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By NASA
NASA wants you to visualize the future of space exploration! This art challenge is looking for creative, artistic images to represent NASA’s Moon to Mars Architecture, the agency’s roadmap for crewed exploration of deep space. With NASA’s Moon to Mars Objectives in hand, the agency is developing an architecture for crewed exploration of the Moon, Mars, and beyond. Using systems engineering processes, NASA has begun to perform the analyses and studies needed to make informed decisions about a sustained lunar evolution and initial human missions to Mars. NASA’s Moon to Mars Architecture currently includes four segments of increasing complexity: Human Lunar Return, Foundational Exploration, Sustained Lunar Evolution, and Humans to Mars. For this competition, NASA is interested in your artistic interpretation of the latter two segments: Sustained Lunar Evolution and Humans to Mars. These depictions could include operations in space, on the surface, or both. Artists may develop and submit a still image for either the lunar and Mars exploration segments.
Award: $10,000 in total prizes
Open Date: September 12, 2024
Close Date: October 31, 2024
For more information, visit: https://nasa.yet2.com/
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By NASA
5 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Tests on Earth appear to confirm how the Red Planet’s spider-shaped geologic formations are carved by carbon dioxide.
Spider-shaped features called araneiform terrain are found in the southern hemisphere of Mars, carved into the landscape by carbon dioxide gas. This 2009 image taken by NASA’s Mars Reconnaissance Orbiter shows several of these distinctive formations within an area three-quarters of a mile (1.2 kilometers) wide. NASA/JPL-Caltech/University of Arizona Dark splotches seen in this example of araneiform terrain captured by NASA’s Mars Reconnaissance Orbiter in 2018 are believed to be soil ejected from the surface by carbon dioxide gas plumes. A set of experiments at JPL has sought to re-create these spider-like formations in a lab. NASA/JPL-Caltech/University of Arizona Since discovering them in 2003 via images from orbiters, scientists have marveled at spider-like shapes sprawled across the southern hemisphere of Mars. No one is entirely sure how these geologic features are created. Each branched formation can stretch more than a half-mile (1 kilometer) from end to end and include hundreds of spindly “legs.” Called araneiform terrain, these features are often found in clusters, giving the surface a wrinkled appearance.
The leading theory is that the spiders are created by processes involving carbon dioxide ice, which doesn’t occur naturally on Earth. Thanks to experiments detailed in a new paper published in The Planetary Science Journal, scientists have, for the first time, re-created those formation processes in simulated Martian temperatures and air pressure.
Here’s a look inside of JPL’s DUSTIE, a wine barrel-size chamber used to simulate the temperatures and air pressure of other planets – in this case, the carbon dioxide ice found on Mars’ south pole. Experiments conducted in the chamber confirmed how Martian formations known as “spiders” are created.NASA/JPL-Caltech “The spiders are strange, beautiful geologic features in their own right,” said Lauren Mc Keown of NASA’s Jet Propulsion Laboratory in Southern California. “These experiments will help tune our models for how they form.”
The study confirms several formation processes described by what’s called the Kieffer model: Sunlight heats the soil when it shines through transparent slabs of carbon dioxide ice that built up on the Martian surface each winter. Being darker than the ice above it, the soil absorbs the heat and causes the ice closest to it to turn directly into carbon dioxide gas — without turning to liquid first — in a process called sublimation (the same process that sends clouds of “smoke” billowing up from dry ice). As the gas builds in pressure, the Martian ice cracks, allowing the gas to escape. As it seeps upward, the gas takes with it a stream of dark dust and sand from the soil that lands on the surface of the ice.
When winter turns to spring and the remaining ice sublimates, according to the theory, the spiderlike scars from those small eruptions are what’s left behind.
These formations similar to the Red Planet’s “spiders” appeared within Martian soil simulant during experiments in JPL’s DUSTIE chamber. Carbon dioxide ice frozen within the simulant was warmed by a heater below, turning it back into gas that eventually cracked through the frozen top layer and formed a plume.NASA/JPL-Caltech Re-Creating Mars in the Lab
For Mc Keown and her co-authors, the hardest part of conducting these experiments was re-creating conditions found on the Martian polar surface: extremely low air pressure and temperatures as low as minus 301 degrees Fahrenheit (minus 185 degrees Celsius). To do that, Mc Keown used a liquid-nitrogen-cooled test chamber at JPL, the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE.
“I love DUSTIE. It’s historic,” Mc Keown said, noting that the wine barrel-size chamber was used to test a prototype of a rasping tool designed for NASA’s Mars Phoenix lander. The tool was used to break water ice, which the spacecraft scooped up and analyzed near the planet’s north pole.
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This video shows Martian soil simulant erupting in a plume during a JPL lab experiment that was designed to replicate the process believed to form Martian features called “spiders.” When a researcher who had tried for years to re-create these conditions spotted this plume, she was ecstatic. NASA/JPL-Caltech For this experiment, the researchers chilled Martian soil simulant in a container submerged within a liquid nitrogen bath. They placed it in the DUSTIE chamber, where the air pressure was reduced to be similar to that of Mars’ southern hemisphere. Carbon dioxide gas then flowed into the chamber and condensed from gas to ice over the course of three to five hours. It took many tries before Mc Keown found just the right conditions for the ice to become thick and translucent enough for the experiments to work.
Once they got ice with the right properties, they placed a heater inside the chamber below the simulant to warm it up and crack the ice. Mc Keown was ecstatic when she finally saw a plume of carbon dioxide gas erupting from within the powdery simulant.
“It was late on a Friday evening and the lab manager burst in after hearing me shrieking,” said Mc Keown, who had been working to make a plume like this for five years. “She thought there had been an accident.”
The dark plumes opened holes in the simulant as they streamed out, spewing simulant for as long as 10 minutes before all the pressurized gas was expelled.
The experiments included a surprise that wasn’t reflected in the Kieffer model: Ice formed between the grains of the simulant, then cracked it open. This alternative process might explain why spiders have a more “cracked” appearance. Whether this happens or not seems dependent on the size of soil grains and how embedded water ice is underground.
“It’s one of those details that show that nature is a little messier than the textbook image,” said Serina Diniega of JPL, a co-author of the paper.
What’s Next for Plume Testing
Now that the conditions have been found for plumes to form, the next step is to try the same experiments with simulated sunlight from above, rather than using a heater below. That could help scientists narrow down the range of conditions under which the plumes and ejection of soil might occur.
There are still many questions about the spiders that can’t be answered in a lab. Why have they formed in some places on Mars but not others? Since they appear to result from seasonal changes that are still occurring, why don’t they seem to be growing in number or size over time? It’s possible that they’re left over from long ago, when the climate was different on Mars— and could therefore provide a unique window into the planet’s past.
For the time being, lab experiments will be as close to the spiders as scientists can get. Both the Curiosity and Perseverance rovers are exploring the Red Planet far from the southern hemisphere, which is where these formations appear (and where no spacecraft has ever landed). The Phoenix mission, which landed in the northern hemisphere, lasted only a few months before succumbing to the intense polar cold and limited sunlight.
News Media Contacts
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov
Karen Fox / Molly Wasser
Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
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Last Updated Sep 11, 2024 Related Terms
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By NASA
The dome-shaped Brandburg Massif, near the Atlantic coast of central Namibia, containing Brandberg Mountain, the African nation’s highest peak and ancient rock paintings going back at least 2,000 years, is pictured from the International Space Station as it orbited 261 miles above.
Image Credit: NASA
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By European Space Agency
Video: 00:01:00 Rover trials in a quarry in the UK showing a four-wheeled rover, known as Codi, using its robotic arm and a powerful computer vision system to pick up sample tubes.
The rover drives to the samples with an accuracy of 10cm, constantly mapping the terrain. Codi uses its arm and four cameras to locate the sample tube, retrieve it and safely store it on the rover – all of it without human intervention. At every stop, the rover uses stereo cameras to build up a 180-degree map of the surroundings and plan its next maneouvres. Once parked, the camera on top of the mast detects the tube and estimates its position with respect to the rover. The robotic arm initiates a complex choreography to move closer to the sample, fetch it and store it.
The sample tubes are a replica of the hermetically sealed samples inside which NASA’s Perseverance rover is collecting precious martian soil inside. To most people on Earth, they resemble lightsabres.
The reddish terrain, although not fully representative of Mars in terms of soil composition, has plenty of slopes and rocks of different sizes, similar to what a rover might encounter on the martian surface. Quarry testing is an essential next step in the development process, providing a unique and dynamic landscape that cannot be replicated indoors.
ESA continues to run further research using the rover to maintain and develop rover capabilities in Europe.
Read the full article: Rovers, lightsabres and a piglet.
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By NASA
Hubble Space Telescope Home NASA’s Hubble, MAVEN… Missions Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts E-books Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More Online Activities 6 min read
NASA’s Hubble, MAVEN Help Solve the Mystery of Mars’ Escaping Water
NASA, ESA, STScI, John T. Clarke (Boston University); Processing: Joseph DePasquale (STScI) Mars was once a very wet planet as is evident in its surface geological features. Scientists know that over the last 3 billion years, at least some water went deep underground, but what happened to the rest? Now, NASA’s Hubble Space Telescope and MAVEN (Mars Atmosphere and Volatile Evolution) missions are helping unlock that mystery.
“There are only two places water can go. It can freeze into the ground, or the water molecule can break into atoms, and the atoms can escape from the top of the atmosphere into space,” explained study leader John Clarke of the Center for Space Physics at Boston University in Massachusetts. “To understand how much water there was and what happened to it, we need to understand how the atoms escape into space.”
Clarke and his team combined data from Hubble and MAVEN to measure the number and current escape rate of the hydrogen atoms escaping into space. This information allowed them to extrapolate the escape rate backwards through time to understand the history of water on the Red Planet.
Escaping Hydrogen and “Heavy Hydrogen”
Water molecules in the Martian atmosphere are broken apart by sunlight into hydrogen and oxygen atoms. Specifically, the team measured hydrogen and deuterium, which is a hydrogen atom with a neutron in its nucleus. This neutron gives deuterium twice the mass of hydrogen. Because its mass is higher, deuterium escapes into space much more slowly than regular hydrogen.
Over time, as more hydrogen was lost than deuterium, the ratio of deuterium to hydrogen built up in the atmosphere. Measuring the ratio today gives scientists a clue to how much water was present during the warm, wet period on Mars. By studying how these atoms currently escape, they can understand the processes that determined the escape rates over the last four billion years and thereby extrapolate back in time.
Although most of the study’s data comes from the MAVEN spacecraft, MAVEN is not sensitive enough to see the deuterium emission at all times of the Martian year. Unlike the Earth, Mars swings far from the Sun in its elliptical orbit during the long Martian winter, and the deuterium emissions become faint. Clarke and his team needed the Hubble data to “fill in the blanks” and complete an annual cycle for three Martian years (each of which is 687 Earth days). Hubble also provided additional data going back to 1991 – prior to MAVEN’s arrival at Mars in 2014.
The combination of data between these missions provided the first holistic view of hydrogen atoms escaping Mars into space.
These are far-ultraviolet Hubble images of Mars near its farthest point from the Sun, called aphelion, on December 31, 2017 (top), and near its closest approach to the Sun, called perihelion, on December 19, 2016 (bottom). The atmosphere is clearly brighter and more extended when Mars is close to the Sun.
Reflected sunlight from Mars at these wavelengths shows scattering by atmospheric molecules and haze, while the polar ice caps and some surface features are also visible. Hubble and MAVEN showed that Martian atmospheric conditions change very quickly. When Mars is close to the Sun, water molecules rise very rapidly through the atmosphere, breaking apart and releasing atoms at high altitudes. NASA, ESA, STScI, John T. Clarke (Boston University); Processing: Joseph DePasquale (STScI)
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A Dynamic and Turbulent Martian Atmosphere
“In recent years scientists have found that Mars has an annual cycle that is much more dynamic than people expected 10 or 15 years ago,” explained Clarke. “The whole atmosphere is very turbulent, heating up and cooling down on short timescales, even down to hours. The atmosphere expands and contracts as the brightness of the Sun at Mars varies by 40 percent over the course of a Martian year.”
The team discovered that the escape rates of hydrogen and deuterium change rapidly when Mars is close to the Sun. In the classical picture that scientists previously had, these atoms were thought to slowly diffuse upward through the atmosphere to a height where they could escape.
But that picture no longer accurately reflects the whole story, because now scientists know that atmospheric conditions change very quickly. When Mars is close to the Sun, the water molecules, which are the source of the hydrogen and deuterium, rise through the atmosphere very rapidly releasing atoms at high altitudes.
The second finding is that the changes in hydrogen and deuterium are so rapid that the atomic escape needs added energy to explain them. At the temperature of the upper atmosphere only a small fraction of the atoms have enough speed to escape the gravity of Mars. Faster (super-thermal) atoms are produced when something gives the atom a kick of extra energy. These events include collisions from solar wind protons entering the atmosphere or sunlight that drives chemical reactions in the upper atmosphere.
Mars was once a very wet planet. Scientists know that over the last 3 billion years, some of the water went underground, but what happened to the rest? Credit: NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris; Mars Animations Producer: Dan Gallagher Serving as a Proxy
Studying the history of water on Mars is fundamental not only to understanding planets in our own solar system but also the evolution of Earth-size planets around other stars. Astronomers are finding more and more of these planets, but they’re difficult to study in detail. Mars, Earth and Venus all sit in or near our solar system’s habitable zone, the region around a star where liquid water could pool on a rocky planet; yet all three planets have dramatically different present-day conditions. Along with its sister planets, Mars can help scientists grasp the nature of far-flung worlds across our galaxy.
These results appear in the July 26 edition of Science Advances, published by the American Association for the Advancement of Science.
About the Missions
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
MAVEN’s principal investigator is based at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder. LASP is also responsible for managing science operations and public outreach and communications. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN mission. Lockheed Martin Space built the spacecraft and is responsible for MAVEN mission operations at Goddard. NASA’s Jet Propulsion Laboratory in Southern California provides navigation and Deep Space Network support. The MAVEN team is preparing to celebrate the spacecraft’s 10th year at Mars in September 2024.
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contacts:
Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, MD
claire.andreoli@nasa.gov
Ann Jenkins and Ray Villard
Space Telescope Science Institute, Baltimore, MD
Science Contact:
John T. Clarke
Boston University, Boston, MA
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Last Updated Sep 05, 2024 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
Astrophysics Astrophysics Division Goddard Space Flight Center Hubble Space Telescope Mars MAVEN (Mars Atmosphere and Volatile EvolutioN) Missions Planetary Science Planets Science Mission Directorate The Solar System Keep Exploring Discover More Topics From Hubble and Maven
Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
Hubble Science Highlights
MAVEN
The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission is the first mission devoted to understanding the Martian upper atmosphere.
Mars
Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited…
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