Escape From Mars: Surprising Discovery in the Red Planet’s Atmosphere Helps Explain Martian Mystery

NASA's MAVEN Reveals Most of Mars' Atmosphere Was Lost to Space

This artist’s concept depicts the early Martian environment (right) – believed to contain liquid water and a thicker atmosphere – versus the cold, dry environment seen on Mars today (left). Credit: NASA’s Goddard Space Flight Center

New University of Arizona-led research updates our understanding of how water escapes Mars — not like a leaky faucet but with a sudden splash.

Mars once had oceans but is now bone-dry, leaving many to wonder how the water was lost. University of Arizona researchers have discovered a surprisingly large amount of water in the upper atmosphere of Mars, where it is rapidly destroyed, explaining part of this Martian mystery.

Shane Stone, a graduate student in the UArizona Lunar and Planetary Laboratory and lead author of a new paper to be published in Science, describes himself as a planetary chemist. Once a laboratory chemist who helped to develop polymers that could be used to wrap and deliver therapeutic drugs more efficiently, he now studies the chemistry of planetary atmospheres.

Since 2014, he has worked on NASA’s MAVEN mission, short for Mars Atmosphere and Volatile Evolution. The MAVEN spacecraft began orbiting Mars in 2014 and has been recording the composition of the upper atmosphere of Earth’s planetary neighbor ever since.

“We know that billions of years ago, there was liquid water on the surface of Mars,” Stone said. “There must have been a thicker atmosphere, so we know that Mars somehow lost the majority of its atmosphere to space. MAVEN is trying to characterize the processes responsible for this loss, and one portion of that is understanding exactly how Mars lost its water.”

Co-authors of the study include Roger Yelle, a UArizona planetary sciences professor and Stone’s research adviser, as well as researchers from NASA Goddard Space Flight Center and the Center for Research and Exploration in Space Science and Technology in Maryland.

Watching for Water

As MAVEN orbits Mars, it dips into the planet’s atmosphere every 4 1/2 hours. The onboard NGIMS instrument – short for Neutral Gas and Ion Mass Spectrometer – has been measuring the abundance of charged water molecules called ions in the upper Martian atmosphere, about 100 miles (160 kilometers) from the planet’s surface. From this information, scientists can infer how much water is present in the atmosphere.

Past observations using MAVEN and the Hubble Space Telescope showed that loss of water from the Martian upper atmosphere varies with the seasons. Compared to Earth, Mars takes a more oval-shaped path around the sun and is closest to it during summer in the Martian southern hemisphere.

Stone and his team found that when Mars is nearest the sun, the planet warms, and more water – found on the surface in the form of ice – moves from the surface to the upper atmosphere where it is lost to space. This happens once every Martian year or about every two Earth years. The regional dust storms that occur on Mars every Martian year and the global dust storms that occur across the planet about once every 10 years lead to further heating of the atmosphere and a surge in the upward movement of water.

The processes that make this cyclical movement possible contradict the classical picture of water escape from Mars, showing it is incomplete, Stone said. According to the classical process, ice formed from water is converted to a gas and is destroyed by the sun’s rays in the lower atmosphere. This process, however, would play out as a slow, steady trickle, unaffected by the seasons or dust storms, which doesn’t mesh with current observations.

“This is important because we didn’t expect to see any water in the upper atmosphere of Mars at all,” Stone said. “If we compare Mars to Earth, water on Earth is confined close to the surface because of something called the hygropause. It’s just a layer in the atmosphere that’s cold enough to condense (and therefore stop) any water vapor traveling upward.”

The team argues that water is moving past what should be Mars’ hygropause, which is likely too warm to stop the water vapor. Once in the upper atmosphere, water molecules are broken apart by ions very quickly – within four hours, they calculate – and the byproducts are then lost to space.

“The loss of its atmosphere and water to space is a major reason Mars is cold and dry compared to warm and wet Earth. This new data from MAVEN reveals one process by which this loss is still occurring today,” Stone said.

A Dry and Dusty World

When the team extrapolated their findings back 1 billion years, they found that this process can account for the loss of a global ocean about 17 inches (43 centimeters) deep.

“If we took water and spread it evenly over the entire surface of Mars, that ocean of water lost to space due to the new process we describe would be over 17 inches deep,” Stone said. “An additional 6.7 inches (17 centimeters) would be lost due solely to the effects of global dust storms.”

During global dust storms, 20 times more water can be transported to the upper atmosphere. For example, one global dust storm lasting 45 days releases the same amount of water to space as Mars would lose during a calm Martian year, or 687 Earth days.

And while Stone and his team can’t extrapolate farther back than 1 billion years, he thinks that this process likely didn’t work the same before that, because Mars might have had a stronger hygropause long ago.

“Before the process we describe began to operate, there must have been a significant amount of atmospheric escape to space already,” Stone said. “We still need to nail down the impact of this process and when it began to operate.”

In the future, Stone would like to study the atmosphere of Saturn’s moon Titan.

“Titan has an interesting atmosphere in which organic chemistry plays a significant role,” Stone said. “As a former synthetic organic chemist, I’m eager to investigate these processes.”

Reference: “Hydrogen escape from Mars is driven by seasonal and dust storm transport of water” by Shane W. Stone, Roger V. Yelle, Mehdi Benna, Daniel Y. Lo, Meredith K. Elrod and Paul R. Mahaffy, 13 November 2020, Science.
DOI: 10.1126/science.aba5229

19 Comments on "Escape From Mars: Surprising Discovery in the Red Planet’s Atmosphere Helps Explain Martian Mystery"

  1. ET’s gathered up Mars water and rained it down on Earth to expose Gold. Elemental gold being needed for intergalactic travel. Malleability, density, reflective benefits all would make gold mining necessary for even the most advanced cultures. Once the low hanging fruit was harvested scavenger entities were planted to glean the remains of Earthly gold.

  2. Yahayabaraushuwaki | November 13, 2020 at 10:31 am | Reply

    What will say about conjunction of Saturn,Pluto in December?and changes of weather will come up within 48hours dueto Venus in it’s house and moon in Scorpio.

  3. If you try to postulate that Mars had “oceans of water” then the presence of perchlorates firmly and chemically debunks that hypothesis.
    Let’s leave that fact for a moment in time and suggest another hypothesis: IF there WERE oceans of water, and IF the planet was warmer, (due to internal temperature warming affects), then life, as we know life, was most probably there.
    Let’s keep the assumptions going: to have accumulated water, looking at today’s meager atmosphere on Mars, one would have to assume that the ability of water to form and pool on Mars was NOT affected by the same, or similar atmospheric chemistry and conditions. Or there would have been no accumulation of water at all: it would have boiled off or evaporated off minute one… never becoming “oceans.”
    So the assumption of “oceans” means the conditions needed to be there for “oceans” Day 1 and those conditions MUST have changed because, hey: there’s no oceans today.
    How do you change an atmosphere? Well the best example is Earth… where our atmosphere has undergone numerous changes that have worked to first create then protect our surface water.
    Let me make this long story short: I postulate that early life on Mars created a protective layer in their atmosphere and then, like today on Earth, later evolution of life destroyed that layer. And radiation and blab blab blab…
    My suggestion is that our “scientists” take their heads out of their corporate purchased as es and get on-board with the future we are headed towards iffin we don’t all work together and stop the global destruction by corporate greed.
    That’s where we are today folks.

    • Torbjörn Larsson | November 13, 2020 at 12:06 pm | Reply

      This was more interesting, you started out discussing the handle, but ended up in an antiscience rant which I assume is explained by your handle. You seem to think GMO, which is among the more modern and precise – less dangerous – forms of our 10 kyrs old artificial selection methods on farming, is a problem and not the solution which experts think it is. As we know from easily accessible statistics such as given by Gapminder or Our World In Numbers, the world – aside from the pandemic setback – is ever getting better, thanks in no small part to modern democracy and capitalism (“the worst of systems, except all the others”) and – science!

      Back to the science: the article does discuss changes in water loss – and how the early loss [as well as climate, not mentioned] is an open question – did you read it?

      But presence of perchlorates are not a problem for the observations that ealy Mars had water. In fact, the oxygen that went into the compounds is likely from atmosphere water under the influence of UV due to no ozone layer.

      Finally, the idea that current life has somehow destroyed a protective layer (the ozone layer has been protected and is on its way to recover, say) is somewhat ironic. How badly humans try to mess up Earth, we can never achieve the mess and atmospheric destruction that bacteria once did. When cyanobacteria oxygenated the earlier atmosphere, they drastically changed the planet forever and they killed an estimate 99 % of life – the worst mass extinction this planet has seen. And they weren’t even “greedy”, albeit their genes were selfish as any other genes, they were just ever opportunistic life.

      • Torbjörn Larsson | November 13, 2020 at 12:09 pm | Reply

        “you started out discussing the handle” – you started out discussing the science.
        “ealy Mars” – early Mars.
        “How badly humans try to mess up Earth” – However humans try to mess up Earth.

      • It’s honestly so sad how people ignore data, facts, even plain logic in order to soothe their consciences and fit their conception of science.

  4. The comments here are physically painful to read. Wow.

  5. Unless and Until we can restore Mars’ Magnetic field, there is no point in trying to “Terraform” the planet since it will continue to lose atmosphere and water and dust, etc. to the solar wind.
    If we can somehow restore that magnetic field. we’ll have a “Plan B” world as a backstop in case we keep being stupid with our homeworld.

  6. Why restore a magnetic field? Do we know if mars ever had one? Venus does not have one, or rather does not generate it’s own field, but still has a thick atmosphere.

  7. Mars had an atmosphere similar to Earth that was blown away by a nuclear explosion creating a shock wave that circled all the way around the planet. How do we know this? Easy, all the isotopes only created by nuclear fission of plutonium has been discovered on Mars. Even better, google the PDF from NASA regarding the nuclear isotopes discovered on mars.

  8. Allow me to enlighten you all that historically, statistically and most likely, you are all wrong. If one of you is right, the remaining lot of you is indeed wrong.

    Try entering the game of 100 theories of 100 men aware of this. Or wear your Dunden Kruger halo for all to see.

  9. If you want to judge facts, you need evidence. Hearsay is not evidence.

    Did you hear something from someone? Can that person or any other demonstrate? Is the answer no? Do you nevertheless build your theory on such a foundation? Do you then tell others?


    Do you truly believe that a delay in transmission time is the reason we have no proof but rather renditions? Proof would take 80hrs to transmit, so “they” decided on non-proof that takes only 8hrs? I for one am perfectly fine with real proof even if it takes 6 months to transmit. I will assume I’m not the only fellow with such patience?

    Enron Musk effect….

    Zero tenure for dissenters! “Educated idiots” with full faith in non-science, claiming to be scientists.

    You can’t see it or hear it. You can’t demonstrate it. But you believe it anyways. That’s called faith, not science!

    Here is my theory:

    If there were rovers on Mars, these rovers would be equipped with the most advanced AV capture & transmission capabilities available at the time they were manufactured. No?

  10. Dear econuts, dont judge all knowledge and all events from one way of thinking. These facts can be also from more external factors not listed or examined in this article. Example, asteroid belt is what used to be a planet. Venus being shot across the solar system that was a moon of jupiter and the some deluge water on mars is the same water on earth when the jupiter salt water moon broke apart and part hit mars and most hit earth. Just a couple to WET your knowledge base. Get it? Oh well, have a good life.

  11. Seems like what’s happening to Earth. Big things will melt because of our f***up and then evaporate because of it too. I hope I can print that word here.

  12. If we were to spread water evenly over the earth it would be about 1.7 miles (or 2.7 km) deep. 17 inches is not much of an ocean.

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