, “Astrofuturism,” 37, 40. See Redmond, “The Whiteness of Cinematic,” 348.

See Braidotti, The Posthuman , 9.

See Messeri, Placing Outer Space , 2.

See Vertesi, Seeing Like a Rover , 20.

Similar to the idea of “greenwashing” products as environmental-friendly, the concept of “double red washing” refers to how the privatization of the space industry is promoted by Musk and others as the only way to achieve the colonization of the red planet, and to how both the privatized space industry and Mars colonization are depicted as progressive measures aiming for greater social justice (see Marx, “Elon Musk is Planning”).

See Braidotti, The Posthuman , 43–44.

Opportunity’s sister rover “Spirit” had shut down in 2009 already.

See “‘My battery is low.’”

See Simon, “Opinion.”

See Butler, “Precariousness and Grievability.”

Butler analyzes how in times of war and crisis, the notion of a grievable death is a political issue of enormous significance. Focusing on 9/11 and the subsequent war in Iraq, Butler describes how public mourning can be used as a way of supporting the war effort and of constructing nationalist (non-)belonging, but also as a mode of dehumanization of the lives that are specifically constructed as ungrievable. Even though Butler’s work is deeply immersed in the specific context of warfare, her assumptions are valid for the way in which the rovers and their demise figure as a ledger for nationalistic sentiments of belonging and pride.

The playlist consists of the music that NASA staffers had sent to Opportunity along with its wake-up command after the storm had crippled him and includes songs such as David Bowie’s “Life on Mars?,” “Staying Alive” by the BeeGees, as well as Wham!‘s “Wake Me up Before You Go-Go.”

Simon, “Opinion.”

See Messeri, Placing Outer Space , 19.

Messeri, Placing Outer Space , 19.

See Messeri, Placing Outer Space , 5, 19, 34.

Braidotti, The Posthuman , 2.

Vertesi, Seeing Like a Rover , 20.

See Atanasoski and Vora, “Why the Sex Robot,” 2.

The way that the rovers seem to break barriers between technology, human, and animal, make them comparable to other posthuman icons, such as the cloned sheep Dolly, which, according to Braidotti, is an entity “no longer an animal but not yet fully a machine,” 74. The rovers, no longer a machine but not yet fully human, seem to be on that same spectrum.

Atanasoski and Vora, “Why the Sex Robot,” 6. See Markley, Dying Planet , 270.

Braidotti, The Posthuman , 43–44.

See Vertesi, Seeing Like a Rover , 7, 170–171.

Vertesi, Seeing Like a Rover , 25.

Ibid., 171.

Ibid., 176.

Keeling, “Queer OS,” 157.

See Braidotti, The Posthuman , 9, 124, 125–126. See Mbembe, Necropolitics .

Atanasoski and Vora, “Why the Sex Robot,” 1, 6. Atanasoski and Vora’s work focuses predominately on self-reproducing robots which are projected to be a vital part of the first steps to Martian colonization, but which have not yet been constructed or deployed (see ibid., 2). The way that NASA frames the current Mars rovers as links in human evolution, allows, I would argue, for a broadening of Atanasoski and Vora’s argument to apply here as well.

See Messeri, Placing Outer Space , 18, 68.

See Messeri, Placing Outer Space , 18. See Vertesi, Seeing Like a Rover , 31–32. A prominent and striking example is the influential essay by aerospace engineer Robert Zubrin, titled “The Significance of the Martian Frontier,” which advocates for Martian colonization through frontier discourses in general and by directly drawing on Frederick Jackson Turner’s infamous frontier thesis in particular, 13.

The concept of terra nullius is a core tenet of settler colonialism that relies on framing the Indigenous populations of newly “discovered” lands as less-than-human and therefore without claim to their own land (see Robertson, Conquest by Law ).

Atanasoski and Vora, “Why the Sex Robot,” 2.

See Temmen, “From HI-SEAS to Outer Space.”

See Saraf, “‘We’d Rather Eat Rocks.’”

See Messeri, Placing Outer Space , 68.

Atanasoski and Vora, “Why the Sex Robot,” 6.

Even though space agencies around the globe rely (and have relied for a long time) on private industry contractors, space travel is not a privatized business, but regulated on a national and international level. Private businesses can partner with national agencies, but they cannot conduct space travel on their own. While Musk and others have become important players as contractors, their vision includes completely privatizing space travel, which would, in their perspective, break a detrimental nation-state monopoly on space travel.

Davenport, The Space Barons , 4.

Ibid., 4–5.

See Wallace-Wells, The Uninhabitable Earth , 175–176.

Messeri, Placing Outer Space , 18.

Atanasoski and Vora, “Why the Sex Robot,” 11.

Davenport, The Space Barons , 1–2.

See Davenport, The Space Barons , 2.

Atanasoski and Vora, “Why the Sex Robot,” 1.

See Davenport, The Space Barons , 49–60, 117.

“When Slow Violence Sprints.”

Wallace-Wells, The Uninhabitable Earth , 176.

See Braidotti, The Posthuman , 5–6. See Chakrabarty, “The Climate of History,” 221–222.

See Heise, Sense of Planet , 25. See Atanasoski and Vora, “Why the Sex Robot,” 16.

Nonhuman Nonsense, “Planetary Personhood.”

See New Zealand Parliamentary Counsel Office, “Te Urewera Act 2014.”

See Atanasoski and Vora, “Why the Sex Robot,” 14.

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Temmen, J. (2021). Writing Life on Mars: Posthuman Imaginaries of Extraterrestrial Colonization and the NASA Mars Rover Missions. In: Batzke, I., Espinoza Garrido, L., Hess, L.M. (eds) Life Writing in the Posthuman Anthropocene. Palgrave Studies in Life Writing. Palgrave Macmillan, Cham. https://doi.org/10.1007/978-3-030-77973-3_8

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Essay on Life on Mars for Students and Children

500 words essay on life on mars.

Mars is the fourth planet from the sun in our solar system. Also, it is the second smallest planet in our solar system. The possibility of life on mars has aroused the interest of scientists for many years. A major reason for this interest is due to the similarity and proximity of the planet to Earth. Mars certainly gives some indications of the possibility of life.

Possibilities of Life on Mars

In the past, Mars used to look quite similar to Earth. Billions of years ago, there were certainly similarities between Mars and Earth. Furthermore, scientists believe that Mars once had a huge ocean. This ocean, experts believe, covered more of the planet’s surface than Earth’s own oceans do so currently.

Moreover, Mars was much warmer in the past that it is currently. Most noteworthy, warm temperature and water are two major requirements for life to exist. So, there is a high probability that previously there was life on Mars.

Life on Earth can exist in the harshest of circumstances. Furthermore, life exists in the most extreme places on Earth. Moreover, life on Earth is available in the extremely hot and dry deserts. Also, life exists in the extremely cold Antarctica continent. Most noteworthy, this resilience of life gives plenty of hope about life on Mars.

There are some ingredients for life that already exist on Mars. Bio signatures refer to current and past life markers. Furthermore, scientists are scouring the surface for them. Moreover, there has been an emergence of a few promising leads. One notable example is the presence of methane in Mars’s atmosphere. Most noteworthy, scientists have no idea where the methane is coming from. Therefore, a possibility arises that methane presence is due to microbes existing deep below the planet’s surface.

One important point to note is that no scratching of Mars’s surface has taken place. Furthermore, a couple of inches of scratching has taken place until now. Scientists have undertaken analysis of small pinches of soil. There may also have been a failure to detect signs of life due to the use of faulty techniques. Most noteworthy, there may be “refugee life” deep below the planet’s surface.

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Challenges to Life on Mars

First of all, almost all plants and animals cannot survive the conditions on the surface of Mars. This is due to the extremely harsh conditions on the surface of Mars.

Another major problem is the gravity of Mars. Most noteworthy, the gravity on Mars is 38% to that of Earth. Furthermore, low gravity can cause health problems like muscle loss and bone demineralization.

The climate of Mars poses another significant problem. The temperature at Mars is much colder than Earth. Most noteworthy, the mean surface temperatures of Mars range between −87 and −5 °C. Also, the coldest temperature on Earth has been −89.2 °C in Antarctica.

Mars suffers from a great scarcity of water. Most noteworthy, water discovered on Mars is less than that on Earth’s driest desert.

Other problems include the high penetration of harmful solar radiation due to the lack of ozone layer. Furthermore, global dust storms are common throughout Mars. Also, the soil of Mars is toxic due to the high concentration of chlorine.

To sum it up, life on Mars is a topic that has generated a lot of curiosity among scientists and experts. Furthermore, establishing life on Mars involves a lot of challenges. However, the hope and ambition for this purpose are well alive and present. Most noteworthy, humanity must make serious efforts for establishing life on Mars.

FAQs on Life on Mars

Q1 State any one possibility of life on Mars?

A1 One possibility of life on Mars is the resilience of life. Most noteworthy, life exists in the most extreme places on Earth.

Q2 State anyone challenge to life on Mars?

A2 One challenge to life on Mars is a great scarcity of water.

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NASA’s October Surprise: ESCAPADE Mission to Mars Set To Launch on Blue Origin’s New Glenn Rocket

NASA ’s upcoming Mars mission, ESCAPADE, aims to explore the solar wind’s effects on Mars’ atmosphere using two spacecraft. The launch, scheduled for October 13, employs Blue Origin’s New Glenn rocket, emphasizing cost-effective commercial partnerships.

NASA’s next science mission to Mars is targeted to launch no earlier than Sunday, October 13, on Blue Origin’s New Glenn rocket from Space Launch Complex 36 at Cape Canaveral Space Force Station in Florida.

The agency’s ESCAPADE (Escape and Plasma Acceleration and Dynamics Explorers) mission consists of two spacecraft, designed and built by Rocket Lab, operating as a coordinated pair. The spacecraft will investigate how a stream of particles from the Sun called the solar wind interacts with Mars’ magnetic environment and how this interaction drives the planet’s atmospheric escape.

Blue Origin LLC of Kent, Washington, was awarded a task order to provide launch service for ESCAPADE as part of the agency’s VADR (Venture-Class Acquisition of Dedicated and Rideshare) launch services contract. NASA’s venture class approach lowers launch costs for more risk-tolerant science payloads by using less agency oversight, giving the commercial company greater flexibility in managing the launch services for the mission.

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