ExoMars captures spring in martian craters

ESA & ROSCOSMOS - ExoMars Mission patch.

August 6, 2020

ExoMars Trace Gas Orbiter (TGO)

A new set of images captured this spring by the Colour and Stereo Surface Imaging System (CaSSIS) on the ESA-Roscosmos ExoMars Trace Gas Orbiter shows a series of interesting geological features on the surface of Mars, captured just as the planet passed its spring equinox.

Dune fields in the Green Crater of Mars

Dune fields in Mars' Green Crater

The image above, taken on 27 April 2020 and centred at 52.3°S, 351.8°E, shows part of an impact crater located inside the larger Green Crater in the Argyre quadrangle in the southern hemisphere of Mars.

The image reveals an almost black dune field on the right surrounded by red soils, partially covered with bright white ice. Gullies, also partially covered with ice, are visible in the crater wall in the centre of the image. Scientists are currently investigating the relationship between this seasonal ice and the presence of the gullies. The image was taken just after the spring equinox in the southern hemisphere of Mars, when the southernmost part of the crater (to the right) was almost completely free of ice while the northern part (centre) was still partially covered. The southern crater wall has had a longer exposure to the Sun (like on Earth, equator-facing slopes receive more sunlight), so the ice in this area has receded faster.

Leaf-like structures in Antoniadi impact crater

Leaf-like structures in Antoniadi impact crater

This image, captured on 25 March 2020, shows the bottom of the 400 km in diameter Antoniadi impact crater, which is located in the northern hemisphere of Mars in the Syrtis Major Planum region. The blue colour of the image, centred at 21.0°N, 61.2°E, does not represent the real colour of the crater floor but highlights the diversity of the rock composition inside this impact crater.

In the centre of the image are dendritic structures which look like the veins on oak leaves. These structures, evidence of ancient river networks in this region, protrude from the surface, unlike channels, which are usually sunken in the surface. This is because the channels were filled with harder material – possibly lava – and over time the softer rocks surrounding these branching channels have been eroded, leaving an inverted imprint of this ancient river system.

Argyre impact basin after spring equinox

Argyre impact basin after spring equinox

This image of the Argyre impact basin in the southern highlands of Mars was taken on 28 April 2020 just as Mars had passed its southern hemisphere spring equinox. The seasonal ice in the 800km-long impact basin is visibly receding while the ridge on the right side of the image is still covered with frost. The image is centred at 57.5°S, 310.2°E. The frost-covered ridge is facing the pole, therefore receiving less solar radiation than the neighbouring equator-facing slope. On Mars, incoming solar radiation transforms the ice into water vapour directly without melting it first into water in a process called sublimation. Since the north-facing slope (on the left) has had a longer exposure to solar radiation, its ice has sublimated more quickly.

Rock composition in Ius Chasma canyon

Rock composition in Ius Chasma canyon

The image taken on 5 May 2020 shows a part of the floor of the Ius Chasma canyon, part of the Valles Marines system of canyons that stretches nearly a quarter of the circumference of Mars south of the planet's equator. The Ius Chasma canyon, which can be seen in the image rising up to a ridge on the right side, is about 1000 km long and up to 8 km deep, which makes it more than twice as long and four times as deep as the famous Grand Canyon in the US state of Arizona. The centre of this image is located at 8.8°S, 282.5°E.

The beautiful colour variations across the floor of Ius Chasma are caused by changes in rock composition. Scientists theorise that the light rocks are salts left behind after an ancient lake evaporated. The information about the rock's composition is useful to scientists as it allows them to retrace the formation history of the canyon.

Related links:

ExoMars: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Exploration/ExoMars

Trace Gas Orbiter (TGO): https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Exploration/ExoMars/Trace_Gas_Orbiter_instruments

ExoMars/TGO operations: https://www.esa.int/Enabling_Support/Operations/ExoMars_TGO_operations

Images, Text, Credits: ESA/ExoMars/CaSSIS.

Best regards, Orbiter.ch

Weightless action on the Space Station – power, bones and bubbles

ISS - International Space Station logo.

August 6, 2020

European science progressed at a slower pace on the International Space Station in the past month. As a series of spacewalks to power up the space habitat came to an end and two of its passengers left for home Earth, intriguing bubbles puzzled researchers and left them wanting to know more.

The sun beams during a spacewalk

The longest foam

More bubbles, please. The Space Station has witnessed the longest science run with foams for the Foam-Coarsening experiment. This research mixed varying amounts of water and soap inside small tubes for 14 days in a row. A high-speed piston shook the mixture for two minutes, followed by 100 hours of recording with laser optics, photon counters and high-resolution cameras to achieve the best science.

The result? The foam bubbles become larger, last longer and their motion is very different from what you would expect on Earth. In space, bubble sizes are evenly spread and that makes it easier for scientists to study them in greater detail.

In some cases, scientists detected an anomalous behaviour in the foam – a hole appeared just in the middle of the bubbles. The team decided to follow up this unexpected phenomenon, and extended the foaming time to up to 20 minutes in some of the tubes.

Foam-Coarsening experiment

The foaming process slows down over time and it is stopped after two weeks, or when there are only five bubbles left inside the tubes. Scientists call it the “five bubble criteria” – this approach helps them estimate when to finish the measurements.

A foam’s existence in space is marked by more equilibrium than on Earth because drainage is suppressed. Foams have huge benefits for our daily lives – they are lighter, offer better insulation and can be just as strong as compact materials.

So, maybe think outside your bubble next time you look at a foam, be it in your beer, cream or shaving gel.

Foams. We research. You benefit.

Bones and stress

Roscosmos’ Anatoly Ivanishin and Ivan Vagner took part in the second session of EDOS-2 and Immuno-2 experiments as test subjects.

Astronauts lose up to 1% of their bone mass each month they stay in space. Studying what happens during long stays on the Space Station offers a good insight into this form of accelerated osteoporosis, and how to stop it in patients on Earth as well.

The Early Detection of Osteoporosis in Space experiment, or EDOS-2, is looking at changes in bone structure before and after spaceflight. Researchers study markers in blood and urine in a dozen of astronauts, as well as through a tomography scan.

Dinner time for the Expedition 63 crew

Scientists aim to better understand bone loss in space and find rehabilitation techniques not only for astronauts, but also for the thousands of patients on Earth suffering from bone diseases or fractures during ageing.

The way the body responds to stress as it adapts to the challenging environment of space is also under investigation. Through brain scans, monitoring breathing and looking at samples from hair and blood, researchers of the the Immuno-2 experiment hope to learn more about how living in stressful conditions affect immune systems.

More power and new ‘kids’ on the block

The International Space Station’s power system is heavily dependent on its batteries. The month of July saw the power spacewalk series to increase the Station’s efficiency drawing to a close.

NASA astronauts Chris Cassidy and Bob Behnken performed the 11th spacewalk in a three-and-a-half-year effort to upgrade the International Space Station’s power system.

Chris Cassidy works during a spacewalk

Less is more, and the replacement programme cut down the old 48 nickel-hydrogen batteries to 24 lithium-ion new ones.

A new visiting vehicle had some issues approaching the Station on 23 July. Russia launched its second unpiloted mission of the year, the 76th Progress mission, to deliver cargo to the Space Station.

Progress MS-15 spacecraft approaches Space Station

The Progress MS-15 spacecraft deviated from the flight plan momentarily but there was no need to hit the abort button. The automated docking was successful, and the spacecraft arrived safely about three hours after launch loaded with over two tonnes of water, oxygen, fuel, experiment payloads and food.

After 62 days on the Space Station, the first crewed test flight came to an end. NASA astronauts Robert Behnken and Douglas Hurley spent more than 100 hours supporting science and technology demonstrations at their space home.

Just over 45 years since the last North Americans splashed down in the ocean, the two astronauts landed in the Gulf of Mexico on 2 August.

Related links:

Foam-Coarsening experiment: http://www.esa.int/ESA_Multimedia/Images/2020/03/Foam-Coarsening_experiment#.XrOqgqm84og.link

EDOS-2: http://blogs.esa.int/iriss/2015/11/17/edos-early-detection-of-osteoporosis-in-space/

Immuno-2: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Research/Stressed_in_space

Human and Robotic Exploration: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration

Images, Video, Text, Credits: ESA/NASA.

Best regards, Orbiter.ch

Rare phenomenon observed by ATLAS features the LHC as a high-energy photon collider

CERN - European Organization for Nuclear Research logo.

5 August, 2020

The ATLAS experiment reports the observation of photon collisions producing weak-force carriers and provides further insights into their interactions. 

Image above: A 2018 ATLAS event display consistent with the production of a pair of W bosons from two photons, and the subsequent decay of the W bosons into a muon and an electron (visible in the detector) and neutrinos (not detected). (Image: CERN).

During the International Conference on High-Energy Physics (ICHEP 2020), the ATLAS collaboration presented the first observation of photon collisions producing pairs of W bosons, elementary particles that carry the weak force, one of the four fundamental forces. The result demonstrates a new way of using the LHC, namely as a high-energy photon collider directly probing electroweak interactions. It confirms one of the main predictions of electroweak theory – that force carriers can interact with themselves – and provides new ways to probe it.

According to the laws of classical electrodynamics, two intersecting light beams would not deflect, absorb or disrupt one another. However, effects of quantum electrodynamics (QED), the theory that explains how light and matter interact, allow interactions among photons.

Indeed, it is not the first time that photons interacting at high energies have been studied at the LHC. For instance, light-by-light “scattering”, where a pair of photons interact by producing another pair of photons, is one of the oldest predictions of QED. The first direct evidence of light-by-light scattering was reported by ATLAS in 2017, exploiting the strong electromagnetic fields surrounding lead ions in high-energy lead–lead collisions. In 2019 and 2020, ATLAS further studied this process by measuring its properties.

The new result reported at this conference is sensitive to another rare phenomenon in which two photons interact to produce two W bosons of opposite electric charge via (among others) the interaction of four force carriers[1]. Quasi-real photons from the proton beams scatter off one another to produce a pair of W bosons. A first study of this phenomenon was previously reported by ATLAS and CMS in 2016, from data recorded during LHC Run 1, but a larger dataset was required to unambiguously observe it.

The observation was obtained with a highly significant statistical evidence of 8.4 standard deviations, corresponding to a negligible chance of being due to a statistical fluctuation. ATLAS physicists used a considerably larger dataset taken during Run 2, the four-year data collection in the LHC that ended in 2018, and developed a customised analysis method.

Large Hadron Collider (LHC). Animation Credit: CERN

Owing to the nature of the interaction process, the only particle tracks visible in the central detector are the decay products of the two W bosons, an electron and a muon with opposite electric charge. W-boson pairs can also be directly produced from interactions between quarks and gluons in the colliding protons considerably more often than from photon–photon interactions, but these are accompanied by additional tracks from strong interaction processes. This means that the ATLAS physicists had to carefully disentangle collision tracks to observe this rare phenomenon.  

"This observation opens up a new facet of experimental exploration at the LHC using photons in the initial state”, said Karl Jakobs, spokesperson of the ATLAS collaboration. “It is unique as it only involves couplings among electroweak force carriers in the strong-interaction-dominated environment of the LHC. With larger future datasets it can be used to probe in a clean way the electroweak gauge structure and possible contributions of new physics."

Indeed, the new result confirms one of the main predictions of electroweak theory, namely that, besides interacting with ordinary particles of matter, the force carriers, also known as gauge bosons – the W bosons, the Z boson and the photon – are also interacting with each other. Photon collisions will provide a new way to test the Standard Model and to probe for new physics, which is necessary for a better understanding of our Universe.

[1] The four force-carrier interaction is one of the predictions of the electroweak theory that explains how force-carrier particles, also known as gauge bosons, interact not only with matter particles, but also with one another.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 23 Member States.

Links, related articles & scientific material:

- ICHEP 2020: https://ichep2020.org/

- Observation of photon-induced W+W− production in proton–proton collisions at 13 TeV using the ATLAS detector: https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2020-038/ATLAS-CONF-2020-038.pdf

- ATLAS Physics briefing on the result: https://atlas.cern/updates/physics-briefing/observation-w-pair-from-light

- Scientific Plots and Diagrams: https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2020-038/

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Image (mentioned), Animation (mentioned), Text, Credit: CERN.

Best regards, Orbiter.ch

Satellite "Kanopus-V" captured the consequences of the explosion in the port of Beirut

ROSCOSMOS logo.

August 5, 2020

The Russian satellite for remote sensing of the Earth "Kanopus-V" captured the consequences of an explosion in the port of Beirut (Lebanon). A powerful explosion occurred on August 4, 2020 in the area of ​​the seaport of Beirut near the naval base. The presented photographs clearly show the nature of the destruction on the embankment near the explosion site: a number of buildings were demolished by the shock wave. The photo also shows the epicenter of the explosion.

According to local authorities, the cause of the tragedy was the detonation of 2,700 tons of ammonium nitrate confiscated by customs services, which were stored in the warehouse.

Comparative images of the harbor of Beirut before and after the explosion

 

Beirut harbor after the explosion

The Kanopus-V space complex is used as part of the Roskosmos Earth remote sensing orbital constellation, designed to obtain panchromatic and multispectral images of the Earth's surface in the interests of providing units of the Roskosmos State Corporation, EMERCOM of Russia, the Ministry of Natural Resources and Ecology of the Russian Federation, and the Federal Service for Hydrometeorology and monitoring of the environment of Russia, the Russian Academy of Sciences, as well as other departments and commercial consumers with operational information.

Beirut harbor explosion blast seen from sea

VNIIEM Corporation is the head organization-developer of the Kanopus-V spacecraft. The operator of the space system is the Scientific Center for Operational Monitoring of the Earth "Russian Space Systems". The flight control of spacecraft is carried out by the Flight Control Center of TsNIIMash.

Kanopus-V satellite

The intended use of the space complex "Kanopus-V" is carried out in accordance with the applications of consumers for obtaining information from remote sensing of the Earth. Reception, processing and distribution of satellite information is carried out by the centers of Roscosmos and Roshydromet. The information received from the satellite is in demand by Russian and foreign consumers and is used to solve practical problems.

ROSCOSMOS Press Release: https://www.roscosmos.ru/28938/

Images, Animation, Text, Credits: ROSCOSMOS/AFP/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

Space Research, Orbital Plumbing Fill Crew’s Day

ISS - Expedition 63 Mission patch.

August 5, 2020

The Expedition 63 crew, with one U.S. astronaut and two Russian cosmonauts aboard the International Space Station, juggled an array of space research and orbital plumbing duties on Wednesday.

Commander Chris Cassidy ran several test operations today of the Water Droplet Formation experiment that may improve fluid management on spaceships and faucets and showers on Earth. The veteran astronaut also analyzed water samples for microbes and checked on biology and robotics hardware.

Image above: Expedition 63 Commander Chris Cassidy services microbial DNA samples for sequencing and identification aboard the space station’s Harmony module. Image Credits: NASA.

Cassidy then switched roles from space scientist to high-flying plumber and serviced the station’s restroom, the Waste and Hygiene Compartment, located in the Tranquility module. He also exchanged water recovery system pumps inside Japan’s Kibo laboratory module.

Flight Engineer Anatoly Ivanishin of Roscosmos spent Wednesday morning working on power and electrical systems in the orbiting lab’s Russian segment. The experienced cosmonaut then moved onto fluid transfers into the Progress 76 resupply ship then studied ways improve to interactions between mission controllers and space crews.

 International Space Station (ISS). Animation Credit: NASA

Cosmonaut Ivan Vagner from Roscosmos started the morning communicating with students on Earth using a ham radio. The first-time space flyer then worked the rest of the day on a variety of maintenance tasks including replacing pumps and checking smoke detectors.

Related links:

Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html

Water Droplet Formation: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7541

Biology: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=329

Robotics: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1891

Tranquility module: https://www.nasa.gov/mission_pages/station/structure/elements/tranquility/

Kibo laboratory module: https://www.nasa.gov/mission_pages/station/structure/elements/japan-kibo-laboratory

Communicating with students: https://www.energia.ru/en/iss/researches/popular/07.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

'Shallow Lightning' and 'Mushballs' Reveal Ammonia to NASA's Juno Scientists

NASA - JUNO Mission patch.

Aug. 5, 2020

New results from NASA's Juno mission at Jupiter suggest our solar system's largest planet is home to what's called "shallow lightning." An unexpected form of electrical discharge, shallow lightning originates from clouds containing an ammonia-water solution, whereas lightning on Earth originates from water clouds.

Other new findings suggest the violent thunderstorms for which the gas giant is known may form slushy ammonia-rich hailstones Juno's science team calls "mushballs"; they theorize that mushballs essentially kidnap ammonia and water in the upper atmosphere and carry them into the depths of Jupiter's atmosphere.

Image above: This illustration uses data obtained by NASA's Juno mission to depict high-altitude electrical storms on Jupiter. Juno's sensitive Stellar Reference Unit camera detected unusual lightning flashes on Jupiter's dark side during the spacecraft's close flybys of the planet. Image Credits: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Heidi N. Becker/Koji Kuramura.

The shallow-lightning findings will be published Thursday, Aug. 6, in the journal Nature, while the mushballs research is currently available online in the Journal of Geophysical Research: Planets.

Since NASA's Voyager mission first saw Jovian lightning flashes in 1979, it has been thought that the planet's lightning is similar to Earth's, occurring only in thunderstorms where water exists in all its phases – ice, liquid, and gas. At Jupiter this would place the storms around 28 to 40 miles (45 to 65 kilometers) below the visible clouds, with temperatures that hover around 32 degrees Fahrenheit (0 degrees Celsius, the temperature at which water freezes). Voyager saw lightning as bright spots on Jupiter's cloud tops, suggesting that the flashes originated in deep water clouds. But lightning flashes observed on Jupiter's dark side by Juno's Stellar Reference Unit tell a different story.

"Juno's close flybys of the cloud tops allowed us to see something surprising – smaller, shallower flashes – originating at much higher altitudes in Jupiter's atmosphere than previously assumed possible," said Heidi Becker, Juno's Radiation Monitoring Investigation lead at NASA's Jet Propulsion Laboratory in Southern California and the lead author of the Nature paper.

Becker and her team suggest that Jupiter's powerful thunderstorms fling water-ice crystals high up into the planet's atmosphere, over 16 miles (25 kilometers) above Jupiter's water clouds, where they encounter atmospheric ammonia vapor that melts the ice, forming a new ammonia-water solution. At such lofty altitude, temperatures are below minus 126 degrees Fahrenheit (minus 88 degrees Celsius) – too cold for pure liquid water to exist.

"At these altitudes, the ammonia acts like an antifreeze, lowering the melting point of water ice and allowing the formation of a cloud with ammonia-water liquid," said Becker. "In this new state, falling droplets of ammonia-water liquid can collide with the upgoing water-ice crystals and electrify the clouds. This was a big surprise, as ammonia-water clouds do not exist on Earth."

Image above: In the center of this JunoCam image, small, bright "pop-up" clouds seen rise above the surrounding features. Clouds like these are thought to be the tops of violent thunderstorms responsible for shallow lighting. Image Credits: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill © CC BY.

The shallow lightning factors into another puzzle about the inner workings of Jupiter's atmosphere: Juno's Microwave Radiometer instrument discovered that ammonia was depleted – which is to say, missing – from most of Jupiter's atmosphere. Even more puzzling was that the amount of ammonia changes as one moves within Jupiter's atmosphere.

"Previously, scientists realized there were small pockets of missing ammonia, but no one realized how deep these pockets went or that they covered most of Jupiter," said Scott Bolton, Juno's principal investigator at the Southwest Research Institute in San Antonio. "We were struggling to explain the ammonia depletion with ammonia-water rain alone, but the rain couldn't go deep enough to match the observations. I realized a solid, like a hailstone, might go deeper and take up more ammonia. When Heidi discovered shallow lightning, we realized we had evidence that ammonia mixes with water high in the atmosphere, and thus the lightning was a key piece of the puzzle."

Jovian Mushballs

A second paper, released yesterday in the Journal of Geophysical Research: Planets, envisions the strange brew of 2/3 water and 1/3 ammonia gas that becomes the seed for Jovian hailstones, known as mushballs. Consisting of layers of water-ammonia slush and ice covered by a thicker water-ice crust, mushballs are generated in a similar manner as hail is on Earth – by growing larger as they move up and down through the atmosphere.

"Eventually, the mushballs get so big, even the updrafts can't hold them, and they fall deeper into the atmosphere, encountering even warmer temperatures, where they eventually evaporate completely," said Tristan Guillot, a Juno co-investigator from the Université Côte d'Azur in Nice, France, and lead author of the second paper. "Their action drags ammonia and water down to deep levels in the planet's atmosphere. That explains why we don't see much of it in these places with Juno's Microwave Radiometer."

Image above: This graphic depicts the evolutionary process of “shallow lightning” and "mushballs" on Jupiter. Image Credits: NASA/JPL-Caltech/SwRI/CNRS.

"Combining these two results was critical to solving the mystery of Jupiter's missing ammonia," said Bolton. "As it turned out, the ammonia isn't actually missing; it is just transported down while in disguise, having cloaked itself by mixing with water. The solution is very simple and elegant with this theory: When the water and ammonia are in a liquid state, they are invisible to us until they reach a depth where they evaporate – and that is quite deep."

Understanding the meteorology of Jupiter enables us to develop theories of atmospheric dynamics for all the planets in our solar system as well as for the exoplanets being discovered outside our solar system. Comparing how violent storms and atmospheric physics work across the solar system allows planetary scientists to test theories under different conditions.

More About the Mission

The solar-powered Jupiter explorer launched nine years ago today, on Aug. 5, 2011. And last month marked the fourth anniversary of its arrival at Jupiter. Since entering the gas giant's orbit, Juno has performed 27 science flybys and logged over 300 million miles (483 million kilometers).

Juno spacecraft orbiting Jupiter. Animation Credit: NASA

JPL, a division of Caltech in Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for the agency's Science Mission Directorate in Washington. Lockheed Martin Space in Denver built and operates the spacecraft.

More information about Juno is available at:

https://www.nasa.gov/juno

https://www.missionjuno.swri.edu

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Tony Greicius/Alana Johnson/Grey Hautaluoma/JPL/DC Agle/Southwest Research Institute/Deb Schmid/French National Centre for Scientific Research/François Maginiot.

Best regards, Orbiter.ch

Rocket Sees Curling Waves Above Alaskan Sky

NASA Goddard Space Flight Center (GSFC) logo.

Aug. 5, 2020

Animation above: Trimethyl-aluminum gas clouds released by the first of three rockets launched as part of the Super Soaker campaign. The curling waves of the Kelvin-Helmholtz instability – appearing briefly in the center of the image before dissipating – may explain how gases mix in what were previously considered stable layers of the atmosphere. Image Credits: NASA/Super Soaker/Rafael Mesquita.

The “surfer waves” in this image, forming high above the Alaskan sky, illuminate the invisible currents in the upper atmosphere. They were measured by trimethyl-aluminum gas released during a sounding rocket launch from Poker Flat, Alaska, on Jan. 26, 2018. Scientists photograph the gas, which is not harmful to humans, after it instantaneously ignites when exposed to oxygen. The findings were published in JGR: Space Physics.

NASA Sounding Rocket Program. Image Credit: NASA

Such curling waves are a product of the Kelvin-Helmholtz instability, which occurs when streams of gas or liquid pass by each other at different speeds. As the streams grate against one another, they produce characteristic curls that appear all over in nature, from the ocean’s surface to the swirling dust along Jupiter’s belt.

Researchers from Clemson University in South Carolina observed the Kelvin-Helmholtz instability shown here some 65 miles above Earth. As the waves dissipated, they created turbulence, mixing the gases above and below them. This turbulent sloshing within an otherwise stable layer of the atmosphere shows one way gases move up and down in our atmosphere. It could explain why molecular nitrogen, which is heavy, is sometimes observed much higher than it should be, while lighter atomic oxygen somehow sinks below.

Image above: The flight profile of a sounding rocket in its parabolic trajectory -- it goes up and comes back down. In this short flight time and lower altitude regions of space that are too low to be sampled by satellites are accessible. Image Credit: NASA.

Understanding how winds move through the atmosphere contributes an extra puzzle piece to the entire atmospheric system – where a slight temperature imbalance at the equator can ultimately lead to huge gusts of wind high above the arctic.

Related links:

JGR - Space Physics: https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JA027972

Sounding Rockets: http://www.nasa.gov/mission_pages/sounding-rockets/index.html

Images (mentioned), Animation (mentioned), Text, Credits: NASA/GSFC/By Miles Hatfield.

Greetings, Orbiter.ch