human travel to mars nasa

Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited entirely by robots.

Mission Status

Nasa spacecraft in orbit, nasa rovers on the surface, featured topics, a fascinating mars rock.

The rock has some indications it may have hosted microbial life billions of years ago, but further research is needed.

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Mars Overview

Mars is no place for the faint-hearted. It’s dry, rocky, and bitter cold. The fourth planet from the Sun, Mars, is one of Earth's two closest planetary neighbors (Venus is the other). Mars is one of the easiest planets to spot in the night sky – it looks like a bright red point of light.

Despite being inhospitable to humans, robotic explorers – like NASA's Perseverance rover – are serving as pathfinders to eventually get humans to the surface of the Red Planet.

JUly 25, 2024

NASA’s Perseverance Rover Scientists Find Intriguing Mars Rock

The six-wheeled geologist found a fascinating rock that has some indications it may have hosted microbial life billions of years ago, but further research is needed.

Why Do We Go?

Mars is one of the most explored bodies in our solar system, and it's the only planet where we've sent rovers to explore the alien landscape. NASA missions have found lots of evidence that Mars was much wetter and warmer, with a thicker atmosphere, billions of years ago.

Mars Relay Network: Interplanetary Internet

How we explore.

Mars Sample Return

NASA and ESA (European Space Agency) are planning ways to bring the first samples of Mars material back to Earth for detailed study. 

Perseverance Rover (Mars 2020)

The Mars 2020 mission Perseverance rover is the first step of a proposed roundtrip journey to return Mars samples to Earth.

Mars Curiosity Rover (Mars Science Laboratory)

Curiosity is investigating Mars to determine whether the Red Planet was ever habitable to microbial life.

The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission is the first mission devoted to understanding the Martian upper atmosphere.

Mars Reconnaissance Orbiter

Mars Reconnaissance Orbiter searches for evidence that water persisted on the surface of Mars for a long period of time.

Mars Odyssey

Mars Odyssey mission created the first global map of chemical elements and minerals that make up the Martian surface.

Mars Resources

View the one-stop shop for all Mars iconic images, videos, and more!

News & Features

NASA’s Curiosity Rover Discovers a Surprise in a Martian Rock

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Beyond the Moon

Humans to mars.

Like the Moon, Mars is a rich destination for scientific discovery and a driver of technologies that will enable humans to travel and explore far from Earth.

Mars remains our horizon goal for human exploration because it is one of the only other places we know in the solar system where life may have existed. What we learn about the Red Planet will tell us more about our Earth’s past and future, and may help answer whether life exists beyond our home planet.

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The upcoming Artemis II mission is the first step in a long mission

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NASA recently announced the crew of its upcoming Artemis II mission, which will be the first manned trip to the moon since 1972. The launch is being billed as the first step toward getting humans to Mars , but how does NASA plan to do that? Here's everything you need to know:

How will NASA get to Mars?

The journey will start with the Artemis program, which has the goal of establishing the first long-term human outpost on the moon. From there, NASA says , they "will use what we learn on and around the moon to take the next giant leap: sending the first astronauts to Mars."

In 2022, NASA unveiled a rough outline for its first crewed Mars mission, identifying "50 points falling under four overarching categories of exploration, including transportation and habitation; moon and Mars infrastructure; operations; and science." These objectives "will inform our exploration plans at the moon and Mars for the next 20 years," said NASA Deputy Administrator Pam Melroy.

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These objectives include , among other things, "[Developing] a transportation system that can deliver large surface elements from Earth to the Martian surface," as well as "[developing] Mars surface power sufficient for the initial human Mars demonstration mission," and building "entry, descent, and landing (EDL) systems capable of delivering crew and large cargo to the Martian surface."

However, there is still a ton of work to be done, as making a human trip to Mars "will be challenging," Space.com writes. The distance itself will play a major factor. Earth and Mars are an average of 140 million miles away from each other, and it would take about 500 days round-trip to get between the two planets, "assuming the funding and technology come into play at the right time," the outlet adds. A lack of gravity would also pose a significant problem, so crews may have to live in a pressurized cabin during the mission to help acclimatize to the change.

If all goes well — and that is a big "if" — Space.com notes that NASA "envisions using a habitat-like spacecraft to ferry crew members to the red planet, using a hybrid rocket stage (powered by both chemical and electrical propulsion)." The initial mission would be made by four people, with two making the journey to the Martian surface. But since you can't live on a desolate planet by yourself, NASA estimates the crew would need at least 25 tons of supplies awaiting them on Mars, which will have been delivered by a prior rover mission.

How will Artemis II help accomplish this goal?

The mission, set to launch toward the end of 2024, will be the first crewed flight of the Orion spacecraft, the vessel that has been tapped to send humans to Mars. Both the Orion and the Space Launch System (SLS) associated with it "are critical to NASA's exploration plans at the moon and beyond," the agency writes .

The Orion capsule is specifically designed to keep humans alive during months-long missions, and "will be equipped with advanced environmental control and life support systems designed for the demands of a deep space mission," per NASA . The first step in proving that these systems are viable will be a successful Artemis II mission, which CNN reports will go beyond the moon and "potentially further than any human has traveled in history."

The upcoming mission is only a flyby, and while humans will not land on the moon until Artemis III, operating on the lunar surface requires "systems that can reliably operate far from home, support the needs of human life, and still be light enough to launch," NASA writes. As a result, "exploration of the moon and Mars is intertwined," with the moon providing a platform to test "tools, instruments, and equipment that could be used on Mars ."

When does NASA plan to go to Mars?

That could depend on how fast things develop. In 2017, then-President Donald Trump signed an order directing NASA to send humans to Mars by 2033, and former President Barack Obama had set a similar goal of a mission in the 2030s, CNET reports.

NASA Administrator Bill Nelson pushed that date back slightly, saying the agency's plan "is for humans to walk on Mars by 2040," per CNN . Nelson added that the goal was to apply "what we've learned living and operating on the moon and continue them out into the solar system."

President Biden's budget proposal for the next fiscal year included an allocation of $27 billion to NASA, of which $7.6 billion would be used for deep-space exploration. However, negotiations on a budget deal are ongoing between Congress and the White House, so it remains to be seen how much of these potential NASA funds will actually see the light of day.

Who will go?

That probably won't be decided for years to come. Former NASA Administrator Jim Bridenstine said in 2019 that "we could very well see the first person on Mars be a woman," per Space.com , but no specifics regarding an astronaut class were given. Artemis III is expected to land both the first woman and first person of color on the moon, so it won't come as much of a surprise if a similarly diverse group heads to the red planet. Elon Musk, who has worked alongside NASA via his spaceflight company SpaceX, has said he believes humans will be on Mars by 2029 at the latest, but he hasn't provided any names either.

For now, though, the question of who will be the first person to place their boots on the Martian surface remains a mystery.

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 Justin Klawans has worked as a staff writer at The Week since 2022. He began his career covering local news before joining Newsweek as a breaking news reporter, where he wrote about politics, national and global affairs, business, crime, sports, film, television and other Hollywood news. Justin has also freelanced for outlets including Collider and United Press International.  

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Science News

Space experts say sending humans to mars worth the risk.

Summit takes stock of hurdles, technologies, support needed to reach Red Planet by 2030s

MISSION TO MARS   By the 2030s, NASA and the aerospace industry want to send a crew to explore Mars, seen in this simulated image based on data from the Mars Global Surveyor orbiter.

JPL-Caltech/NASA

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By Christopher Crockett

May 24, 2016 at 12:00 pm

WASHINGTON — There’s a long-standing joke that NASA is always 20 years from putting astronauts on Mars. Mission details shared at a recent summit shows that the space agency is right on schedule. A to-do list from 2015 looks remarkably similar to one compiled in 1990. One difference: NASA is now building a rocket and test-driving technologies needed to get a crew to Mars. But the specifics for the longest road trip in history — and what astronauts will do once they arrive — remain an open question.

“Are we going to just send them there to explore and do things that we could do robotically though slower, or can we raise the bar?” asked planetary scientist Jim Bell during the Humans to Mars summit . “We need to make sure that what these folks are being asked to do is worthy of the risk to their lives,” said Bell, of Arizona State University in Tempe.

The three-day symposium, which ended May 19, was organized by Explore Mars Inc., a nonprofit dedicated to putting astronauts on Mars by the 2030s.

While the summit didn’t break new scientific ground, it did bring together planetary scientists , space enthusiasts and representatives from both NASA and the aerospace industry to talk about the challenges facing a crewed mission to Mars and rough ideas for how to get there.

Part of the appeal in sending humans is the pace of discovery. Drilling just one hole with the Curiosity rover, which has been exploring Gale Crater on Mars since August 2012 ( SN: 5/2/2015, p. 24 ), currently takes about a week. “It’s a laborious, frustrating, wonderful — frustrating — multiday process,” said Bell.

Humans also can react to novel situations, make quick decisions and see things in a way robotic eyes cannot. “A robot explorer is nowhere near as good as what a human geologist can do,” says Ramses Ramirez, a planetary scientist at Cornell University. “There’s just a lot more freedom.”

Researchers saw the human advantage firsthand in 1997 when they sent a rover called Nomad on a 45-day trek across the Atacama Desert in Chile. Nomad was controlled by operators in the United States to simulate operating a robot on another planet. Humans at the rover site provided a reality check on the data Nomad sent back. “There was a qualitative difference,” says Edwin Kite, a planetary scientist at the University of Chicago. And it wasn’t just that the geologists could do things faster. “The robots were driving past evidence of life that humans were finding very obvious.”

To get astronauts ready to explore Mars, the Apollo program is a good template, said Jim Head, a geologist at Brown University who helped train the Apollo astronauts. “Our strategy was called t-cubed: train them, trust them and turn them loose.” While each of the moon expeditions had a plan, the astronauts were trusted to use their judgment. Apollo 15 astronaut David Scott, for example, came across a chunk of deep lunar crust that researchers hoped to find although it wasn’t at a planned stop. “He spotted it three meters away,” said Head. “He saw it shining and recognized it immediately. That’s exploration.”

Despite a lack of clear goals for a jaunt to Mars, NASA is forging ahead. The Orion crew capsule has already been to space once; a 2014 launch atop a Delta IV Heavy rocket sent an uncrewed Orion 5,800 kilometers into space before it splashed down in the Pacific Ocean ( SN Online: 12/5/2014 ). And construction of the Space Launch System, a rocket intended to hurl humans at the moon and Mars, is under way. The first test flight, scheduled for October 2018, will send Orion on a multiday uncrewed trip around the moon. NASA hopes to put astronauts onboard for a lunar orbit in 2021.

Meanwhile, the crew aboard the International Space Station is testing technologies that will keep humans healthy and happy during an interplanetary cruise. Astronaut Scott Kelly recently completed a nearly yearlong visit to the station intended to reveal the effects of long-duration space travel on the human body ( SN Online: 2/29/2016 ). And on April 10, a prototype inflatable habitat — the Bigelow Expandable Activity Module — arrived at the station and was attached to a docking port six days later. The station crew will inflate the module for the first time on May 26. No one will live in it, but over the next two years, astronauts will collect data on how well the habitat handles radiation, temperature extremes and run-ins with space debris.  

Beyond that, the plans get fuzzy. The general idea is to construct an outpost in orbit around the moon as a testing and staging ground starting in the late 2020s. The first crew to Mars might land on the planet — or might not. One idea is to set up camp in Mars orbit; from there, astronauts could operate robots on the surface without long communication delays. Another idea has humans touching down on one of Mars’ two moons, Phobos or Deimos. When crews do land on the Martian surface, NASA envisions establishing a base from which astronauts could plan expeditions.

 With so few details, it’s difficult for the space agency to identify specific technologies to invest in. “There have been lots of studies — we get a lot of grief that it’s nothing but studies,” said Bret Drake, an engineer at the Aerospace Corp. in El Segundo, Calif. “But out of the studies, there are a lot of common things that come to the top no matter what path you take.”

Any mission to Mars has to support astronauts for roughly 500 to 1,000 days. The mission has to deal with round-trip communication delays of up to 42 minutes. It will need the ability to land roughly 40-ton payloads on the surface of Mars (current robotic missions drop about a ton). Living off the land is also key, making use of local water and minerals. And astronauts need the ability to not just survive, but drive around and explore. “We want to land in a safe place, which is going to be geologically boring, but we want to go to exciting locations,” said Drake.

The technical and logistical challenges might be the easiest part. “We do know enough to pull this off,” Ramirez says. “The biggest problem is political will.” Congress has yet to sign off on funding this adventure (nor has NASA presented a budget — expected to be in the hundreds of billions of dollars), and future administrations could decide to kill it.

Multiple summit speakers stressed the importance of using technology that is proven or under development — no exotic engines or rotating artificial gravity habitats for now. And a series of small missions —baby steps to the moon and an asteroid before committing to Mars — could show progress that might help keep momentum (and public interest) alive.

“We thought going to the moon was impossible, but we got there,” says Ramirez. “If we dedicate ourselves as a nation to do something crazy, we’ll do it. I have no doubt.”

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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.

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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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How NASA and SpaceX Will Get People From Earth to Mars and Safely Back Again

By Chris James, The University of Queensland April 25, 2021

This artist’s concept depicts astronauts and human habitats on Mars. NASA’s Mars Perseverance rover carries a number of technologies that could make Mars safer and easier to explore for humans. Credit: NASA

There are many things humanity must overcome before any return journey to Mars is launched.

The two major players are NASA and SpaceX , which work together intimately on missions to the International Space Station but have competing ideas of what a crewed Mars mission would look like.

Size matters

The biggest challenge (or constraint) is the mass of the payload (spacecraft, people, fuel, supplies, etc.) needed to make the journey.

We still talk about launching something into space being like launching its weight in gold.

The payload mass is usually just a small percentage of the total mass of the launch vehicle.

For example, the Saturn V rocket that launched Apollo 11 to the Moon weighed 3,000 tonnes.

But it could launch only 140 tonnes (5% of its initial launch mass) to low Earth orbit, and 50 tonnes (less than 2% of its initial launch mass) to the Moon.

Mass constrains the size of a Mars spacecraft and what it can do in space. Every maneuver costs fuel to fire rocket motors, and this fuel must currently be carried into space on the spacecraft.

SpaceX’s plan is for its crewed Starship vehicle to be refueled in space by a separately launched fuel tanker. That means much more fuel can be carried into orbit than could be carried on a single launch.

Concept art of SpaceX’s Dragon landing on Mars. Credit: SpaceX

Time matters

Another challenge, intimately connected with fuel, is time.

Missions that send spacecraft with no crew to the outer planets often travel complex trajectories around the Sun. They use what are called gravity assist maneuvers to effectively slingshot around different planets to gain enough momentum to reach their target.

This saves a lot of fuel, but can result in missions that take years to reach their destinations. Clearly, this is something humans would not want to do.

Both Earth and Mars have (almost) circular orbits and a maneuver known as the Hohmann transfer is the most fuel-efficient way to travel between two planets. Basically, without going into too much detail, this is where a spacecraft does a single burn into an elliptical transfer orbit from one planet to the other.

A Hohmann transfer between Earth and Mars takes around 259 days (between eight and nine months) and is only possible approximately every two years due to the different orbits around the Sun of Earth and Mars.

A spacecraft could reach Mars in a shorter time (SpaceX is claiming six months) but — you guessed it — it would cost more fuel to do it that way.

Mars and Earth have few similarities. Credit: NASA/JPL-Caltech

Safe landing

Suppose our spacecraft and crew get to Mars. The next challenge is landing.

A spacecraft entering Earth is able to use the drag generated by interaction with the atmosphere to slow down. This allows the craft to land safely on the Earth’s surface (provided it can survive the related heating).

But the atmosphere on Mars is about 100 times thinner than Earth’s. That means less potential for drag, so it isn’t possible to land safely without some kind of aid.

Some missions have landed on airbags (such as NASA’s Pathfinder mission) while others have used thrusters (NASA’s Phoenix mission). The latter, once again, requires more fuel.

Life on Mars

A Martian day lasts 24 hours and 37 minutes but the similarities with Earth stop there.

The thin atmosphere on Mars means it can’t retain heat as well as Earth does, so life on Mars is characterized by large extremes in temperature during the day/night cycle.

Mars has a maximum temperature of 30℃ (86ºF), which sounds quite pleasant, but its minimum temperature is -140℃ (-220ºF), and its average temperature is -63℃ (-81ºF) . The average winter temperature at the Earth’s South Pole is about -49℃ (-56ºF) .

So we need to be very selective about where we choose to live on Mars and how we manage temperature during the night.

The gravity on Mars is 38% of Earth’s (so you’d feel lighter) but the air is principally carbon dioxide (CO₂) with several percent of nitrogen, so it’s completely unbreathable. We would need to build a climate-controlled place just to live there.

SpaceX plans to launch several cargo flights including critical infrastructure such as greenhouses, solar panels and — you guessed it — a fuel-production facility for return missions to Earth.

Life on Mars would be possible and several simulation trials have already been done on Earth to see how people would cope with such an existence.

This illustration shows NASA astronauts working on the surface of Mars. A helicopter similar to the Ingenuity Mars Helicopter is airborne at left. Ingenuity is being carried aboard the Perseverance rover; it was recently deployed to the Martian surface to test whether future helicopters could accompany robotic and human missions. Credit: NASA

Return to Earth

The final challenge is the return journey and getting people safely back to Earth.

Apollo 11 entered Earth’s atmosphere at about 40,000km/h (25,000 mph), which is just below the velocity required to escape Earth’s orbit.

Spacecraft returning from Mars will have re-entry velocities from 47,000km/h to 54,000km/h (29,000 mph to 34,000 mph), depending on the orbit they use to arrive at Earth.

They could slow down into low orbit around Earth to around 28,800km/h (17,900 mph) before entering our atmosphere but — you guessed it — they’d need extra fuel to do that.

If they just barrel into the atmosphere, it will do all of the deceleration for them. We just need to make sure we don’t kill the astronauts with G-forces or burn them up due to excess heating.

These are just some of the challenges facing a Mars mission and all of the technological building blocks to achieve this are there. We just need to spend the time and the money and bring it all together.

And we need to return people safely back to Earth, mission accomplished. Credit: NASA

Written by Chris James, Lecturer, Centre for Hypersonics, The University of Queensland.

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17 comments on "how nasa and spacex will get people from earth to mars and safely back again".

The main issue being ignored is the need for artificial gravity in route. Without artificial gravity in route the astronauts will have to crawl out of the spaceship once on Mars. A fully functioning astronaut is one who has been conditioned to the gravity on Mars, or Earth, during the journey. Treadmills be damned, use a revolving capsule to live and work in during the trip. Go into microgravity as required but not all of the time.

One way to get to Mars faster would be to go towards the moon, swing around the moon. Then use the Earth for gravity assist to Mars. Might then have to wait for the right time for the position of the moon.

Why? Why go there? Won’t we just start messing with the climate there, ruining the environment there like we’re doing here?

Not to mention all of the stellar and cosmic radiation that the crew would likely absorb in transit and on the surface.

So Chris, has the ‘Cabin Fever’ problem been addressed? You do know what I mean by that don’t you? Astronauts all cooped up and nowhere to go; to get away from each other, take a space stroll, some solitude, alone time. Anything to keep from killing each other. Eh?

No mention of the radiation issues. Both in deep space and on Mars. You may survive the mission only to be riddled with cancer on your return.

However…

“Space is the natural habitat of humans. A planet, is after all, is a object in space.” – Frank Herbert

So….. where’s the Boring tunneler? Clearly Elon’s companies on Earth are just a trial run and funding source for Mars. They’ll have an entire subterranean city and solar+storage farm built before anyone steps foot on the Red Planet.

Wouldn’t it be more secure to live be on Mars underground? Elon Musk’s borer would make short work of it. Especially if it could be done remotely.

Improve earth.stop spoiling earth.Lets make earth heaven again

What about if we all stop for a moment and better think about how to save our own planet earth 🌎 which is suffering due to our negligence! Let’s make our own paradise and then if you want to leave in Jupiter! Go ahead and do it! But let’s save our own planet first! Stop destroying it.

What about if we all stop for a moment and better think about how to save our own planet earth 🌎 which is suffering due to our negligence! Let’s make our own paradise and then if you want to live in Jupiter! Go ahead and do it! But let’s save our own planet first! Stop destroying it. Spending millions of dollars in stupid stuff while our beautiful sea lions’ home have been destroy due to climate change! WHAT ABOUT IF WE THINK FIRST HOW WE CAN RECOVER OUR MOTHER EARTH 🌎 FIRST!!!

I think this will never happen as there is no signs in any religion discussing life expect this planet. This will not happen.

If humans are sent to Mars it should be with the intention of it being permanent. Not like it was going to the moon and then not going back now going on 50 plus years. Just make the commitment like Kennedy did and do it! Life’s a dance, you learn as you go.

I agree there are lots of issues with traveling to Mars

Well the climate change is because of Joe Biden so lets thank him for killing all our precious animals effected by this stupid Presidential decision on f’ing with our climate change acting like there ain’t nothing at risk with trying to change it. honestly Trump is our only saviour and I’m Mexican and had family taken by immigration but Trump has more potential than Biden ever will. Biden is hurting us Mexican more than Trump ever had. by taking the jobs we came to the US 🇺🇸 for in the first place climate change is not what we need. And our presence on Mars should and will help the chance at further life on Mars even though death is a possibility and will happen but it will also help transforming Mars to a liveable planet in the process.

There are so many issues going there. The landing might be one of the trickiest since they need a lot of supplies with them. Enough food (edible and healthy), oxygen and water. And also having enough fuel to go back. I do not see this happening any time soon.

why cracking heads for what is not necessary knowing that death will still come. pls use your time For God.

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For Humans to Reach Mars, Advances Are Needed in Space Nuclear Propulsion Technologies

WASHINGTON — Using nuclear propulsion technologies to support a human mission to Mars in 2039 will require NASA to pursue an aggressive and urgent technology development program, says a new report from the National Academies of Sciences, Engineering, and Medicine.

NASA should commit within the year to conducting an extensive and objective assessment of the merits and challenges of using different types of space nuclear propulsion systems and to making significant technology investments this decade. Such a program must include subsystem development, prototype systems, ground testing, and cargo missions as a means of flight qualification prior to first crewed use, the report says. 

Space Nuclear Propulsion for Human Mars Exploration assesses the primary challenges, merits, and risks for developing a nuclear electric propulsion (NEP) system and a nuclear thermal propulsion (NTP) system for a human mission to Mars. While NEP converts the thermal energy from a nuclear reactor into electrical energy to power electric thrusters, NTP uses the thermal energy from a nuclear reactor to heat a rocket propellant and create thrust. Each system has its own advantages and limitations for use in a crewed mission to Mars.

“Safely transporting astronauts to and from Mars will require advances in propulsion systems to develop spacecraft that are up to the challenge,” said Roger Myers, owner of R. Myers Consulting and co-chair of the committee that wrote the report. “Nuclear propulsion systems have the potential to substantially reduce trip time compared to non-nuclear approaches. Synergy with other space mission applications and terrestrial power programs is also significant and will bring about added value.”

Studies comparing NEP and NTP systems are needed to assess the viability of each system for a crewed mission to Mars. Given the need to send multiple cargo missions to Mars prior to the first crewed mission, NASA should use those cargo missions as a means of flight qualification of the selected nuclear propulsion system before it is incorporated into the first crewed mission.

NEP and NTP each have challenges, which are identified in the report.  The fundamental challenge for developing an NEP system is scaling up the operating power for each subsystem, something that requires power levels that are orders of magnitude greater than have ever been achieved to date. Another challenge is developing a compatible chemical propulsion system to provide the primary thrust when departing Earth’s orbit and when entering and departing Mars’ orbit. The fundamental challenge facing an NTP system is the ability to heat its propellant to the proper temperature, approximately 2,700 K. Other challenges include the long-term storage of liquid hydrogen in space with minimal loss; the need to rapidly bring an NTP system to full operating temperature, preferably in under one minute; and the need to develop full-scale ground test facilities that can safely capture the NTP exhaust.

“Space nuclear propulsion technology shows great potential to facilitate the human exploration of Mars,” said Bobby Braun, director for planetary science at the Jet Propulsion Laboratory and co-chair of the committee that wrote the report. “However, significant acceleration in the pace of technology maturation is required if NASA and its partners are to complete this mission within the stated timeline.”

The study — undertaken by the Space Nuclear Propulsion Technologies Committee — was sponsored by NASA. The National Academies are private, nonprofit institutions that provide independent, objective analysis and advice to the nation to solve complex problems and inform public policy decisions related to science, technology, and medicine. They operate under an 1863 congressional charter to the National Academy of Sciences, signed by President Lincoln.

Contact: Andrew Robinson, Media Relations Associate Office of News and Public Information 202-334-2138; [email protected]

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Space Nuclear Propulsion for Human Mars Exploration

Space Nuclear Propulsion for Human Mars Exploration identifies primary technical and programmatic challenges, merits, and risks for developing and demonstrating space nuclear propulsion technologies of interest to future exploration missions. This report presents key milestones and a top-level development and demonstration roadmap for performance nuclear thermal propulsion and nuclear electric propulsion systems and identifies missions that could be enabled by successful development of each technology.

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Why haven’t humans reached Mars?

When it comes to interplanetary destinations in our solar system beyond Earth, there isn’t a lot of great options when it comes to weather, conditions, or even simply solid ground. Our near neighbor Venus is so hot we’d burn up before getting anywhere near solid ground. Pluto and breaks the thermometer in the opposite direction with temperatures as cold as -400 degrees Fahrenheit (-240 degrees Celsius). Meanwhile, Neptune, Uranus, Saturn, and Jupiter are mostly made up of toxic gases that would kill us even if they did have solid ground to walk on. And that’s without even mentioning the storms.

Mars is really the only planet that sits within the habitable orbit around our sun. After more than a half century, humans have walked on the moon and delivered spacecraft that has flown to Pluto and even left the edges of our solar system . We’ve even landed several spacecraft on Mars, including the NASA Perseverance rover and China’s Zhurong rover currently moving around the planet and beaming back photos and other valuable information as we speak.

So why haven’t humans yet traveled to Mars?

According to NASA, there are a number of obstacles that we still need to overcome before sending a human mission to the planet, including technological innovation and a better understanding of the human body, mind and how we might adapt to life on another planet.

In short, these obstacles can be summarized into three major problems, say Michelle Rucker, lead of NASA’s Human Mars Architecture Team at NASA’s Johnson Space Center and Jeffrey Sheehy, chief engineer of the NASA Space Technology Mission Directorate: Get there, land there, live there and leave there.

A long voyage

“The first obstacle is just the sheer distance,” Rucker says. The Red Planet is about 34 million miles (55 million kilometers) away at its closest point . But the distance to Mars isn’t always the same. The Earth and Mars orbit the sun at different distances and speeds, meaning that there are certain more optimal periods to travel between the two, especially considering the idea is to not just to make it to Mars quickly, but to make it back.

“The trains to Mars are every 26 months,” Sheehy says, adding that the last such window occurred in July 2020. That last train was perhaps the busiest period ever seen for interplanetary travel—three uncrewed Mars missions were launched last summer in the space of two weeks.

All 26-month windows are not the same, though. Sheehy notes that on top of this, there is a larger roughly 15-year cycle when that window is even more favorable than others. But Sheehy says that a vehicle optimized to reach the planet during the most favorable opportunity might not be necessarily the same we’d need for other years. Focusing all our efforts on reaching Mars in that window would mean we’d only have a chance every 15 years—it would be something of a “one-trick pony” in other words.

Technology of course plays a role in all of this. Most rockets that we’ve launched out of the atmosphere have been propelled by rocket fuel. But this fuel for an all-chemical propulsion system would take a lot of space, and wouldn’t be optimal for the longest travel times. To reach Mars quicker and more often a system based on nuclear thermal propulsion or nuclear electric propulsion would be more effective—and that’s if we set our sights low in terms of ship size, Sheehy says. His organization is working on several different nuclear fission technologies, including a fission surface power system. They plan to demonstrate one on the moon.

The human problem

Aside from technology, we also need to learn more about how humans—creatures that evolved to live in the Earth’s atmosphere with the Earth’s gravity—are going to cope with being in a low gravity, close proximity, close environment situation on spaceships for several months of transit.

Work on this has been underway for some time, whether it’s studying how astronauts living on the International Space Station cope with the isolation and low gravity up there, and how they cope when coming back to Earth. The various lunar missions have also revealed how the astronauts there dealt with the low-gravity situation there

Furthermore, missions like NASA’s CHAPEA , a planned yearlong Mars simulation, will also informing scientists about what kind of problems might arise with a small group of people over a long mission. Other ongoing research missions in Antarctica can also help inform us what to expect. These kinds of questions are important for determining how long it takes, and how many people are needed, to pull off basic tasks.

Another concern is how humans might be able to manage living in small confined spaces for a long time without much outside contact. “If you are tired of the food you’re eating you can’t say ‘Let’s order a pizza,’” Rucker says.

But another tool to help us learn how to cope with unexpected challenges will be the Artemis mission , which is working to keep a sustainable population on the moon. Many of the technologies for day to day living on the moon, as well as how living conditions might affect the people there, will help to inform a future Mars mission.

Getting to Mars’ orbit is only half the battle. The other challenge is landing on the Red Planet safely, though not necessarily in one piece. Sheehy says that NASA is working on developing an inflatable decelerator —something like a reverse parachute that would protect and slow the landing craft while penetrating the atmosphere. To actually land, the craft would need something like supersonic retropulsion—basically jets on the bottom that reverse the massive thrust enough to bring the craft safely to the ground.

To overcome the challenge of developing this, Sheehy says that NASA plans to launch such a system into our orbit then land it back on Earth to see if it works.

Once on the ground, another potential obstacle is the dust storms. Dust proved to be a major irritant to astronauts on the moon. Since no wind or other forces erode the particles, the dust was sharp and chafing on parts of astronauts’ suits. It got everywhere, and irritated the eyes.

Mars dust may not be quite so sharp since there are erosive forces there, but the dust storms can be massive—in 2018 the rover Opportunity went offline after one bad tempest there. Rucker says that researchers have learned a lot about these Martian dust storms, but they’re still not quite sure if they’ve witnessed the worst of them.

Aside from the risk to any astronauts or equipment on the planet, the storms also kick up enough dust to block sunlight, meaning any solar-powered equipment may not work well for a period.

Equipment is a serious concern while on the planet as well. Sheehy says that any human mission to Mars would likely need to be preceded by a cargo delivery.

“Those things would be put there and checked out before we even commit to sending astronauts,” he says.

Other obstacles to overcome would be the building of the ship to travel there. Sheehy and Rucker estimate it would at least need to be the size of a football field in length, depending on the propulsion system technology we go with and how many people we ultimately decide to send. Roughly anything from a little smaller than the International Space Station in size to significantly bigger.

Both believe that we might get there in the 2030s. The next most favorable window for sending humans on a relatively quick round-trip to Mars would be in 2033, but it’s unclear whether politics, budget and technology will be ready by then.

Until then, we’re learning more every day.

“We are laying a lot of the ground work for going to Mars,” Rucker says.

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How long does it take to get to Mars?

We explore how long it takes to get to Mars and the factors that affect a journey to the Red Planet.

• Distance to Mars
• Traveling at the speed of light

Fastest spacecraft so far

Mars travel time q&a with an expert.

• Travel time calculation problems
• Past mission's travel times

Additional resources

Ever wondered how long does it take to get to Mars? 

The answer depends on several factors, ranging from the position of Earth and Mars to the technology that would propel you there. According to NASA , a one-way trip to the Red Planet would take about nine months . If you wanted to make it a round-trip , all in all, it would take about 21 months as you will need to wait about three months on Mars to make sure Earth and Mars are in a suitable location to make the trip back home. 

We take a look at how long a trip to the Red Planet would take using available technology and explore some of the factors that would affect your travel time.

Related: Curiosity rover: 15 awe-inspiring photos of Mars (gallery) 

How far away is Mars?

To determine how long it will take to reach Mars, we must first know the distance between the two planets.

Mars is the fourth planet from the sun, and the second closest to Earth (Venus is the closest). But the distance between Earth and Mars is constantly changing as they travel around the sun .

In theory, the closest that Earth and Mars would approach each other would be when Mars is at its closest point to the sun (perihelion) and Earth is at its farthest (aphelion). This would put the planets only 33.9 million miles (54.6 million kilometers) apart. However, this has never happened in recorded history. The closest recorded approach of the two planets occurred in 2003 when they were only 34.8 million miles (56 million km) apart.

The two planets are farthest apart when they are both at their farthest from the sun, on opposite sides of the star. At this point, they can be 250 million miles (401 million km) apart.

The average distance between Earth and Mars is 140 million miles (225 million km).

Related: What is the temperature on Mars?

How long would it take to travel to Mars at the speed of light?

Light travels at approximately 186,282 miles per second (299,792 km per second). Therefore, a light shining from the surface of Mars would take the following amount of time to reach Earth (or vice versa):

• Closest possible approach: 182 seconds, or 3.03 minutes
• Closest recorded approach: 187 seconds, or 3.11 minutes
• Farthest approach: 1,342 seconds, or 22.4 minutes
• On average: 751 seconds, or just over 12.5 minutes

The fastest spacecraft is NASA 's Parker Solar Probe , as it keeps breaking its own speed records as it moves closer to the sun. On Nov 21, 2021, the Parker Solar Probe reached a top speed of 101 miles (163 kilometers) per second during its 10th close flyby of our star, which translates to a phenomenal 364,621 mph (586,000 kph). According to a NASA statement , when the Parker Solar Probe comes within 4 million miles (6.2 million kilometers) of the solar surface in December 2024, the spacecraft's speed will top 430,000 miles per hour (692,000 kph)!

So if you were theoretically able to hitch a ride on the Parker Solar Probe and take it on a detour from its sun-focused mission to travel in a straight line from Earth to Mars, traveling at the speeds the probe reaches during its 10th flyby (101 miles per second), the time it would take you to get to Mars would be:

• Closest possible approach: 93 hours 
• Closest recorded approach: 95 hours  
• Farthest approach: 686 hours (28.5 days)  
• On average: 384 hours (16 days)  

We asked Michael Khan, ESA Senior Mission Analyst some frequently asked questions about travel times to Mars. 

Michael Khan is a Senior Mission Analyst for the European Space Agency (ESA). His work involves studying the orbital mechanics for journeys to planetary bodies including Mars.

How long does it take to get to Mars & what affects the travel time?

The time it takes to get from one celestial body to another depends largely on the energy that one is willing to expend. Here  "energy" refers to the effort put in by the launch vehicle and the sum of the maneuvers of the rocket motors aboard the spacecraft, and the amount of propellant that is used. In space travel, everything boils down to energy. Spaceflight is the clever management of energy.

Some common solutions for transfers to the moon are 1) the Hohmann-like transfer and 2) the Free Return Transfer. The Hohmann Transfer is often referred to as the one that requires the lowest energy, but that is true only if you want the transfer to last only a few days and, in addition, if some constraints on the launch apply. Things get very complicated from there on, so I won't go into details.

Concerning transfers to Mars, these are by necessity interplanetary transfers, i.e., orbits that have the sun as central body. Otherwise, much of what was said above applies: the issue remains the expense of energy. An additional complication lies in the fact that the Mars orbit is quite eccentric and also its orbit plane is inclined with respect to that of the Earth. And of course, Mars requires longer to orbit the sun than the Earth does. All of this is taken into account in a common type of diagram called the "pork chop plot", which essentially tells you the required dates of departure and arrival and the amount of energy required.

The "pork chop plot" shows the trajectory expert that opportunities for Mars transfers arise around every 25-26 months, and that these transfers are subdivided into different classes, one that is a bit faster, with typically around 5-8 months and the other that takes about 7-11 months. There are also transfers that take a lot longer, but I’m not talking about those here. Mostly, but not always, the second, slower one turns out to be more efficient energy-wise. A rule of thumb is that the transfer to Mars takes around as long as the human period of gestation, approximately 9 months. But that really is no more than an approximate value; you still have to do all the math to find out what applies to a specific date.

Why are journey times a lot slower for spacecraft intending to orbit or land on the target body e.g. Mars compared to those that are just going to fly by?

If you want your spacecraft to enter Mars orbit or to land on the surface, you add a lot of constraints to the design problem. For an orbiter, you have to consider the significant amount of propellant required for orbit insertion, while for a lander, you have to design and build a heat shield that can withstand the loads of atmospheric entry. Usually, this will mean that the arrival velocity of Mars cannot exceed a certain boundary. Adding this constraint to the trajectory optimisation problem will limit the range of solutions you obtain to transfers that are Hohmann-like. This usually leads to an increase in transfer duration.

The problems with calculating travel times to Mars

The problem with the previous calculations is that they measure the distance between the two planets as a straight line. Traveling through the farthest passing of Earth and Mars would involve a trip directly through the sun, while spacecraft must of necessity move in orbit around the solar system's star.

Although this isn't a problem for the closest approach, when the planets are on the same side of the sun, another problem exists. The numbers also assume that the two planets remain at a constant distance; that is, when a probe is launched from Earth while the two planets are at the closest approach, Mars would remain the same distance away over the length of time it took the probe to travel. 

Related: A brief history of Mars missions

In reality, however, the planets are moving at different rates during their orbits around the sun. Engineers must calculate the ideal orbits for sending a spacecraft from Earth to Mars. Like throwing a dart at a moving target from a moving vehicle, they must calculate where the planet will be when the spacecraft arrives, not where it is when it leaves Earth. 

It's also not possible to travel as fast as you can possibly go if your aim is to eventually orbit your target planet. Spacecraft need to arrive slow enough to be able to perform orbit insertion maneuvers and not just zip straight past their intended destination. 

The travel time to Mars also depends on the technological developments of propulsion systems.

According to NASA Goddard Space Flight Center's website, the ideal lineup for a launch to Mars would get you to the planet in roughly nine months. The website quotes physics professor Craig C. Patten , of the University of California, San Diego:

"It takes the Earth one year to orbit the sun and it takes Mars about 1.9 years (say 2 years for easy calculation) to orbit the sun. The elliptical orbit which carries you from Earth to Mars is longer than Earth's orbit but shorter than Mars' orbit. Accordingly, we can estimate the time it would take to complete this orbit by averaging the lengths of Earth's orbit and Mars' orbit. Therefore, it would take about one and a half years to complete the elliptical orbit.

"In the nine months it takes to get to Mars, Mars moves a considerable distance around in its orbit, about three-eighths of the way around the sun. You have to plan to make sure that by the time you reach the distance of Mar's orbit, Mars is where you need it to be! Practically, this means that you can only begin your trip when Earth and Mars are properly lined up. This only happens every 26 months. That is, there is only one launch window every 26 months."

The trip could be shortened by burning more fuel — a process not ideal with today's technology, Patten said.

Evolving technology can help to shorten the flight. NASA's Space Launch System (SLS) will be the new workhorse for carrying upcoming missions, and potentially humans, to the red planet. SLS is currently being constructed and tested, with NASA now targeting a launch in March or April 2022 for its Artemis 1 flight, the first flight of its SLS rocket.

Robotic spacecraft could one day make the trip in only three days. Photon propulsion would rely on a powerful laser to accelerate spacecraft to velocities approaching the speed of light. Philip Lubin, a physics professor at the University of California, Santa Barbara, and his team are working on Directed Energy Propulsion for Interstellar Exploration (DEEP-IN). The method could propel a 220-lb. (100 kilograms) robotic spacecraft to Mars in only three days, he said.

"There are recent advances which take this from science fiction to science reality," Lubin said at the 2015 NASA Innovative Advanced Concepts (NIAC) fall symposium . "There's no known reason why we cannot do this." 

How long did past missions take to reach Mars?

Here is an infographic detailing how long it took several historical missions to reach the Red Planet (either orbiting or landing on the surface). Their launch dates are included for perspective. 

Explore NASA's lunar exploration plans with their Moon to Mars overview . You can read about how to get people from Earth to Mars and safely back again with this informative article on The Conversation . Curious about the human health risks of a mission to the Red Planet? You may find this research paper of particular interest.  

Bibliography

• Lubin, Philip. " A roadmap to interstellar flight. " arXiv preprint arXiv:1604.01356 (2016). 
• Donahue, Ben B. " Future Missions for the NASA Space Launch System. " AIAA Propulsion and Energy 2021 Forum . 2021. 
• Srinivas, Susheela. " Hop, Skip and Jump—The Moon to Mars Mission. " (2019). 

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Nola Taylor Tillman is a contributing writer for Space.com. She loves all things space and astronomy-related, and enjoys the opportunity to learn more. She has a Bachelor’s degree in English and Astrophysics from Agnes Scott college and served as an intern at Sky & Telescope magazine. In her free time, she homeschools her four children. Follow her on Twitter at @NolaTRedd

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NASA’s Curiosity Rover Accidentally Discovers Sulfur Crystals on Mars

The rover’s wheel cracked open a rock and revealed pure elemental sulfur, which researchers have never seen on the Red Planet before

Eli Wizevich

As NASA’s Curiosity rover rolled across the Martian terrain this spring, its wheels inadvertently cracked a rock below. The crushed material revealed yellow crystals of sulfur in its pure elemental form—a first-ever discovery on Mars.

The accidental find, which was caused by the heft of the car-sized, one-ton rover on the morning of May 30, came as a pleasant surprise to researchers. In addition to the crystals that Curiosity drove over, the rover identified a plain with similar rocks dotting the surrounding ground.

“Finding a field of stones made of pure sulfur is like finding an oasis in the desert,” says Ashwin Vasavada , lead researcher at NASA’s Jet Propulsion Laboratory, in a statement .

*Cronch* I ran over a rock and found crystals inside! It's pure sulfur. (And no, it doesn’t smell.) Elemental sulfur is something we’ve never seen before on Mars. We don't know much about these yellow crystals yet, but my team is excited to investigate. https://t.co/Am07DuXpPX pic.twitter.com/coIqWWGGJq — Curiosity Rover (@MarsCuriosity) July 18, 2024

Since October 2022, Curiosity has been off-roading in a “ sulfate-bearing unit ” of the Red Planet on a Denali-sized peak called Mount Sharp . There, the rover has discovered minerals that contain sulfur mixed with other elements—such as magnesium sulfate and calcium sulfate. These salts, which form as water evaporates, might reveal more about the presence—and disappearance—of bodies of water on Mars billions of years ago.

But the rover had not uncovered pure sulfur until now. Its latest find occurred in the Gediz Vallis channel, a groove on the side of Mount Sharp that could also contain clues to Mars’ hydraulic history, as it likely formed by flowing water and sediment. Scientists had been eager for Curiosity to explore this area.

“My jaw dropped when I saw the image of the sulfur,” Briony Horgan , a planetary science researcher at Purdue University and a member of other rover missions, tells CNN ’s Ashley Strickland.

“Pure elemental sulfur is a very weird finding, because on Earth we mostly find it in places like hydrothermal vents,” Horgan adds. “Think Yellowstone! So, it’s a big mystery to me as to how this rock formed in Mt. Sharp.”

The newly discovered sulfur crystals were too delicate for the rover to drill into, but it did collect a sample of nearby bedrock for analysis.

Accidental-yet-crucial discoveries by Mars rovers are not unprecedented. When the Spirit rover broke one of its six wheels in 2006, it ended up driving another half mile, all the while scraping up a white powder that researchers determined to be nearly pure silica .

“It showed that there were once hot springs or steam vents at the Spirit site, which could have provided favorable conditions for microbial life,” Steve Squyres , a researcher at Cornell University and the principal investigator for the Spirit rover mission, said in a statement when the rover retired in 2011.

Since landing on Mars in 2012, the Curiosity rover has climbed 2,600 feet on Mount Sharp, which lies in the center of Gale Crater —a wide, ancient lakebed—and contains layer upon layer of sedimentary rock. Because sedimentary rock tends to form at the bottom of bodies of water, not atop mountains, NASA researchers have debated whether Mount Sharp, officially known as Aeolis Mons, formed after the erosion of marine sediment or the accumulation of wind-blown sediment in the center of the crater.

Gravity measurements from Curiosity in 2019 suggested both of these ideas might be right, in part: The data revealed the surface of Mount Sharp was less dense than expected and might have accumulated both wind-blown and lake sediments at various points.

Starting in March , the rover’s investigations in the two-mile-long Gediz Vallis channel support this conclusion. It has found both rounded rocks, which seem to have been deposited by water flows, as well as angular rocks that could have come from dry avalanches.

“This was not a quiet period on Mars,” Becky Williams , a researcher with the Planetary Science Institute who uses Curiosity’s Mastcam to study the history of water on Mars, says in NASA’s statement. “There was an exciting amount of activity here. We’re looking at multiple flows down the channel, including energetic floods and boulder-rich flows.”

The accidental discovery of elemental sulfur here, which only forms in certain circumstances that scientists have not previously associated with this part of Mars, only adds to this dynamic picture of Mount Sharp.

“It shouldn’t be there, so now we have to explain it,” Vasavada says in the statement. “Discovering strange and unexpected things is what makes planetary exploration so exciting.”

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Eli Wizevich is a reporting intern for Smithsonian . He studied history at the University of Chicago and previously wrote for the El Paso Times .

UPDATED: 10 Things for Mars 10

Scientists from around the world are gathering this week in California to take stock of the state of science from Mars and discuss goals for the next steps in exploration of the Red Planet. In the spirit of Mars 10, formally known as the 10 th International Conference on Mars , here are 10 recent significant events that got scientists talking:

DISCOVERY ALERT: A Fascinating Mars Rock

July 25, 2024: NASA's Perseverance rover, the six-wheeled geologist exploring Mars, found a fascinating rock that has some indications it may have hosted microbial life billions of years ago, but further research is needed.

• " NASA’s Perseverance Rover Scientists Find Intriguing Mars Rock "

1. An International Science Fleet at Mars

July 2024: Nine spacecraft are now operating at Mars – two surface rovers and seven orbiters. NASA’s fleet includes the Perseverance and Curiosity rovers, and orbiters MAVEN , Mars Reconnaissance Orbiter , and Mars Odyssey .  ESA (European Space Agency) operates Mars Express and the ExoMars Trace Gas Orbiter . Both China and the United Arab Emirates also have spacecraft studying Mars from orbit.

• Mars Relay Network: Interplanetary Internet

2. Curiosity Discovers Mysterious Surge in Methane – Which Then Vanishes

June 2019 : NASA’s Curiosity Mars rover found a surprising result: the largest amount of methane ever measured during the mission. “The methane mystery continues,” said Ashwin Vasavada, Curiosity’s project scientist. “We’re more motivated than ever to keep measuring and put our brains together to figure out how methane behaves in the Martian atmosphere.”

• “ Curiosity’s Mars Methane Mystery Continues ”

3. Curiosity Discovers Evidence of Ancient Wave Ripples From a Lake Bottom

February 2023 : NASA’s Curiosity rover team was surprised to discover the mission’s clearest evidence yet of ancient water ripples that formed within lakes in an area they expected to be much drier.

• “ NASA’s Curiosity Finds Surprise Clues to Mars’ Watery Past ”

4. InSight Detects First Quake on Another Planet

April 2019 : NASA's Mars InSight lander measured and recorded for the first time ever a "marsquake." "InSight's first readings carry on the science that began with NASA's Apollo missions," said InSight Principal Investigator Bruce Banerdt. "We've been collecting background noise up until now, but this first event officially kicks off a new field: Martian seismology!"

• “ NASA’s InSight Detects First Likely ‘Quake’ on Mars ”

5. InSight Provides First View of Mars’ Deep Interior

July 2021 : NASA’s InSight spacecraft’s seismometer revealed details about the planet’s deep interior for the first time, including confirmation that the planet’s center is molten.

• “ NASA’s InSight Reveals the Deep Interior of Mars ”

6. InSight Finds Stunning Impact on Mars – and Ice

October 2022 : NASA’s InSight felt the ground shake during the impact while cameras aboard the Mars Reconnaissance Orbiter spotted the yawning new crater surrounded by boulder-sized chunks of ice from space.

• “ NASA’s InSight Lander Detects Stunning Meteoroid Impact on Mars ”

7. Opportunity Rover Comes to an End After Nearly 15 Years

July 2021 : One of the most successful and enduring feats of interplanetary exploration, NASA's Opportunity rover mission ended after almost 15 years exploring the surface of Mars and helping lay the groundwork for NASA's return to the Red Planet.

• “ NASA’s Opportunity Rover Mission on Mars Comes to End ”

8. Massive Dust Storm Spreads Across Mars

July 2018 : For scientists watching the Red Planet from NASA’s orbiters, summer 2018 was a windfall. “Global” dust storms, where a runaway series of storms create a dust cloud so large they envelop the planet, only appear every six to eight years (that’s 3-4 Mars years). In June 2018, one of these dust events rapidly engulfed the planet. Scientists first observed a smaller-scale dust storm on May 30. By June 20, it had gone global.

• “’ Storm Chasers’ on Mars Searching for Dusty Secrets”

9. NASA Maps Water Ice on Mars for Use by Future Astronauts

October 2023 : The map could help the agency decide where the first astronauts to the Red Planet should land. The more available water, the less missions will need to bring.

• “ NASA Is Locating Ice on Mars With This New Map ”

10. Mars Reconnaissance Orbiter Images Used to Make Massive Interactive Globe of Mars

April 2023 : Cliffsides, impact craters, and dust devil tracks are captured in mesmerizing detail in a new mosaic of the Red Planet composed of 110,000 images from NASA’s Mars Reconnaissance Orbiter (MRO).

• “ New Interactive Mosaic Uses NASA Imagery to Show Mars in Vivid Detail ”
• The 10 th Annual International Conference on Mars
• NASA’s Mars Exploration Science Goals
• NASA Mars Missions

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NASA Did Not Say It Found Life on Mars. But It’s Very Excited About This Rock.

The rock, studied by NASA’s Perseverance rover, has been closely analyzed by scientists on Earth who say that nonmicrobial processes could also explain its features.

By Kenneth Chang

Kenneth Chang has reported on the Perseverance mission since before it launched , and on other hints of possible life on Mars.

Scientists working with NASA’s Perseverance rover state emphatically that they are not claiming to have discovered life on Mars.

But many would regard a rock that the rover just finished studying as “Most Likely to Contain Fossilized Microbial Martians.” The rover has drilled and stashed a piece of the rock, which scientists hope can be brought back to Earth in the coming years for closer analysis and more definitive answers.

“What we are saying is that we have a potential biosignature on Mars,” said Kathryn Stack Morgan, the mission’s deputy project scientist. She describes a biosignature as a structure, composition or texture in a rock that could have a biological origin.

The rock, which scientists named Cheyava Falls, possesses features that are reminiscent of what microbes might have left behind when this area was warm and wet several billion years ago, part of an ancient river delta . The scientists clarified that they did not spot anything that they thought might be actual fossilized organisms.

Scientists have wondered if life could have arisen on early Mars when it possessed a dense atmosphere and flowing water. Martian rocks could hold important clues.

The Cheyava Falls find “is, for me at least, the most compelling rock that we have collected so far,” said Kenneth Farley, the mission’s project scientist and a professor of geochemistry at the California Institute of Technology. If the rock could be brought to Earth for study, he added, “it has the potential to really get at the question” of whether life ever existed on Mars.

Within the rock, Perseverance’s instruments detected organic compounds, which would provide the building blocks for life as we know it. The rover also found veins of calcium sulfate — mineral deposits that appear to have been deposited by flowing water. Liquid water is another key ingredient for life.

Perseverance also spotted small off-white splotches, about a millimeter in size, that have black rings around them, like miniature leopard spots. The black rings contain iron phosphate.

The chemical reactions that created the leopard spots could also have provided energy for microbes to live on.

Dr. Farley said that analogous features can be seen in Red Rock Canyon outside of Las Vegas.

The rocks there are made of strikingly red sandstone, stained by oxidized iron — basically, rust. But, within the red rocks, parts have been bleached white when water containing organic compounds flowed through, and the oxidized iron underwent chemical reactions with the organic molecules.

“The reason you get that white is, you just reacted away to pigment,” Dr. Farley said. “I think it’s very likely this same kind of reaction occurring in our leopard spots.”

Organic compounds — molecules that contain carbon and hydrogen — are often but not always the calling card of life. They can also be created by geological process like hydrothermal events that have no connection with life, and the complex structure within the Cheyava Falls rock could have many possible explanations.

With the limited capability of the robotic rover’s instruments, the Perseverance scientists cannot say anything more conclusive.

But one of the key parts of Perseverance’s mission is to drill samples of interesting rocks for a future mission to bring samples back to Earth for scientists to study with state-of-the-art instruments in their laboratories.

“I think this sample comes to the top of the list,” Dr. Stack Morgan said.

The Mars sample return mission , however, has hit major developmental and cost snags, putting it years behind schedule and billions of dollars over budget.

“The bottom line is that $11 billion is too expensive,” Bill Nelson, the NASA administrator, said in April. “And not returning samples until 2040 is unacceptably too long.”

Space agency officials announced that they were seeking to solicit ideas from outside companies on how to bring rocks back sooner, at a lower cost. NASA later awarded contracts to seven companies to study the problem. NASA centers are also working on three studies of their own.

What NASA decides to do about the sample return mission will affect the future of Perseverance’s explorations. “We’re all in the same holding pattern waiting to see what might transpire,” Dr. Farley said.

Much depends on how the samples will be transferred to the sample return spacecraft. One possibility is for Perseverance to simply drop them somewhere, and the next mission will go pick them up. But if Perseverance is to bring the samples to the return spacecraft, rather than have the samples collected by another robotic vehicle, then the mission managers will need to plan how to make that drive. For now, scientists have plans for the next year and a half that Perseverance will undertake regardless — to drive out of the crater, known as Jezero, that the rover is exploring, and onto the rim.

Cheyava Falls, which Perseverance started studying last month, was one of the last stops along the riverbed.

For the names of the rocks, the Perseverance team pulled together a list of national parks and preserves from around the world. “We happen to be in the Grand Canyon,” Dr. Stack Morgan said. “And Cheyava Falls is the highest waterfall in the Grand Canyon.”

Cheyava is the Hopi word for “intermittent waters,” “which turns out to be incredibly appropriate” for a river channel, now dry, on Mars, Dr. Stack Morgan said.

Although the landing site for Perseverance at Jezero crater was selected because a riverbed was thought to be the most likely place to preserve signs of ancient life, more than three years of exploration have passed without uncovering any compelling biosignatures.

Dr. Farley said that the lack of biosignatures did not mean the mission had been a disappointment until now. The variety of rocks that have been collected have the potential to answer a wide variety of geological puzzles on Mars.

“Looking for evidence of past life is a really important goal,” he said. “But it’s also a goal that, let’s just call it, high risk, high reward.”

Leaving the riverbed does not mean leaving the search for past life behind. The impact that carved out the Jezero crater likely created hydrothermal systems along the rim of the crater, which might have provided habitable environments for life.

Kenneth Chang, a science reporter at The Times, covers NASA and the solar system, and research closer to Earth. More about Kenneth Chang

What’s Up in Space and Astronomy

Keep track of things going on in our solar system and all around the universe..

Never miss an eclipse, a meteor shower, a rocket launch or any other 2024 event  that’s out of this world with  our space and astronomy calendar .

Astronomers said they had identified the earliest, most distant galaxy yet found : a banana-shaped blob of color measuring 1,600 light-years across.

The company SpaceX achieved a key set of ambitious goals  on the fourth test flight of a vehicle that is central to Elon Musk’s vision of sending people to Mars.

Euclid, a European Space Agency telescope launched into space last summer, finally showed off what it’s capable of with a batch of breathtaking images  and early science results.

A dramatic blast from the sun  set off the highest-level geomagnetic storm in Earth’s atmosphere, making the northern lights visible around the world .

Is Pluto a planet? And what is a planet, anyway? Test your knowledge here .

We Might Get Thrilling News About Aliens … in 2040

The search for extraterrestrial life starts with an interesting-looking rock. Bringing it back to Earth is the hard part.

Yesterday, NASA announced that one of its Mars rovers had sampled a very, very intriguing rock. At first glance, the rock looks much like the rest of the red planet—rugged, sepia-toned, dry. But it’s arguably the most exciting one that robotic space explorers have ever come across. The rock, NASA said in a press release, “possesses qualities that fit the definition of a possible indicator of ancient life.”

Of course it would happen like this. In the midst of a historically eventful summer—an attempted assassination of a former president, the abrupt campaign exit of a sitting one, possibly the worst IT failure in history—scientists might have an alien discovery on their hands.

To be clear, the rock, which scientists are calling Cheyava Falls, bears only potential evidence of fossilized life. There are other plausible explanations for its appearance and composition, mundane ones that have nothing to do with biological processes. Still, scientists are thrilled. “This is the exact type of rock that we came to Mars to find,” Briony Horgan, a planetary scientist at Purdue University who led the selection of the mission’s destination, told me. But to really investigate whether Cheyava Falls contains marvelous, existential proof of another genesis in our very own solar system, NASA needs to bring the sample home—a prospect that might take more than 15 years.

Read: We’ve never seen Mars quite like this

According to NASA, the rover, called Perseverance, has detected in Cheyava Falls organic compounds, which are necessary for life as we know it. The rock bears dozens of leopard spots: tiny, irregularly shaped off-white splotches, ringed with black material that NASA scientists say contains iron and phosphate. Such features can arise from chemical reactions that could provide life-giving energy for microbes. If you encountered these leopard spots in an ancient rock formation on Earth, you would assume that some microscopic organisms once dwelled there.

The Cheyava Falls rock was found in a region of Mars’s Jezero Crater that many scientists believe flowed with water several billion years ago. Perhaps, before the planet froze over, there might have been enough time—and the right ingredients—for tiny life forms to emerge; if so, Jezero Crater could have been among the liveliest spots on the red planet. Cheyava Falls supports that theory because it is marked with streaks of calcium sulfate, which suggests that water once flowed through its sediments. Crucially, sulfate is good for preserving organic material, Horgan said.

Scientists inside and outside NASA know that the discovery comes with caveats. Carol Stoker, a NASA planetary scientist who is not involved in the mission, told me in an email that although “this is the most interesting rock that Perseverance has sampled,” she would like to see more evidence for the claim that the rover’s instruments detected organic materials. Entirely abiotic processes can produce organic compounds. And just because certain chemical components could serve as energy sources, that doesn’t mean that something once used them. “That’s like saying that a field of corn is evidence for the presence of cows,” Darby Dyar, a planetary geologist at Mount Holyoke College who has studied interactions between minerals and microbes, told me in an email.

Read: Scientists are very worried about NASA’s Mars plan

More evidence isn’t likely to come anytime soon. NASA says that the Perseverance has studied the Cheyava Falls rock “from just about every angle imaginable,” with every instrument it’s got. But the rover alone can’t tell scientists if the discovery signals a true breakthrough. “The only way to be sure is to get that sample into a lab on Earth,” Paul Byrne, a planetary scientist at Washington University in St. Louis, told me in an email.

The good news is that NASA has spent years working on an ambitious mission, called Mars Sample Return, to do just that. The bad news is that the mission is currently in limbo . NASA officials put development on pause earlier this year, saying that the program had become too expensive and was taking too long. The working timeline meant that the samples that Perseverance has been collecting wouldn’t return to Earth until 2040, and even before the Cheyava Falls discovery, NASA wanted them back sooner. The agency is now considering alternative mission concepts, including bringing home fewer samples than planned. That possibility has worried scientists, and they’re no doubt hoping that the tantalizing finding persuades NASA not to give up on the mission. If nothing else, the timing of this discovery is convenient for proponents of sample return, an extra point of data in favor of bringing as many samples home as soon as possible.

Read: Mars’s soundscape is strangely beautiful

Scientists are used to ambiguity in this line of work. Back in September 2020, in the throes of the coronavirus pandemic, scientists announced that they had found evidence of phosphine in the clouds of Venus—a gas that, on Earth, is associated with life. (Apparently there’s never a nice, quiet time to announce the discovery of maybe-aliens.) Almost four years later, scientists remain unsure about whether the phosphine is a product of living creatures, ordinary geological activity, or something else. To our knowledge, Venus remains lifeless.

Even if Cheyava Falls is brought to Earth, scientists might not come to any meaningful conclusions. They might not find anything because, as intriguing as Cheyava Falls looks now, Perseverance’s drill might have struck just to the left or the right of fossilized life, and none of it would have made it into the sample tube. Martian life might even be hidden in another part of the planet altogether, at its frigid poles or in underground caves. Or scientists could find nothing because they don’t know what to look for; their search is guided by the structure of life as we know it on Earth, and they may not recognize what our planetary neighbor has managed to create.

Short of the arrival of giant spaceships from an extraterrestrial civilization eager to bestow on us a new language, uncovering maybe-aliens in the form of teeny, long-dead microbes won’t change the course of most people’s daily lives. But the finding would still be a source of wonder, even comfort. It would mean that the history of life on Earth is just one story, perhaps one of countless others in the universe. A pale red dot, suspended in the same sunbeam as our blue one , with its own rich tale of movement and community. But until scientists can actually examine Cheyava Falls and other samples like it, we don’t have a hope of understanding how those stories might have begun.

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How Rocks Get Their Spots

Another puzzle piece, more mission information, news media contacts.

The six-wheeled geologist found a fascinating rock that has some indications it may have hosted microbial life billions of years ago, but further research is needed.

A vein-filled rock is catching the eye of the science team of NASA’s Perseverance rover. Nicknamed “Cheyava Falls” by the team, the arrowhead-shaped rock contains fascinating traits that may bear on the question of whether Mars was home to microscopic life in the distant past.

Analysis by instruments aboard the rover indicates the rock possesses qualities that fit the definition of a possible indicator of ancient life. The rock exhibits chemical signatures and structures that could possibly have been formed by life billions of years ago when the area being explored by the rover contained running water. Other explanations for the observed features are being considered by the science team, and future research steps will be required to determine whether ancient life is a valid explanation.

The rock — the rover’s 22nd rock core sample — was collected on July 21, as the rover explored the northern edge of Neretva Vallis, an ancient river valley measuring a quarter-mile (400 meters) wide that was carved by water rushing into Jezero Crater long ago.

“We have designed the route for Perseverance to ensure that it goes to areas with the potential for interesting scientific samples,” said Nicola Fox, associate administrator, Science Mission Directorate at NASA Headquarters in Washington. “This trip through the Neretva Vallis riverbed paid off as we found something we’ve never seen before, which will give our scientists so much to study.”

Multiple scans of Cheyava Falls by the rover’s SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) instrument indicate it contains organic compounds. While such carbon-based molecules are considered the building blocks of life, they also can be formed by non-biological processes.

“Cheyava Falls is the most puzzling, complex, and potentially important rock yet investigated by Perseverance,” said Ken Farley,Perseverance project scientist of Caltech in Pasadena. “On the one hand, we have our first compelling detection of organic material, distinctive colorful spots indicative of chemical reactions that microbial life could use as an energy source, and clear evidence that water — necessary for life — once passed through the rock. On the other hand, we have been unable to determine exactly how the rock formed and to what extent nearby rocks may have heated Cheyava Falls and contributed to these features.”

Other details about the rock, which measures 3.2 feet by 2 feet (1 meter by 0.6 meters) and was named after a Grand Canyon waterfall, have intrigued the team, as well.

In its search for signs of ancient microbial life, the Perseverance mission has focused on rocks that may have been created or modified long ago by the presence of water. That’s why the team homed in on Cheyava Falls.

“This is the kind of key observation that SHERLOC was built for — to seek organic matter as it is an essential component of a search for past life,” said SHERLOC’s principal investigator Kevin Hand of NASA’s Jet Propulsion Laboratory in Southern California, which manages the mission.

Running the length of the rock are large white calcium sulfate veins. Between those veins are bands of material whose reddish color suggests the presence of hematite, one of the minerals that gives Mars its distinctive rusty hue.

When Perseverance took a closer look at these red regions, it found dozens of irregularly shaped, millimeter-size off-white splotches, each ringed with black material, akin to leopard spots. Perseverance’s PIXL (Planetary Instrument for X-ray Lithochemistry) instrument has determined these black halos contain both iron and phosphate.

“These spots are a big surprise,” said David Flannery, an astrobiologist and member of the Perseverance science team from the Queensland University of Technology in Australia. “On Earth, these types of features in rocks are often associated with the fossilized record of microbes living in the subsurface.”

Spotting of this type on sedimentary terrestrial rocks can occur when chemical reactions involving hematite turn the rock from red to white. Those reactions can also release iron and phosphate, possibly causing the black halos to form. Reactions of this type can be an energy source for microbes, explaining the association between such features and microbes in a terrestrial setting.

In one scenario the Perseverance science team is considering, Cheyava Falls was initially deposited as mud with organic compounds mixed in that eventually cemented into rock. Later, a second episode of fluid flow penetrated fissures in the rock, enabling mineral deposits that created the large white calcium sulfate veins seen today and resulting in the spots.

While both the organic matter and the leopard spots are of great interest, they aren’t the only aspects of the Cheyava Falls rock confounding the science team. They were surprised to find that these veins are filled with millimeter-size crystals of olivine, a mineral that forms from magma. The olivine might be related to rocks that were formed farther up the rim of the river valley and that may have been produced by crystallization of magma.

If so, the team has another question to answer: Could the olivine and sulfate have been introduced to the rock at uninhabitably high temperatures, creating an abiotic chemical reaction that resulted in the leopard spots?

“We have zapped that rock with lasers and X-rays and imaged it literally day and night from just about every angle imaginable,” said Farley. “Scientifically, Perseverance has nothing more to give. To fully understand what really happened in that Martian river valley at Jezero Crater billions of years ago, we’d want to bring the Cheyava Falls sample back to Earth, so it can be studied with the powerful instruments available in laboratories.”

A key objective of Perseverance’s mission on Mars is astrobiology , including caching samples that may contain signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, to help pave the way for human exploration of the Red Planet and as the first mission to collect and cache Martian rock and regolith.

NASA’s Mars Sample Return Program, in cooperation with ESA (European Space Agency), is designed to 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.

NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech, built and manages operations of the Perseverance rover.

For more about Perseverance:

science.nasa.gov/mission/mars-2020-perseverance

DC Agle Jet Propulsion Laboratory, Pasadena, Calif. 818-393-9011 [email protected]

Karen Fox / Erin Morton Headquarters, Washington 202-358-1600 / 202-805-9393 [email protected] / [email protected]

Related Terms

• Perseverance (Rover)
• Astrobiology
• Mars Sample Return (MSR)

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