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Tonga eruption’s towering plume reached the 3rd layer of Earth’s atmosphere

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CNN
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When the Hunga Tonga-Hunga Ha’apai volcano erupted underwater in January, it created a plume of ash and water that broke through the third layer of Earth’s atmosphere.

It was the highest-recorded volcanic plume and reached the mesosphere, where meteors and meteorites usually break apart and burn up in our atmosphere.

The mesosphere, about 31 to 50 miles (50 to 80 kilometers) above Earth’s surface, is above the troposphere and stratosphere and beneath two other layers. (The stratosphere and mesosphere are dry atmospheric layers.)

The volcanic plume reached an altitude of 35.4 miles (57 kilometers) at its highest. It exceeded previous record holders such as the 1991 Mount Pinatubo eruption in the Philippines at 24.8 miles (40 kilometers) and the 1982 El Chichón eruption in Mexico, which reached 19.2 miles (31 kilometers).

Researchers used images captured by satellites passing over the eruption site to confirm the plume’s height. The eruption occurred January 15 in the southern Pacific Ocean off the Tongan archipelago, an area covered by three geostationary weather satellites.

A study detailing the findings published Thursday in the journal Science.

The towering plume sent into the upper layers of the atmosphere contained enough water to fill 58,000 Olympic-size swimming pools, according to previous detections from a NASA satellite.

Understanding the height of the plume can help researchers study the impact the eruption might have on the global climate.

Determining the plume’s height posed a challenge to researchers. Typically, scientists can measure the altitude of a plume by studying its temperature — the colder a plume, the higher it is, said lead study coauthor Dr. Simon Proud of RAL Space and a research fellow at the National Centre for Earth Observation and the University of Oxford.

But this method couldn’t be applied to the Tonga event due to the violent nature of its eruption.

“The eruption pushed through the layer of atmosphere we live in, the troposphere, into the upper layers where the atmosphere warms up again as you get higher,” said Proud via email.

“We had to come up with another approach, using the different views given by weather satellites located on opposite sides of the Pacific and some pattern matching techniques to work out the altitude. This has only become possible in recent years, as even ten years ago we didn’t have the satellite technology in space to do this.”

The research team relied on “the parallax effect” to determine the plume’s height, comparing the difference in appearance of the plume from multiple angles as captured by the weather satellites. The satellites took images every 10 minutes, documenting the dramatic changes in the plume as it rose out of the ocean. The images reflected differences in the plume’s position from varying lines of sight.

The eruption “went from nothing to a 57 kilometer-high tower of ash and cloud in 30 minutes,” Proud said. Members of the team also noticed rapid changes in the top of the eruptive plume that surprised them.

“After the initial big burst to 57 kilometers, the central dome of the plume collapsed inward, before another plume appeared shortly after,” Proud said. “I hadn’t expected something like that to occur.”

The amount of water the volcano released into the atmosphere is expected to warm the planet temporarily.

“This technique not only allows us to determine the maximum height of the plume but also the various levels in the atmosphere where volcanic material was released,” said study coauthor Dr. Andrew Prata, a postdoctoral research assistant in the Clarendon Laboratory’s sub-department of atmospheric, oceanic and planetary physics at the University of Oxford, via email.

Knowing the composition and height of the plume can reveal how much ice was sent into the stratosphere and where ash particles were released.

The height is also critical for aviation safety because volcanic ash can cause jet engine failure, so avoiding ash plumes is key.

The plume height is yet another emerging detail of what has become known as one of the most powerful volcanic eruptions recorded. When the undersea volcano erupted 40 miles (65 kilometers) north of Tonga’s capital, it triggered a tsunami as well as shock waves that rippled around the world.

Research is ongoing to unlock why the eruption was so powerful, but it might be because it occurred underwater.

The heat of the eruption vaporized the water and “created a steam explosion much more powerful than a volcanic eruption would normally be,” Proud said.

“Examples like the Hunga Tonga-Hunga Ha’apai eruption demonstrate that magma-seawater interactions play a significant role in producing highly explosive eruptions that can inject volcanic material to extreme altitudes,” Prata added.

Next, the researchers want to understand why the plume was so high as well as its composition and ongoing impact on the global climate.

“Often when people think of volcanic plumes they think of volcanic ash,” Prata said. “However, preliminary work on this case is revealing that there was a significant proportion of ice in the plume. We also know that there was a fairly modest amount of sulfur dioxide and sulfate aerosols formed rapidly after the eruption took place.”

Proud wants to use the multi-satellite altitude technique in this study to create automatic warnings for severe storms and volcanic eruptions.

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Venus-bound NASA instrument prepping to brave harsh atmosphere

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NASA scientists are preparing to paint the most detailed picture to date of the atmosphere of Venus when the aptly named DAVINCI — or Deep Atmosphere Venus Investigation of Noble Gases, Chemistry, and Imaging — mission drops a probe to the planet’s surface.

When the 3-foot-wide (0.9 meters) descent sphere of the DAVINCI mission takes its one-way parachute trip to Venus‘ surface in the early 2030s, it will be carrying the VASI (Venus Atmospheric Structure Investigation) instrument along with five other instruments. VASI will collect data regarding the temperature, pressure and winds of Venus’ atmosphere as it makes its hellish descent and enters the planet’s crushing lower atmosphere. 

“There are actually some big puzzles about the deep atmosphere of Venus,” Ralph Lorenz, the science lead for the VASI instrument and a planetary scientist at the Johns Hopkins Applied Physics Laboratory (APL) in Maryland, said in a statement. “We don’t have all the pieces of that puzzle and DAVINCI will give us those pieces by measuring the composition at the same time as the pressure and temperature as we get near the surface.”

Related: NASA’s Parker Solar Probe captures stunning Venus photo during close flyby

The dense atmosphere of Venus hides several mysteries, including how it is structured, as well as how the planet’s many volcanoes have interacted with it over the eons. One of scientists’ key goals in plunging a probe through the atmosphere of the second planet from the sun is to determine whether that world is still volcanically active. The probe could sniff this out through measurements of atmospheric temperatures, winds and composition.

Solving these puzzles could give scientists an idea of what continued volcanic activity could mean for our own planet’s atmosphere.

“The long-term habitability of our planet, as we understand it, rests on the coupling of the interior and atmosphere,” Lorenz said. “The long-term abundance of carbon dioxide in our atmosphere, which we really rely on to have kept Earth’s surface warm enough to be habitable over geologic time, relies on volcanoes.”

A one-way trip to Venus 

One of the main challenges associated with investigating Venus has been the extreme conditions of the planet, which boasts surface pressures up to 90 times greater than that of Earth and surface temperatures around 900 degrees Fahrenheit (460 degrees Celsius). 

Additionally, before any probe can reach the planet’s surface from orbit it must first pass through clouds of sulfuric acid in the upper atmosphere of Venus. (These clouds also happen to make Venus tough to observe from Earth; reflective and shiny, they obscure our view of the planet’s surface.)

These threats mean that DAVINCI’s descent sphere systems and sensors will be enclosed within a hardy, submarine-like structure. But while the sphere is built to withstand intense atmospheric pressures and is insulated to shield sensors from the intense heat near Venus’ surface, VASI’s sensors must be somewhat exposed to the harsh conditions in order to do their job.

“Venus is hard. The conditions, especially low in the atmosphere, make it very challenging to engineer the instrumentation and the systems to support the instrumentation,” Lorenz said. “All that has to be either protected from the environment or somehow built to tolerate it.”

As the sphere drops through the atmosphere of Venus, VASI will measure the temperature with a sensor within a thin, straw-like metal tube. As the atmosphere heats the tube, the sensor measures and records the expansion and thus the temperature without directly being exposed to the corrosive environment.

VASI will collect atmospheric pressure readings using a silicon membrane encased within it. One side of the membrane is exposed to a vacuum while the other side faces Venus’ atmosphere. The atmosphere pushes on the membrane, stretching it, and the extent of this stretching reveals the strength of the atmospheric pressure. 

The instrument will measure Venusian winds with a combination of accelerometers that test for changes in speed and direction and gyroscopes that measure orientation. The mission will also track changes in wind speed and direction by monitoring shifts in the frequency and wavelength of radio waves.

Named for Italian Renaissance polymath Leonardo da Vinci, DAVINCI is currently set for launch in 2029. If it stays on schedule, the descent sphere will plunge through the thick atmosphere of Venus in 2031.

The drop will take around an hour. The probe is not expected to survive the fall, but if it does, NASA scientists are prepared to get around 17 minutes of bonus science at the surface with the doomed device. 

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Science

Watch the moment a fireball smashes into Earth’s atmosphere and explodes during the Orionid meteor shower

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A camera caught a meteor glowing brightly before it slammed into the Earth’s atmosphere during the peak of the Orionid meteor shower early on Friday. 

A photographer caught an incredible sight early Friday while filming the Orionid meteor shower.

Brenda Tate was taking a timelapse when her camera captured a meteor glowing across the sky. Then the moment it hit Earth’s atmosphere, the space object broke apart over North America.

The Orionid meteor shower peaked in the early morning hours on Friday, which is likely why Tate was able to capture the meteor outside her home in Nova Scotia, Canada.

This was moments before the fireball hit Earth’s atmosphere, and broke into pieces during the Orionid meteor shower. 

(Brenda Tate & Tim Doucette via Storyful / FOX Weather)

Some of these Orionids leave behind glowing “trains” which are essentially incandescent bits of debris in the wake of the meteor. The sights can last up to several minutes, and some faster meteors could also become fireballs.

DOORBELL CAM CATCHES FIREBALL SHOOTING THROUGH SEATTLE SKY

NASA said skygazers could spot up to 15 meteors per hour, depending on where you lived.

While the Orionid meteor shower’s peak was on October 21, the Orionids will be active through November 22.

We call them shooting stars, but it’s actually meteors that create dazzling streaks of light across our night sky.

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Science

A Nearby Star Has Completely Blasted Away the Atmosphere From its Planet

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What if you placed an Earth-sized planet in a close orbit around an M-dwarf star? It’s more than an academic question since M dwarfs are the most numerous stars we know. A group of astronomers studying the planet GJ 1252b found an answer and it’s not pretty.

Since this planet is so close to its star, it receives a lot of heat. And that proximity is deadly in another way. “The pressure from the star’s radiation is immense, enough to blow a planet’s atmosphere away,” said Michelle Hill, a University of California Riverside astrophysicist and co-author of a recent paper focused on GJ 1252b. The planet lies some 65 light-years from Earth and orbits its star twice every 24 Earth hours. The heat from the star renders this world inhospitable.

Illustration of the atmosphere being blown away from a planet by a nearby star. (NASA)

This is not terribly different from Mercury in our solar system. There’s no atmosphere and the planet is alternately heated and frozen as it orbits the Sun. In fact, Earth also loses a little atmosphere to solar activity. However, volcanism and other processes release gases back into our atmosphere. Earth is lucky; planets like Mercury and GJ 1252b are not. And, that has profound implications in the search for life-friendly worlds.

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What is it about M Dwarf Stars?

There are millions and millions of M dwarf stars in our galaxy alone. They range in size from about a tenth to two-thirds of the mass of the Sun. These can be active, sending flares and outbursts through their systems. Most have at least one planet in their habitable zones and others at a variety of distances.

That’s not a great combo if you want to find life on their planets. The stellar activity that blasts away planetary atmospheres obviously also destroys any chances for life on those worlds. And, since M dwarfs are so numerous, their ubiquity may undercut the number of planets in the galaxy that actually DO support life. That’s not great news for planets like GJ 1252b.

“It’s possible this planet’s condition could be a bad sign for planets even further away from this type of star,” Hill said. “This is something we’ll learn from the James Webb Space Telescope, which will be looking at planets like these.”

Even though M dwarfs could be atmosphere killers, it’s not all doom and gloom. For example, many of the 5,000 stars in Earth’s solar neighborhood are M dwarfs. Even if a large fraction of them blast their planets into hospitability, at least 1,000 others (not all of them M dwarfs) could foster conditions suitable for life on their worlds. “If a planet is far enough away from an M dwarf, it could potentially retain an atmosphere. We cannot conclude yet that all rocky planets around these stars get reduced to Mercury’s fate,” Hill said. “I remain optimistic.”

Looking for an Atmosphere on GJ 1252b

The science behind the situation at GJ 1252b is intriguing. Astronomers used Spitzer Space Telescope data to assess the infrared radiation from the planet as a secondary eclipse blocked its light. The measurements showed that the star blasts the planet. Daytime surface temperatures range around 1227 C (2242 F). That’s hot enough to melt gold, silver, and copper.

The heat, coupled with assumed low surface pressure, led the researchers to believe there was no atmosphere there. But, let’s assume for a moment that there WAS a carbon dioxide atmosphere. That would trap heat on the surface, and maybe allow that blanket to exist for a while. However, it turns out that GJ 1252b isn’t so fortunate. “The planet could have 700 times more carbon than Earth has, and it still wouldn’t have an atmosphere. It would build up initially, but then taper off and erode away,” said Stephen Kane, UCR astrophysicist, and study co-author.

In the long run, if this study holds true across a substantial population of M dwarf stars, that’ll shift the search for habitable planets to other candidates around less-volatile stars.

For More Information

Discovery could dramatically narrow search for space creatures
GJ 1252b: A Hot Terrestrial Super-Earth with No Atmosphere
M Dwarf Stars

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Science

Bizarre blue blobs hover in Earth’s atmosphere in stunning astronaut photo. But what are they?

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This photo taken from the ISS above the South China Sea on Oct. 30 2021 shows a pair of unrelated bright blue blobs in Earth’s atmosphere. (Image credit: NASA Earth Obsrvatory)

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An astronaut onboard the International Space Station (ISS) has snapped a peculiar image of Earth from space that contains two bizarre blue blobs of light glimmering in our planet’s atmosphere. The dazzling pair may look otherworldly. But in reality, they are the result of two unrelated natural phenomena that just happened to occur at the same time.

The image was captured last year by an unnamed member of the Expedition 66 crew as the ISS passed over the South China Sea. The photo was released online Oct. 9 by NASA’s Earth Observatory (opens in new tab). 

The first blob of light, which is visible at the bottom of the image, is a massive lightning strike somewhere in the Gulf of Thailand. Lightning strikes are typically hard to see from the ISS, as they’re usually covered by clouds. But this particular strike occurred next to a large, circular gap in the top of the clouds, which caused the lightning to illuminate the surrounding walls of the cloudy caldera-like structure, creating a striking luminous ring.   

Related: Upward-shooting ‘blue jet’ lightning spotted from International Space Station 

The second blue blob, which can be seen in the top right of the image, is the result of warped light from the moon. The orientation of Earth’s natural satellite in relation to the ISS means the light it reflects back from the sun passes straight through the planet’s atmosphere, which transforms it into a bright blue blob with a fuzzy halo. This effect is caused by some of the moonlight scattering off tiny particles in Earth’s atmosphere, according to Earth Observatory.

Image 1 of 2

The first blue blob was the result of a lightning strike illuminating a large bowl of uncovered cloud in the Gulf of Thailand. (Image credit: NASA Earth Obsrvatory)

Different colors of visible light have different wavelengths, which affects their interaction with atmospheric particles. Blue light has the shortest wavelength and is therefore the most likely to scatter, which caused the moon to turn blue in this image. The same effect also explains why the sky appears blue during the daytime: because blue wavelengths of sunlight scatter the most and become more visible to the human eye, according to NASA (opens in new tab). 

Also visible in the photo is a glowing web of artificial lights coming from Thailand. The other prominent sources of light pollution in the image are emitted from Vietnam and Hainan Island, the southernmost region of China, though these light sources are largely obscured by clouds. The orange halo parallel to the curvature of the Earth is the edge of the atmosphere, which is commonly known as “Earth’s limb” when viewed from space, according to Earth Observatory. 

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Heaviest element ever found in atmosphere of exoplanets

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CNN
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Astronomers have spotted an unexpected chemical element high within the atmosphere of two sizzling exoplanets where liquid iron and gems rain down from the skies.

The two exoplanets, which orbit separate stars beyond our solar system, are ultrahot gas giants called WASP-76b and WASP-121b. Astronomers used the European Southern Observatory’s Very Large Telescope to detect barium at high altitudes in the atmosphere of each exoplanet.

Barium is the heaviest element ever discovered within the atmosphere of an exoplanet. The journal Astronomy & Astrophysics published a study detailing the discovery on Thursday.

With each revelation, WASP-76b and WASP-121b seem more strange to scientists.

“The puzzling and counterintuitive part is: why is there such a heavy element in the upper layers of the atmosphere of these planets?” said lead study author Tomás Azevedo Silva, a doctoral student at the University of Porto and the Institute of Astrophysics and Space Sciences in Portugal, in a statement.

“This was in a way an ‘accidental’ discovery. We were not expecting or looking for barium in particular and had to cross-check that this was actually coming from the planet since it had never been seen in any exoplanet before.”

Both exoplanets are similar in size to Jupiter, the largest planet in our solar system, but they have incredibly hot surface temperatures well above 1,832 degrees Fahrenheit (1,000 degrees Celsius).

The soaring temperatures on WASP-76b and WASP-121b stem from the fact that each planet is located close to its host star, completing a single orbit in about one or two days.

First discovered in 2015, WASP-121b is about 855 light-years from Earth. The exoplanet has a glowing water vapor atmosphere, and the intense gravitational pull of the star it orbits is deforming it into the shape of a football.

The planet is tidally locked, meaning the same side of the planet always faces the star. This is similar to how our moon orbits Earth. On the dayside, temperatures begin at 4,040 F (2,227 C) at the deepest layer of the atmosphere and reach 5,840 F (3,227 C) at the top layer.

Scientists spotted WASP-76b for the first time in 2016. It orbits a star in the Pisces constellation 640 light-years away from Earth. This exoplanet is also tidally locked, so on its dayside, which faces the star, temperatures exceed 4,400 F (2,426 C).

The sizzling nature of the exoplanets has given them unusual features and weather that seem like something out of science fiction. Scientists think liquid iron rains from the sky on WASP-76b, while metal clouds and liquid gems form on WASP-121b.

Detecting barium in the upper atmosphere of each planet surprised researchers. The element is 2 1/2 times heavier than iron.

“Given the high gravity of the planets, we would expect heavy elements like barium to quickly fall into the lower layers of the atmosphere,” said study coauthor Olivier Demangeon, a postdoctoral researcher at the University of Porto and the Institute of Astrophysics and Space Sciences in Portugal, in a statement.

Finding barium in the atmosphere of both exoplanets might suggest that ultrahot gas giants have even more unusual features than suspected.

On Earth, barium appears in the night skies as a vibrant green color when fireworks are set off. But scientists aren’t sure what natural process is causing the heavy element to appear so high in the atmosphere of these gas giants.

The research team used the ESPRESSO instrument, or Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations, installed in the Very Large Telescope in Chile, to study starlight as it passed through the atmosphere of each planet.

“Being gaseous and hot, their atmospheres are very extended,” Demangeon said, “and are thus easier to observe and study than those of smaller or cooler planets.”

Future telescopes will also be able to spy more details within the atmospheric layers of exoplanets, including rocky ones similar to Earth, to unlock the mysteries of unusual worlds across the galaxy.

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Science

A Planet-Sized Heatwave Has Been Found in Jupiter’s Atmosphere : ScienceAlert

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A heatwave the size of 10 Earths has been discovered rippling through Jupiter’s atmosphere.

It was 130,000 kilometers (around 81,000 miles) across, and a scorching 700 degrees Celsius (1,292 degrees Fahrenheit), traveling at speeds up to 2,400 meters per second away from the Jovian north pole.

And this, scientists say, could resolve one of the more perplexing mysteries about our Solar System’s biggest planet – why it’s so much hotter than models predict.

It’s the permanent auroras that glimmer at Jupiter’s poles that could be providing the extra energy to heat the gas giant to temperatures way beyond what we expect – and likely, along with a dense solar wind, responsible for the billowing heatwave.

“Last year we produced … the first maps of Jupiter’s upper atmosphere capable of identifying the dominant heat sources,” says astronomer James O’Donoghue of the Japan Aerospace Exploration Agency (JAXA) in Japan.

“Thanks to these maps, we demonstrated that Jupiter’s auroras were a possible mechanism that could explain these temperatures.”

The first inkling that there was something hinky going on in Jupiter’s atmosphere came in the 1970s, around 50 years ago.

Jupiter is much farther from the Sun than Earth; roughly five times the distance, in fact. At that distance, it receives just four percent of the solar radiation that reaches Earth.

Its upper atmosphere should have an average temperature of around -73 degrees Celsius (-99 degrees Fahrenheit). Instead, it sits at around 420 degrees Celsius – comparable to Earth’s upper atmosphere, and way higher than can be accounted for by solar heating alone.

This means that there must be something else going on at Jupiter, and the first heat maps, obtained by O’Donoghue and his colleagues and published last year, pointed to a solution.

Jupiter is crowned by the most powerful auroras in the Solar System, blazing in wavelengths invisible to the human eye. We also know that auroras here on Earth cause not-insignificant heating of our own atmosphere.

Jupiter’s auroras form a lot like Earth’s: an interaction between charged particles, magnetic fields, and molecules in the planet’s atmosphere. And they’re also very alien, too. Earth’s auroras are born from gusts of particles blown in on powerful solar winds. They’re sporadic, reliant on that irregular input.

Jupiter’s auroras are permanent, generated by particles from its moon Io, the most volcanic object in the Solar System, which is constantly belching sulfur dioxide. This forms a torus of plasma around Jupiter, which is channeled to its poles via magnetic field lines, where it rains into the atmosphere.

Et voilà – aurora. The prior heat maps of Jupiter revealed hotspots directly below the auroral oval, suggesting a connection between the two.

But then it got more interesting. The contribution of Io doesn’t mean that there is no auroral contribution from the Sun, and this is what O’Donoghue and his colleagues observed.

As they were collecting observations of Jupiter and its strange temperatures, a dense solar wind slammed into the gas giant. As a result, the team observed an enhancement to the auroral heating.

frameborder=”0″ allow=”accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture” allowfullscreen>

Because hot gas expands, this is probably what sent the heat wave spilling out of the auroral oval and rolling down towards the equator at speeds up to thousands of kilometers per hour.

So, as it propagated, this would have delivered a significant amount of additional heat to the Jovian atmosphere.

“While the auroras continuously deliver heat to the rest of the planet, these heat wave ‘events’ represent an additional, significant energy source,” O’Donoghue explains.

“These findings add to our knowledge of Jupiter’s upper-atmospheric weather and climate, and are a great help in trying to solve the ‘energy crisis’ problem that plagues research into the giant planets.”

Jupiter is not the only planet in the Solar System that is hotter than it should be. Saturn, Neptune, and Uranus are all hundreds of degrees hotter than solar heating can account for.

While none of the others have auroras on the scale of Jupiter’s, this finding represents an avenue for exploration that may go some way towards solving the puzzle.

The team presented their findings at the Europlanet Science Congress 2022.

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New clues about early atmosphere on Mars suggest a wet planet capable of supporting life

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A 3D render of a blue wet planet. Credit: Planet Volumes/Anodé on Unsplash

New research published in Earth and Planetary Science Letters suggests that Mars was born wet, with a dense atmosphere allowing warm-to-hot oceans for millions of years. To reach this conclusion, researchers developed the first model of the evolution of the Martian atmosphere that links the high temperatures associated with Mars’s formation in a molten state through to the formation of the first oceans and atmosphere.

This model shows that—as on the modern Earth—water vapor in the Martian atmosphere was concentrated in the lower atmosphere and that the upper atmosphere of Mars was “dry” because the water vapor would condense out as clouds at lower levels in the atmosphere. Molecular hydrogen (H2), by contrast, did not condense and was transported to the upper atmosphere of Mars, where it was lost to space. This conclusion—that water vapor condensed and was retained on early Mars whereas molecular hydrogen did not condense and escaped—allows the model to be linked directly to measurements made by spacecraft, specifically, the Mars Science Laboratory rover Curiosity.

“We believe we have modeled an overlooked chapter in Mars’s earliest history in the time immediately after the planet formed. To explain the data, the primordial Martian atmosphere must have been very dense (more than ~1000x as dense as the modern atmosphere) and composed primarily of molecular hydrogen (H2),” said Kaveh Pahlevan, SETI Institute research scientist.

“This finding is significant because H2 is known to be a strong greenhouse gas in dense environments. This dense atmosphere would have produced a strong greenhouse effect, allowing very early warm-to-hot water oceans to be stable on the Martian surface for millions of years until the H2 was gradually lost to space. For this reason, we infer that—at a time before the Earth itself had formed—Mars was born wet.”

The data constraining the model is the deuterium-to-hydrogen (D/H) ratio (deuterium is the heavy isotope of hydrogen) of different Martian samples, including Martian meteorites and those analyzed by Curiosity. Meteorites from Mars are mostly igneous rocks—they formed when the interior of Mars melted, and the magma ascended towards the surface. The water dissolved in these interior (mantle-derived) igneous samples has a deuterium-to-hydrogen ratio similar to that of the Earth’s oceans, indicating that the two planets started with similar D/H ratios and that their water came from the same source in the early solar system.

By contrast, Curiosity measured the D/H ratio of an ancient 3-billion-year-old clay on the Martian surface and found that this value is ~3x that of Earth’s oceans. Apparently, by the time these ancient clays formed, the surface water reservoir on Mars—the hydrosphere—had substantially concentrated deuterium relative to hydrogen. The only process known to produce this level of deuterium concentration (or “enrichment”) is preferential loss of the lighter H isotope to space.

The model further shows that if the Martian atmosphere was H2-rich at the time of its formation (and more than ~1000x as dense as today), then the surface waters would naturally be enriched in deuterium by a factor of 2–3x relative to the interior, reproducing the observations. Deuterium prefers partitioning into the water molecule relative to molecular hydrogen (H2), which preferentially takes up ordinary hydrogen and escapes from the top of the atmosphere.

“This is the first published model that naturally reproduces these data, giving us some confidence that the atmospheric evolutionary scenario we have described corresponds to early events on Mars,” said Pahlevan.

Aside from curiosity about the earliest environments on the planets, H2-rich atmospheres are significant in the SETI Institute’s search for life beyond Earth. Experiments going back to the middle of the 20th century show that prebiotic molecules implicated in the origin of life form readily in such H2-rich atmospheres but not so readily in H2-poor (or more “oxidizing”) atmospheres. The implication is that early Mars was a warm version of modern Titan and at least as promising a site for the origin of life as early Earth was, if not more promising.

Help NASA scientists find clouds on Mars

More information:
Kaveh Pahlevan et al, A primordial atmospheric origin of hydrospheric deuterium enrichment on Mars, Earth and Planetary Science Letters (2022). DOI: 10.1016/j.epsl.2022.117772
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New clues about early atmosphere on Mars suggest a wet planet capable of supporting life (2022, September 21)
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James Webb Space Telescope’s first pictures of Mars could reveal more about the atmosphere

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The James Webb Space Telescope is still snapping its first pictures of Solar System planets, and the latest batch could be particularly useful. NASA and the ESA have shared early images of Mars, taken on September 5th, that promise new insights into the planet’s atmosphere. Data from the near-infrared camera (NIRCam) is already offering a few surprises. For starters, the giant Hellas Basin is oddly darker than nearby areas at the hottest time of the day, NASA’s Giuliano Liuzzi and Space.com noted — higher air pressure at the basin’s lower altitude has suppressed thermal emissions.

The JWST imagery also gave space agencies an opportunity to share Mars’ near-infrared atmospheric composition using the telescope’s onboard spectrograph array. The spectroscopic ‘map’ (pictured at middle) shows the planet absorbing carbon dioxide at several different wavelengths, and also shows the presences of carbon monoxide and water. A future research paper will provide more detail about the Martian air’s chemistry.

NASA, ESA, CSA, STScI, Mars JWST/GTO team

It was particularly tricky to record the images. Mars is one of the brightest objects the James Webb telescope can see — a problem for an observatory designed to study the most distant objects in the universe. Researchers countered this by capturing very short exposures and using special techniques to analyze the findings.

This is only the initial wave of pictures and data. It will take more observations to reveal more about Mars. However, the spectral info already hints at more information about the planet’s materials. Liuzzi also thinks JWST studies could settle disputes over the presence of methane on Mars, potentially signalling that the Red Planet harbored life in its distant past.

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James Webb Space Telescope’s first pictures of Mars could reveal more about the atmosphere

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The James Webb Space Telescope is still snapping its first pictures of Solar System planets, and the latest batch could be particularly useful. NASA and the ESA have shared early images of Mars, taken on September 5th, that promise new insights into the planet’s atmosphere. Data from the near-infrared camera (NIRCam) is already offering a few surprises. For starters, the giant Hellas Basin is oddly darker than nearby areas at the hottest time of the day, NASA’s Giuliano Liuzzi and Space.com noted — higher air pressure at the basin’s lower altitude has suppressed thermal emissions.

The JWST imagery also gave space agencies an opportunity to share Mars’ near-infrared atmospheric composition using the telescope’s onboard spectrograph array. The spectroscopic ‘map’ (pictured at middle) shows the planet absorbing carbon dioxide at several different wavelengths, and also shows the presences of carbon monoxide and water. A future research paper will provide more detail about the Martian air’s chemistry.

NASA, ESA, CSA, STScI, Mars JWST/GTO team

It was particularly tricky to record the images. Mars is one of the brightest objects the James Webb telescope can see — a problem for an observatory designed to study the most distant objects in the universe. Researchers countered this by capturing very short exposures and using special techniques to analyze the findings.

This is only the initial wave of pictures and data. It will take more observations to reveal more about Mars. However, the spectral info already hints at more information about the planet’s materials. Liuzzi also thinks JWST studies could settle disputes over the presence of methane on Mars, potentially signalling that the Red Planet harbored life in its distant past.

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