Space And The Universe News
The Discovery of a Hot Neptune that Shouldn’t Exist
by Evan Gough on March 23, 2023 at 5:53 pm
1800 light-years away, an unlikely survivor orbits an aged star. This rare planet is called a hot Neptune, and it’s one of only a small handful of hot Neptunes astronomers have found. Hot Neptunes are so close to their stars that the overpowering stellar radiation should’ve stripped away their atmospheres, leaving only a planetary core behind.
But this planet held onto its atmosphere somehow.
The more exoplanets we find, the better we understand the exoplanet population. With over 5,300 confirmed exoplanets, scientists are getting a handle on the makeup of the exoplanet population. On their Exoplanet Discovery Dashboard, NASA groups exoplanets into these categories: Neptune-like, Gas Giant, Super-Earth, and Terrestrial. Other classifications are used in space science, too, like hot Jupiter. But the hot Neptune tag isn’t used much because there aren’t many of them.
A hot Neptune is a gaseous planet that is extremely close to its star, just as a hot Jupiter is. When a gas planet gets too close to its star, the star can strip the gaseous atmosphere away. Hot Jupiters are so massive that they can hang on to their atmospheres with some success. But Neptune-size planets are much less massive than Jupiter-size planets, and really, hot Neptunes just shouldn’t exist. They’re not massive enough to hold onto their atmospheres in the face of all the stellar radiation. They defy the odds.
The first hot Neptune astronomers found is Gliese 436 b. Astronomers found it in 2004, five years before the Kepler mission changed exoplanet science forever. Researchers are still puzzling over Gliese 436 b and trying to understand how it held onto its atmosphere for this long. A 2015 paper concluded that the planet is losing mass and leaving a trail of hydrogen behind it as the star strips away its atmosphere.
In new research, astronomers from the USA and Australia presented their discovery of another hot Neptune. The paper is “An unlikely survivor: a low-density hot Neptune orbiting a red giant star.” The lead author is Samuel Grunblatt from the Department of Physics and Astronomy at Johns Hopkins University.
This hot Neptune is so close to its star that it completes an orbit in only 4.2 days. The planet, named TIC 365102760 b, is not very dense. Even though it’s about half the radius of Jupiter, its density is only 0.06 that of Jupiter’s. With a density that low, the planet shouldn’t be hanging onto its atmosphere.
The star is ancient, a red giant about 7.2 billion years old, and is 1.2 times as massive as the Sun. Its temperature is 4700 Kelvin (4400 C; 8,000 F.) Considering all these factors, TIC 365102760 b should be nothing but a planetary core by now. “The old age and high equilibrium temperature yet remarkably low density of this planet suggests that its gaseous envelope should have been stripped by high-energy stellar irradiation billions of years ago,” the authors write.
This planet is the rarest of the rare. There is only a small handful of Neptune-size planets orbiting a post-main sequence star, and it’s the only hot Neptune orbiting this type of star. Outliers like these are important because they can define Nature’s limits and help scientists build better models.
Current models can’t explain TIC 365102760 b and instead show that there should be nothing left by now but a core. “Thus, assuming that the planet did not experience migration or inflation after a system age of 20 Myr, most or all of the planet’s atmosphere should have been stripped over its lifetime,” the authors write.
How was it able to hold onto its mass for so long while being so close to its star?
The authors say that the explanation could lie in incorrect models of stellar flux. If the star isn’t as powerful as thought, then that could explain how the planet has held onto its atmosphere for so long. “First, the stellar flux in XUV may be significantly lower or absorbed less efficiently than existing models predict, preventing severe atmospheric erosion even if the planet has not changed its orbit or radius since formation.”
Migration could explain the planet, too, but only if it migrated during the star’s main sequence lifetime. “Second, the planet may have migrated to its current orbit during the main sequence lifetime of its host star from a previous larger orbit, avoiding the highest intensity of XUV irradiation from its host star,” they explain.
But there are some problems with that explanation. Star-planet and planet-planet interactions could’ve caused the migration, but there’s no indication of another large planet relatively near TIC 365102760 b. Interactions between a planet and a star can trigger migration, but in those cases, the planet has a highly-eccentric orbit. “Furthermore, TIC 365102760 b does not appear to have a high-eccentricity orbit, suggesting that migration due to star-planet interaction is also unlikely or not very recent in the system’s history,” the authors write.
The researchers suggest a third possibility to explain the hot Neptune. It could’ve been significantly smaller in the past, “… limiting the instantaneous rate of mass loss on the main sequence.” Planets are known to inflate as their stars leave the main sequence due to an increase in received radiation. But at this level of detail, much of the potential explanation comes down to different models, and there’s simply not enough clarity to attach any certainty to the explanation.
The researchers are shying away from the late-stage migration explanation. “Current observational evidence for both late-stage inflation and/or weak photoevaporation is stronger than evidence for late-stage migration in this system,” they explain. They think that a weaker level of XUV radiation from the star alongside late-stage inflation is the best explanation for this hot Neptune’s persistence.
But even without a clear explanation for TIC 365102760 b’s resilience, the planet and this research are telling planetary scientists some important things.
“The discovery of a low-density hot Neptune orbiting an evolved star demonstrates that the atmospheres of these planets are more resilient than previously thought,” the authors write. The planet’s existence also shows that planets smaller than Jupiter can become inflated as their stars evolve out of the main sequence. This has implications for our understanding of how Neptune-size planets form and evolve and implications for how scientists interpret the exoplanet population.
Since the star and planet are so closely intertwined, these results can tell us something about planet composition and stellar activity, too. But that still needs to be untangled. Finding more of these rare planets is the obvious path forward, but they don’t often appear in general searches. “Focused searches for these evolved systems are necessary as these planets are missed by general searches for transiting planets,” the authors write.
As for TIC 365102760 b’s specific case, follow-up observations could more tightly constrain the planet’s characteristics and help explain its existence. Ground-based and space-based spectroscopic studies could reveal atmospheric outflows from the planet more clearly and could shed light on the lifetime of its atmosphere as well as the atmosphere’s composition.
“Constraining the balance between planet atmospheric inflation and mass loss will help reveal the evolution of planetary atmospheres over time, clarifying planet demographic features such as the hot Neptune desert,” the authors conclude.
- New Research: An unlikely survivor: a low-density hot Neptune orbiting a red giant star
- Older Research: A giant comet-like cloud of hydrogen escaping the warm Neptune-mass exoplanet GJ 436b
- Universe Today: A Very Rare Planet Discovered. Less Massive than Neptune, Hotter than Mercury. Very Few Should Exist
The post The Discovery of a Hot Neptune that Shouldn’t Exist appeared first on Universe Today.
Fly Around Jezero Crater on Mars in This New Video
by Nancy Atkinson on March 23, 2023 at 12:46 pm
There’s a reason Jezero Crater was chosen as the landing site for the Perseverance Rover: it is considered one of the likeliest places to find any evidence if Mars was ever habitable for long periods of time. In this great new flyby video from ESA, you can get a birds-eye look at Perseverance’s home.
Created from data ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter, the video takes you on an aerial tour of the crater. From this perspective, you can see the water features in this ancient impact crater and understand why this was considered one of the best places to explore Mars.
Perseverance landed in Jezero crater in February 2021. The diverse rocks and mineralogy found in and around Jezero crater tell the story of Mars’ complex geological history, which Perseverance is working to study and reveal. The roughly 45-km-wide crater is found on the border between the ancient region of Terra Sabaea – which contains rocks of up to 4.1 billion years old – and the younger Isidis Planitia basin, which formed via asteroid impact.
Did the crater ever host water? The evidence so far suggests the wall of Jezero is breached by three valleys that were once rivers of flowing water, and the crater is considered to be an ancient ‘open basin lake’ in that water once flowed both into and out of the crater, a type of basin that is especially promising in the hunt for life on Mars.
In the video, you’ll see an outflow channel snaking away from the crater wall and towards the camera perspective. Then you’ll see two inflow channels (Neretva Vallis and Sava Vallis, found on the western-northwestern rim of Jezero. the most prominent of these branches out into the crater to form an ancient fan-shaped river delta that was the landing site for Perseverance.
Or are these features created by ancient volcanism? Jezero sits next to an intriguing system of faults known as Nili Fossae and a prominent area of volcanism named Syrtis Major, where lava flowed some three billion years ago.
To really know for sure, scientists will need to study Mars close up. To that end, Perseverance is collecting samples of Martian rock and soil and putting them in special containers that will one day be picked up by a future sample return mission. NASA and ESA are working together on this mission, which ESA says will be more advanced than any robotic missions that have gone before, but it will revolutionize our understanding of both the Red Planet and the Solar System.
The post Fly Around Jezero Crater on Mars in This New Video appeared first on Universe Today.
Did Supernovae Help Push Life to Become More Diverse?
by Carolyn Collins Petersen on March 22, 2023 at 6:50 pm
Life on Earth has been around for a long time—at least 3.8 billion years. During that time, it evolved significantly. Why has biodiversity here changed so much? A new study proposes a startling idea. Some major diversity changes are linked to supernovae—the explosions of massive stars. If true, it shows that cosmic processes and astrophysical events can influence the evolution of life on our planet.
The idea of cosmic catastrophes having an effect on life is not new. Usually, people think about such events happening to us in modern times. But, there’s a long history of Earth being affected by past cosmic events. It’s likely, for example, that shock waves from supernova explosions set the birth process of our Sun in motion. We experience solar flares and outbursts and how they interfere with our technology. We also know that impacts have shaped the planet throughout its history, as well. So, why couldn’t supernovae also play a role in the evolution of life? There are a lot of ideas about that, involving both astronomical and biological research.
Linking Supernovae to Life Changes
A team of scientists at DTU Space (Denmark’s largest space research institute) think there’s a strong correlation between changes in the diversity of marine life in the past half a billion years and the occurrence of nearby supernova explosions. According to Henrik Svensmark, author of a paper describing the team’s research, it’s possible that one effect of a supernova is a change in Earth’s climate. “A high number of supernovae leads to a cold climate with a large temperature difference between the equator and polar regions,” he said. “This results in stronger winds, ocean mixing, and transportation of life-essential nutrients to the surface waters along the continental shelves.”
The team’s paper points out some interesting specifics. It states, “In accordance with the cosmic ray theory, Earth experienced cold glacial periods when the local supernova frequency was high, i.e., high cosmic rays and warm climates when the flux was low. These results suggest that changes in supernovae frequency and, thereby, changes in cosmic rays have significantly influenced the Phanerozoic climate.”
This proposed influence of supernova explosions extends to the conditions for life. For example, the paper suggests a correlation between past supernova rates and the burial of organic matter in ocean sediments during the last 500 million years. The sequence goes like this: supernovae rates influence climate. Climate influences atmosphere–ocean circulation. That circulation brings nutrients to marine organisms. Nutrient concentrations control bioproductivity (how organisms thrive). Then, as they die, their remains settle into sea sediments, which fossilize and preserve the record of past biological activity.
All of this appears to correlate with changes in supernova rates. If this link turns out to be solid, then supernovae may well influence climate and the energy available to biological systems. And all that has an influence on marine life.
Searching the Fossil Record for Supernova Evidence
So, what evidence is Svensmark’s team offering? They studied the fossil record of ancient shallow marine areas. These were along the edges of oceans and other bodies of water in the Phanerozoic period of Earth’s geologic history. That’s the period of time we’re in now. It began some 542 million years ago. These shallow marine shelves are relevant since most marine life thrives in these areas. By studying the rates of change in species of life they found clear evidence of explosions in biodiversity.
The team then looked at the astrophysical fossil record of supernovae. They studied supernova frequencies recorded in three data sets of open stellar clusters in the solar neighborhood. Those catalogs contain data about clusters within 850 parsecs of the Sun, with ages 520 million years and younger. The team then correlated the data from the two sets with each other to link higher-than-normal rates of past supernova explosions with climate-influenced changes in biodiversity in shallow marine environments.
How Can Supernovae Do This?
How does this proposed link between climate change and supernovae work? Let’s look at the chain of events that leads from star death to biodiversity changes on Earth. You start with a star at least 8 times the mass of the Sun. When this massive progenitor star reaches the end of its life, it collapses in on itself. The infalling material rebounds off the stellar core and rushes out to space. That cloud of debris scatters all the elements made by the star both before and during the supernova explosion. The event also emits huge amounts of cosmic rays. Those energetic particles eventually arrive in our Solar System. Some smash into Earth’s atmosphere and send showers of ions crashing through the atmosphere. There, they help create the aerosols that form clouds.
Clouds help regulate solar energy by controlling how much sunlight reaches Earth’s surface. The warmth of the sunlight is one part of the water-warmth-nutrient triad that enables life to form and thrive on the planet. So, in a very real sense, the influence of supernovae is part of the cycle of substantial climate shifts, thanks to the intensity of cosmic rays. According to Svensmark, those changes can be as much as several hundred percent over millions of years. “The new evidence points to a connection between life on Earth and supernovae, mediated by the effect of cosmic rays on clouds and climate”, he said.
If this idea Svensmark’s team is proposing stands, then it’s yet another link between distant astrophysical activities and the evolution of life on our planet.
For More Information
Supernovae and life on Earth appears to be closely connected
A Persistent Influence of Supernovae on Biodiversity Over the Phanerozoic
The post Did Supernovae Help Push Life to Become More Diverse? appeared first on Universe Today.
Another Look at the Aftermath of DART's Impact Into Dimorphos
by Nancy Atkinson on March 22, 2023 at 2:35 pm
When the DART spacecraft slammed into asteroid Dimorphos on September 26, 2022, telescopes worldwide (and in space) were watching as it happened. But others continued watching for numerous days afterward to observe the cloud of debris. DART’s (Double Asteroid Redirection Test) intentional impact was not only a test of planetary defense against an asteroid hitting our planet, but it also allowed astronomers the chance to study Dimorphos, a tiny moon or companion to asteroid Didymos.
New images released by the European Southern Observatory’s Very Large Telescope (VLT) show how the surface of the asteroid changed immediately after the impact when pristine materials from the interior of the asteroid were exposed. Other data tracked the debris’ evolution over a month, and provided details on how the debris changed over time. Additionally, astronomers searched for evidence of DART’s fuel but couldn’t find any.
“Impacts between asteroids happen naturally, but you never know it in advance,” said Cyrielle Opitom, an astronomer at the University of Edinburgh and lead author of one of two studies just published about the impact. “DART is a really great opportunity to study a controlled impact, almost as in a laboratory.”
All four of the 8.2-meter telescopes of the VLT in Chile observed the aftermath of the impact, which occurred when Dimorphos was 11 million kilometers away from Earth.
The first study, led by Stefano Bagnulo, an astronomer at the Armagh Observatory and Planetarium in the Northern Ireland, studied how the DART impact altered the surface of the asteroid.
“When we observe the objects in our Solar System, we are looking at the sunlight that is scattered by their surface or by their atmosphere, which becomes partially polarized,” said Bagnulo, in an ESO press release. This means that light waves oscillate along a preferred direction rather than randomly. “Tracking how the polarization changes with the orientation of the asteroid relative to us and the Sun reveals the structure and composition of its surface.”
Bagnulo and his team used the FOcal Reducer/low dispersion Spectrograph 2 (FORS2) instrument at the VLT to monitor the asteroid, and found that the level of polarization suddenly dropped after the impact. At the same time, the overall brightness of the system increased. One possible explanation is that the impact exposed more pristine material from the interior of the asteroid.
“Maybe the material excavated by the impact was intrinsically brighter and less polarizing than the material on the surface, because it was never exposed to solar wind and solar radiation,” said Bagnulo.
However, another possibility is that the impact destroyed particles on the surface, thus ejecting much smaller ones into the cloud of debris. “We know that under certain circumstances, smaller fragments are more efficient at reflecting light and less efficient at polarizing it,” said Zuri Gray, a PhD student also at Armagh.
In the second study Opitom and her team tracked the evolution of the debris cloud from the collision for a month with the Multi Unit Spectroscopic Explorer (MUSE) instrument on the VLT. MUSE allowed the astronomers to study the spectrum of chemicals and gases present in the debris. In particular, they searched for oxygen and water coming from ice exposed by the impact, but they found nothing.
“Asteroids are not expected to contain significant amounts of ice, so detecting any trace of water would have been a real surprise,” said Opitom in and ESO press release. They also looked for traces of the propellant of the DART spacecraft, but found none. “We knew it was a long shot,” she said, “as the amount of gas that would be left in the tanks from the propulsion system would not be huge. Furthermore, some of it would have travelled too far to detect it with MUSE by the time we started observing.”
As the debris expanded outward, astronomers noticed that structures started forming, such as clumps, spirals and a long tail pushed away by the Sun’s radiation. Parts of the debris started redder and shifted into blue, indicating that the solar wind pushed smaller particles away from the Sun. Other parts of the debris were redder than the initial cloud, meaning that the clumps and structures were made of larger particles that were less affected by the solar wind.
ESO said the two studies show the potential of the VLT when its different instruments work together. In fact, in addition to MUSE and FORS2, the aftermath of the impact was observed with two other VLT instruments, and analysis of these data is ongoing.
“This research took advantage of a unique opportunity when NASA impacted an asteroid,” said Opitom, “so it cannot be repeated by any future facility. This makes the data obtained with the VLT around the time of impact extremely precious when it comes to better understanding the nature of asteroids.”
Read the teams’ papers:
“Optical spectropolarimetry of binary asteroid Didymos-Dimorphos before and after the DART impact” published in Astrophysical Journal Letters (doi:10.3847/2041-8213/acb261).
“Morphology and spectral properties of the DART impact ejecta with VLT/MUSE” published in Astronomy & Astrophysics (doi:10.1051/0004-6361/202345960).
The post Another Look at the Aftermath of DART's Impact Into Dimorphos appeared first on Universe Today.
A New Mission Will Search for Habitable Planets at Alpha Centauri
by Matt Williams on March 21, 2023 at 9:45 pm
Alpha Centauri is our closest stellar neighbor, a binary star system located just 4.376 light-years away. Despite its proximity, repeated astronomical surveys have failed to find hard evidence of extrasolar planets in this system. Part of the problem is that the system consists of two stars orbiting each other, which makes detecting exoplanets through the two most popular methods very challenging. In 2019, Breakthrough Initiatives announced they were backing a new project to find exoplanets next door – the Telescope for Orbit Locus Interferometric Monitoring of our Astronomical Neighbourhood (TOLIMAN, after the star’s ancient name in Arabic).
This low-cost mission concept was designed by a team from the University of Sydney, Australia, and aims to look for potentially-habitable exoplanets in the Alpha Centauri system using the Astrometry Method. This consists of monitoring a star’s apparent position in the sky for signs of wobble, indicating that gravitational forces (like planets) are acting on it. Recently, the University of Sydney signed a contract with EnduroSat, a leading microsatellites and space services provider, to provide the delivery system and custom-built minisatellite that will support the mission when it launches.
Alpha Centauri consists of a G-type primary star (similar to our Sun) and a K-type (orange dwarf) secondary. Because of its binary nature, it has been very difficult to discern possible signals from this system that could be the result of exoplanets. This includes the Transit Method, where astronomers monitor stars for periodic dips in luminosity that may indicate planets passing in front of the star (transiting) relative to the observer. But since the stars also make transits, dips in luminosity are very common.
Similarly, the way the stars co-orbit each other significantly affects their movement back and forth (aka. radial velocity). This makes it very difficult to detect planets that could be orbiting them, as indicated by how their gravitational influence affects the star’s movement (the Radial Velocity Method). However, this same method confirmed the existence of a rocky planet (Proxima b) orbiting within Proxima Centauri’s habitable zone in 2016. Two more have been found since, including an innermost Mars-sized rocky planet and an outermost gas giant (possibly with rings!)
So far, astronomers have reported numerous possible signals from Alpha Centauri. The first occurred in 2012 when astronomers reported an RV signal from Alpha Centauri B that was attributed to a planet (Alpha Centauri Bb) but which was revealed to be a false positive in 2015. A possible planetary transit was announced in 2013, but it was reportedly too close to its primary to support life. In 2021, a candidate planet named Candidate 1 (C1) was detected around Alpha Centauri A using direct thermal imaging, but this remains unconfirmed.
To Peter Tuthill, a professor of physics with the Sydney Institute for Astronomy (SIfA) and the lead scientist on the TOLIMAN mission, the difficult task of confirming planets around Alpha Centauri A and B is too tempting to pass up. As he said in a recent University of Sidney press release:
“That’s tantalizingly close to home. Astronomers have discovered thousands of exoplanets outside our own Solar System, but most are thousands of light years away and beyond our reach. Modern satellite technology will allow us to explore our celestial backyard and perhaps lay the groundwork for visionary future missions spanning the interstellar voids to the Centauri system.”
As we explored in a previous article, the TOLIMAN concept was first proposed by Tuthill and his SIfA colleagues during the 2018 SPIE Astronomical Telescopes+Instrumentation Conference in Austin, Texas. Rather than concentrating light into a focused beam like conventional telescopes, the TOLIMAN relies on a diffractive pupil mirror pattern that spreads starlight into a complex flower pattern, allowing for extremely fine measurements of a star’s motion. Any indications of exoplanets can then be followed by more powerful instruments not dedicated exclusively to monitoring Alpha Centauri.
“Any exoplanets we find that close to Earth can be followed up with other instruments, giving excellent prospects for discovering and analyzing atmospheres, surface chemistry, or even fingerprints of a biosphere – the tentative signs of life,” said Tuthill. These follow-up studies are something telescopes like the James Webb and the next-generation instruments like the Nancy Grace Roman Space Telescope (RST), scheduled to launch in 2027. Alpha Centauri is also likely to be a popular target for the many 30-meter ground-based telescopes that will become operational in this decade.
Launching this telescope will be a tall order, requiring a limited volume (12 liters) that can maintain thermal and mechanical stability. To this end, the Universtiy of Sydney has contracted with EnduroSat to provide a custom-built mini satellite as the delivery system. Their MicroSat design can downlink payload data at a speed of more than 125 megabits per second (Mbps), which is crucial for an ongoing observation mission where lots of data downloads will come into play. As Raycho Raychev, the Founder and CEO of EnduroSat, remarked:
“We are exceptionally proud to partner in this mission. The challenges are enormous, and it will drive our engineering efforts to the extreme. The mission is a first-of-its-kind exploration science effort and will help open the doors for low-cost astronomy missions.”
This latest project is one of several backed by Breakthrough Initiatives, which is already having an impact with its advanced project Breakthrough Listen – the largest program ever mounted dedicated to the search for extraterrestrial intelligence (SETI). The TOLIMAN project also fits nicely with Breakthrough Starshot, a proposed interstellar mission that will leverage advances in miniaturization, advanced materials, and directed-energy propulsion to send a nanocraft to Alpha Centauri within a single lifetime (20 years).
Detecting planets next door will likely go a long way toward inspiring interstellar missions to explore the system up close. Said Dr. S. Pete Worden, the former director of NASA’s Ames Research Center (2006 to 2015) and the Executive Director of Breakthrough Initiatives: “It’s very exciting to see this program come to life. With these partnerships, we can create a new kind of astronomical mission and make real progress on understanding the planetary systems right next door.”
Further Reading: University of Sydney
The post A New Mission Will Search for Habitable Planets at Alpha Centauri appeared first on Universe Today.
Machine Learning Finds 140,000 Future Star Forming Regions in the Milky Way
by Andy Tomaswick on March 21, 2023 at 2:50 pm
Our galaxy is still actively making stars. We’ve known that for a while, but sometimes it’s hard to understand the true scale in astronomical terms. A team from Japan is trying to help with that by using a novel machine-learning technique to identify soon-to-be star-forming regions spread throughout the Milky Way. They found 140,000 of them.
The regions, known in astronomy as molecular clouds, are typically invisible to humans. However, they do emit radio waves, which can be picked up by the massive radio telescopes dotted around our planet. Unfortunately, the Milky Way is the only galaxy close enough where we can pick up those signals, and even in our home galaxy; the clouds are so far spread apart it has been challenging to capture an overall picture of them.
Therefore a team from Osaka Metropolitan University thought – machine learning to the rescue. They took a data set from the Nobeyama radio telescope located in Nagano prefecture and looked for the prevalence of carbon monoxide molecules. That resulted in an astonishing 140,000 visible molecular clouds in just one quadrant of the Milky Way.
As a next step, the team looked deeper into the data and figured out how large they were, as well as where they were located in the galactic plane. Given that there are four more quadrants to explore, there’s a good chance there are significantly more to find.
But to access at least two of those quadrants, they need a different radio telescope. Nobeyama is located in Japan, in the northern hemisphere, and can’t see the southern sky. Plenty of radio telescopes, such as ALMA, are already online in the southern hemisphere. Some are on the horizon, such as the Square Kilometer Array that could provide an even farther look around the southern hemisphere’s galactic plane. The team just needs to pick which one they would like to use.
One of the great things about AI is that once you train it, which can take a significant amount of time, analyzing similar data sets is a breeze. Future work on more radio data should take advantage of that fact and allow Dr. Shinji Fujita and his team to quickly analyze even more star-forming regions. With some additional research, we’ll be able to truly understand our galaxy’s creation engine sometime in the not-too-distant future.
Osaka Metropolitan University – AI draws most accurate map of star birthplaces in the Galaxy
Fujita et al. – Distance determination of molecular clouds in the first quadrant of the Galactic plane using deep learning: I. Method and results
UT – One of the Brightest Star-Forming Regions in the Milky Way, Seen in Infrared
UT – Speedrunning Star Formation in the Cygnus X Region
Image of star-forming region Sharpless 2-106, about 2,000 light years away from Earth.
Credit – NASA , ESA, STScI/Aura
The post Machine Learning Finds 140,000 Future Star Forming Regions in the Milky Way appeared first on Universe Today.
If Titan Has the Chemistry For Life, Dragonfly Could Find it
by Nancy Atkinson on March 21, 2023 at 2:09 pm
The highly-anticipated Dragonfly robotic rotocraft mission to Saturn’s moon Titan is scheduled to launch in 2027. When it arrives in the mid-2030s, it will hover and zoom around in the thick atmosphere of Titan, sampling the air and imaging the landscape. What could be more exciting than that!?
Well, actually … there’s more: Dragonfly will also be equipped with a mass spectrometer that will help it search for the chemistry of life in this alien world. Astrobiologists want to know if Titan has the same type of chemistry on its surface that Earth did in its early history, which could have helped give rise to life on our planet.
Titan, the second largest moon in our Solar System, is the only known moon with an atmosphere. It is the most Earth-like place we know of, as it has rain, lakes, and oceans. But at Titan’s frigid surface temperatures — roughly -180 degrees Celsius (-292 degrees Fahrenheit) — liquid methane and ethane dominate Titan’s hydrocarbon equivalent of Earth’s water. But this complex carbon-rich chemistry, as well as Titan’s interior ocean make it an ideal destination to study the prebiotic chemical processes that could lead to the formation of life.
Dragonfly’s Mass Spectrometer (DraMS) is designed to help scientists remotely study the chemistry at work on Titan, measuring samples of Titan’s surface materials to look for evidence of what is called prebiotic chemistry, the chemical steps that lead to the formation of life.
“We want to know if the type of chemistry that could be important for early pre-biochemical systems on Earth is taking place on Titan,” said Dr. Melissa Trainer of NASA’s Goddard Space Flight Center, Greenbelt, Maryland, in a NASA press release.
Trainer, a planetary scientist and astrobiologist who specializes in Titan, is one of the Dragonfly mission’s deputy principal investigators. She is also lead on the DraMS instrument.
A mass spectrometer can analyze the various chemical components of a sample by separating these components down into their base molecules and passing them through sensors for identification.
Dragonfly will capitalize Titan’s low gravity (13.8% that of Earth), enabling the rotocraft to remain airborne and perform like a drone, researching a variety of things on Titan, including the atmosphere, the surface, and the methane lakes and rivers.
NASA says that Dragonfly has the ability to fly between different points of interest on Titan’s surface, spread as far as several kilometers/miles apart. This will allow Dragonfly to relocate its entire suite of instruments to a new site when the previous one has been fully explored, and provides access to samples in environments with a variety of geologic histories to learn more about the moon’s composition and its potential to support life.
“DraMS is designed to look at the organic molecules that may be present on Titan, at their composition and distribution in different surface environments,” said Trainer. Organic molecules contain carbon and are used by all known forms of life. They are of interest in understanding the formation of life because they can be created by living and non-living processes.
At each site, samples less than a gram in size will be drilled out of the surface by the Drill for Acquisition of Complex Organics (DrACO) and brought inside the lander’s main body, to a place called the “attic” that houses the DraMS instrument. There, the samples will be irradiated by an onboard laser or vaporized in an oven to be measured by DraMS.
DraMS utilizes proven mass spectrometer technologies that have used on the Mars rovers.
“This design has given us an instrument that’s very flexible, that can adapt to the different types of surface samples,” said Trainer.
Dragonfly will land in an equatorial, dry region of Titan called the Shangri-La dune field, close to an 80 km wide (50-mile-wide) crater called Selk. This region was imaged by NASA’s Cassini spacecraft during its mission to Saturn between 2004 and 2017 has a terrain of dunes and shattered, icy bedrock, according radar imagery from Cassini.
The post If Titan Has the Chemistry For Life, Dragonfly Could Find it appeared first on Universe Today.
JWST Sees Organic Molecules Swirling Around a Newborn Star
by Carolyn Collins Petersen on March 21, 2023 at 4:06 am
One of the most interesting questions we can ask is, “How did life form?”. To answer it, scientists go back to look at the basic chemical building blocks of life. Those are water, carbon-based organic molecules, silicates, and others. The James Webb Space Telescope offered a peek at the gases, ice particles, and dust surrounding a newborn star and found organic molecules exist there.
The data from Webb is set to transform our understanding of the chemistry of newly formed stars. That’s because the telescope can detect the existence of organic molecules around the protostar MIRI 15398-3359. It’s forming in the Lupus 1 molecular cloud (also known as B228), some 500 light-years away from us. The telescope has found absorption features indicating the existence of water, methanol, ammonia, and methane ices. There also appear to be species of ethanol and acetaldehyde, in addition to carbon monoxide and water vapor. These are all complex organic molecules that can combine to form the building blocks of life.
Using Other Molecules to Track Stellar Activity
Since this is a newborn protostar, it’s showing some jet activity as well. Webb found emission lines from species of iron, neon, silicon, and hydrogen gas. These all trace a bipolar jet moving away from the stormy young star. MIRI 15398-3359, like many others, is still feeding on the envelope of material that created it. The cloud of gas and dust that formed its creche is chemically active.
Essentially, it’s taking simple building blocks and churning out those complex organic molecules. They’re precursors to the chemicals of life—existing long before conditions on any nearby worlds have even formed. This is not the first time astronomers have the raw materials for life’s chemicals in stellar nurseries. Other clouds of gas and dust seem to show these complex chemicals, too. But, Webb’s exquisite data show more details about what’s going on in the cloud.
Forming Organic Molecules
A research team at the Japanese research institution RIKEN analyzed the Webb data from this newly forming star. They concluded that these complex organic molecules are forming on the surfaces of ice grains in the cloud of gas and dust. As the star warms those molecules, they migrate away from their icy homes and swirl into the cloud.
“We want to obtain definitive proof of such formation pathways,” said Yao-Lun Yang of the RIKEN Star and Planet Formation Laboratory. “And JWST provides the best opportunity to do so.”
To understand what’s happening at the star, Yang and the team used data from observations of the star made by Webb’s Mid-Infrared Instrument (MIRI) in 2022. It wasn’t the first time telescopes had looked at MIRI 15398-3359. Previous observations had found some of these chemicals in the gas phase—well after they’d formed. The MIRI observations dug more deeply into the cloud to identify these species in their ice phase.
An Early Peek at a Baby Star
The process of star birth has long been veiled by the clouds where those chemicals exist. Specialized instruments such as MIRI look more deeply into the clouds. It offers a view of chemical evolution much earlier in the process of star formation. The observations also allowed astronomers to put a tentative time frame on the existence of the jets and outflows from this baby star. According to Yang, the ejections are perhaps only 170 years old. That’s incredibly early in the process. But, it does give astronomers a good idea of just how soon a newborn star becomes active. The observation of complex organic chemicals in the cloud in both gas and ice form also tells scientists more about the chemical evolution that takes place in stellar creches.
As the star progresses in its evolution, and possible planets form in the protoplanetary disk around MIRI 15398-3359, Webb should be able to continue peeking inside its birthplace. Tracing the formation of life on those planets will require scientists to track the continued evolution of those complex organic molecules from gas clouds to a planetary surface. It’s a very promising breakthrough in understanding the long road from star formation to life. “We will begin to understand how organic chemistry emerges,” said Yang. “And we will also uncover the lasting impacts on planetary systems similar to our Solar System.”
For More Information
Space Telescope Probes Chemistry Around a Newborn Star
CORINOS. I. JWST/MIRI Spectroscopy and Imaging of a Class 0 Protostar IRAS 15398–3359
The post JWST Sees Organic Molecules Swirling Around a Newborn Star appeared first on Universe Today.
The Favorite Solar System Moons of Planetary Geologists; An In-Depth Discussion
by Laurence Tognetti on March 21, 2023 at 2:41 am
The moons of our Solar System have garnered quite a lot of attention in the last few years, especially pertaining to astrobiology and the search for life beyond Earth. From the Galilean moons of Jupiter to the geysers of Enceladus to the methane lakes on Titan, these small worlds continue to humble us with both their awe and mystery. But do the very same scientists who study these mysterious and intriguing worlds have their own favorite moons? As it turns out, seven such planetary geologists were kind enough to share their favorite Solar System moons with Universe Today!
“My favorite moon is Enceladus, for two reasons,” said Dr. Francis Nimmo, who is a professor in the Earth & Planetary Sciences Department at UC Santa Cruz. “First, it is geologically active, which was very surprising given how tiny it is – it is spewing jets of ice and water vapor into space. Second, because it is kind enough to be giving us free samples of its interior, it makes a very attractive target for future spacecraft missions – you can analyze the composition of the ocean (and even look for life) without having to drill through the ice.”
Saturn’s sixth-largest moon, Enceladus, was discovered in 1789 by William Herschel, and whose diameter is approximately the size of the State of Arizona. As noted by Dr. Nimmo, Enceladus possesses geysers that discharge ice and water vapor from a series of fissures known as “tiger stripes”. These geysers were first observed by NASA’s Cassini spacecraft during its mission in the 2000s, and Cassini even flew through them to test their composition, finding water vapor, a variety of salts, methane, and carbon dioxide.
“My favorite moon of the Solar System is Io, the innermost of the Galilean satellites of Jupiter,” said Dr. David Williams, who is a research professor in the School of Earth and Space Exploration at Arizona State University. “Discovered by Galileo Galilei in January of 1610, Io is the most geologically active of all of the moons of our Solar System. A Laplace orbital resonance with Jupiter’s other moons Europa and Ganymede results in tidal flexing and heating of Io’s interior, producing an enormous amount of energy that powers over 400 volcanoes on Io’s surface. Io’s volcanic activity, which manifests as both lava flows and lava lakes in caldera-like craters, and in explosive eruption plumes that shoot silicate ash, dust, and sulfur-bearing gases hundreds of kilometers above the surface, results in a world without any large impact craters. This indicates that Io has the geologically youngest surface in the Solar System. Thus, Io serves as an example of potentially active, volcanic lava planets discovered around other stars in our Galaxy.”
Jupiter’s first Galilean moon, Io, was first visited by NASA’s Pioneer 10 and 11 in December 1973 and December 1974, respectively, but only one image was taken by Pioneer 11 during the brief flyby. It wasn’t until Voyager 1 and 2 flew through the Jupiter system in 1979 that scientists got their first real look at this mysterious moon, revealing a crater-less surface and was the first planetary object other than Earth to be observed exhibiting volcanic activity, which is due to the tidal heating between Io and the much more massive Jupiter, along with Europa orbiting just beyond Io.
“The truth is, when it comes to moons, I could never pick one,” said Dr. Alyssa Rhoden, who is a principal scientist at the Southwest Research Institute. “They are all intriguing in their own ways, and each one teaches us something different. Although I don’t have a favorite, I will take the opportunity to highlight one particular moon that doesn’t get much attention: Proteus, a small moon of Neptune. Compared to Neptune’s large active moon, Triton, it seems reasonable to neglect battered little Proteus. But here’s the thing…Proteus is in the same size range as Mimas and Enceladus (around Saturn), and Miranda (around Uranus), which are much more round and brighter than Proteus,” Dr. Rhoden continues. “Enceladus is geologically active with very high heat flows and plumes at its South Pole, showing that even small moons can be quite interesting. And yet, Proteus is heavily cratered, with so many large craters that it doesn’t even look spherical anymore.”
Proteus is Neptune’s second-largest moon, and was discovered by Voyager 2 in 1989 when the spacecraft flew through the Neptune system. Despite its non-spherical shape, Proteus shows no signs of current geologic activity, unlike Neptune’s much larger moon, Triton, and is one of the darkest objects in the Solar System.
“Of course, my favorite moon is Triton!!” Dr. Candice Hansen-Koharchek, who is a planetary scientist and was a Voyager Imaging Team Assistant Experiment Representative during the Voyager missions, exclaimed. “There is so much that we still don’t know…very fundamental questions like whether or not it has an internal ocean, whether or not the bizarre features on the surface are cryovolcanic and whether or not the surface and the sub-surface ocean interact. What is the composition of the bright south polar region? How are different ices distributed across the surface? Sooooo many interesting questions…”
Triton was discovered by William Lassell in 1846. It is the largest of Neptune’s 13 moons, and possibly the most intriguing, with its cantaloupe terrain and dark streaks from geysers across its surface, which Voyager scientists determined to be geysers when Voyager 2 flew past in 1989, Triton could possibly contain an interior liquid ocean. Despite the very brief flyby, scientists learned a great deal about this small moon, whose diameter is approximately one-half the width of the United States at 2,700 kilometers (1,680 miles). No spacecraft are currently exploring Triton or are scheduled to travel out there, so Voyager 2 remains the only human-made object to visit this mysterious and intriguing moon way out in the depths of the Solar System.
“Europa, the sixth-largest moon in the solar system, is without a doubt my favorite moon,” said Dr. Antonio Paris, who is the Chief Research Scientist with The Center for Planetary Science. “Recent research of Europa has uncovered inferred evidence of an ocean of water below the moon’s icy surface. Europa, therefore, may have the necessary ingredients for life: water, energy, and complex molecules known as organics. The current data, however, is still speculation at best. Therefore, planetary scientists like myself hope to find the answers with the Europa Clipper mission!”
Like Io, Jupiter’s second Galilean moon, Europa, was discovered by Galileo Galilei in 1610, and also exhibits a crater-less surface due to tidal heating, as well. But instead of extreme volcanism, Europa harbors an interior ocean that is estimated to contain more than twice the volume of all of Earth’s oceans combined despite Europa being smaller than Earth’s Moon. Europa was first explored up close by Voyager 1 and 2 in 1979, which presented strong evidence of an interior ocean beneath the Europa’s ice shell. Dr. Paris mentions NASA’s Europa Clipper mission, which is a NASA Flagship mission designed to explore Europa for potential signs of habitability within the small moon’s deep ocean.
“My favorite moon in the Solar System is Saturn’s giant moon, Titan,” said Dr. Jason Barnes, who is a professor in the Department of Physics at the University of Idaho. “Titan is particularly awesome because it is a member of so many different planetary clubs. Titan’s subsurface liquid water mantle makes it an Ocean World, like Europa, Ganymede, and Enceladus. But at the same time Titan is one of just four places that we know of in the entire universe that sport both a solid surface and a thick atmosphere, along with Venus, Earth, and Mars. Only Earth and Titan have lakes and seas of surface liquid, and it’s just Earth and Titan again that have extensive water in the vicinity of complex organic molecules. All of these make Titan a logical choice for future exploration, and that’s why we’re sending the Dragonfly relocatable lander to Titan to investigate possibly prebiotic chemistry, to ascertain its habitability, and to search for chemical signatures of potential life there. Dragonfly launches in 2027 June and will arrive at Titan after a 6.5-year space cruise, after which it will fly in Titan’s air to more than 20 different landing sites as a nearly one-ton octocopter. We look forward to sharing Dragonfly’s adventure with you all once it arrives by 2034!”
Saturn’s largest moon, Titan, which is also the second largest moon in the Solar System, was discovered by Christiaan Huygens in March 1655, and is the only moon to possess a dense atmosphere comprised of a thick haze that cameras in the visible spectrum cannot penetrate. Titan was first explored by NASA’s Pioneer 11 and later by Voyager 1 and 2, but none of the spacecraft possessed the equipment to penetrate the thick atmosphere and see the surface. It wasn’t until NASA’s Cassini mission with its radar and infrared instruments that scientists were able to see the surface for the first time, revealing countless lakes of liquid methane and ethane, making Titan the only known planetary body other than Earth to have bodies of liquid on its surface. During the mission, Cassini deployed the Huygens probe from the European Space Agency that landed on Titan’s surface, becoming the first spacecraft to land on a planetary body in the outer Solar System. As Dr. Barnes stated, NASA’s Dragonfly mission will be sent to Titan to explore the moon’s potential habitability, and will cover hundreds of kilometers of Titan’s surface during two-year mission.
“My favorite moon in the Solar System is Ganymede, simply because it’s a planet by any other name,” said Dr. Paul Byrne, who is an associate professor in the Department of Earth and Planetary Sciences at Washington University in St. Louis. While Dr. Byrne believes that Ganymede would be called a planet if it wasn’t a moon around Jupiter, he’s quick to point out that Ganymede wouldn’t have stayed a planet if it didn’t form around Jupiter in the first place.
“But Ganymede is magnificent,” Dr. Byrne continues. “It’s got a highly geologically complex outer shell of water ice, showing both ancient and relatively recent regions. Beneath that shell is an ocean of liquid water up to 900 kilometers deep. More likely, instead of a single water ocean, there’s a layer of high-pressure ice at the base of a somewhat thinner ocean. In fact, it’s even possible that there are interleaved layers of ocean and ice, forming an onion-like interior beneath the icy exterior. And then, under all the ice and water is a rocky planetary body about the same size of the Moon. And that rocky body must surely be differentiated, just like the Moon, and Earth, Venus, Mars, and Mercury—because the rocky interior of Ganymede has at its center a liquid iron core, the movement of which generates a modern magnetic field. That field makes Ganymede one of only three rocky bodies in the Solar System to generate a modern magnetic field, the other two being Earth and Mercury. There are lots of other cool things about Ganymede, but it’s its size, interior structure, and modern magnetic field that together fascinate me, and make it my favorite Solar System moon.”
Much like Io and Europa, Jupiter’s third Galilean moon, Ganymede, was also discovered by Galileo Galilei in 1610, and is the largest moon in the Solar System, even bigger than the planet Mercury and the dwarf planet Pluto. Ganymede was first visited by NASA’s Pioneer 10 and then Pioneer 11, but received its first up close study from Voyager 1 and 2 in 1979, with Voyager 1 imaging a surface that had a combination of craters and smooth terrain, which contrasts both Io and Europa’s respective surfaces. NASA’s Galileo spacecraft became the first spacecraft to orbit Jupiter and was able to provide the most in-depth analyses of Ganymede, including the identification of a magnetosphere that Dr. Byrne mentions, along with up close images revealing a very diverse surface. NASA’s Hubble Space Telescope, which is in Earth orbit, later provided evidence that Ganymede harbors an interior ocean much like Europa.
What are your favorite moons of the Solar System and which do you think will be the first to confirm the existence of life beyond Earth?
As always, keep doing science & keep looking up!
The post The Favorite Solar System Moons of Planetary Geologists; An In-Depth Discussion appeared first on Universe Today.
Remnants of a Relict Glacier Found Near the Equator on Mars
by Evan Gough on March 20, 2023 at 8:32 pm
New results presented at the 54th Lunar and Planetary Science Conference could change our approach to Mars exploration. Scientists studying the surface of Mars discovered a relict glacier near the planet’s equator. The relict glacier could signal the presence of buried water ice at the planet’s mid-latitudes.
Some areas of the Martian surface are known for light-toned deposits (LTDs.) NASA’s Viking spacecraft spotted them in the late 1970s. Since then, scientists have found them in Valles Marineris, Hebes Chasma, and in other locations on Mars. Their unusual features have captured the attention of researchers who want to understand how they formed.
While LTDs are named for their colour, that’s not the only way they differ. Their surfaces can set them apart from their surroundings, too. The top of LTDs can be rough, in contrast to their smooth-surfaced surroundings.
As scientists have worked to piece together Mars’ geological history, they’ve tried to understand what exactly LTDs are and where they fit in the timeline. In a 2008 paper, researchers presented evidence that some LTDs are vestiges of large-scale spring deposits.
Different teams of researchers have examined the LTDs and reached different conclusions. Some concluded that they’re lacustrine deposits, some suggested they’re made of deposits eroded from walls, some thought they’re aeolian deposits, and some even suggested that they’re volcanic deposits.
But as time has passed, scientists learned that LTDs typically consist of lightly-coloured sulphate salts, which means water was involved with their formation. In the newly-released paper, the authors focused on an LTD in Eastern Noctis Labyrinthus. That LTD has some intriguing surface features similar to a glacier, including moraine bands and crevasse fields.
The new paper is “A RELICT GLACIER NEAR MARS’ EQUATOR: EVIDENCE FOR RECENT GLACIATION AND VOLCANISM IN EASTERN NOCTIS LABYRINTHUS.” It’s published by the SETI Institute, and the lead author is Dr. Pascal Lee, a planetary scientist at the SETI Institute.
“What we’ve found is not ice, but a salt deposit with the detailed morphologic features of a glacier. What we think happened here is that salt formed on top of a glacier while preserving the shape of the ice below, down to details like crevasse fields and moraine bands,” said Dr. Lee.
The region is blanketed in volcanic material, and that’s a clue to what happened here. When pyroclastic materials, including ash, pumice, and lava, erupted from volcanoes, they landed on top of the ancient glacier. When they contacted the ice, chemical reactions would’ve occurred that formed a thick layer of sulphate salts like the ones in Mars’ LTDs. The sulphate salts would’ve formed a hardened layer moulded to the surface of the ice.
Over long periods of time, the volcanic material covering the glacier eroded. What’s left is the layer of sulphate salts, preserving the form of the original underlying glacier.
“This region of Mars has a history of volcanic activity. And where some of the volcanic materials came in contact with glacier ice, chemical reactions would have taken place at the boundary between the two to form a hardened layer of sulphate salts,” explains Sourabh Shubham, a graduate student at the University of Maryland’s Department of Geology, and a co-author of the study. “This is the most likely explanation for the hydrated and hydroxylated sulphates we observe in this light-toned deposit.”
That explains the chemistry behind the formation of the sulphate layer. And the morphology of the layer points to an underlying glacier at the time the sulphate layer formed.
“Glaciers often present distinctive types of features, including marginal, splaying, and tic-tac-toe crevasse fields, and also thrust moraine bands and foliation. We are seeing analogous features in this light-toned deposit in form, location, and scale. It’s very intriguing,” said John Schutt, a geologist at the Mars Institute, experienced icefield guide in the Arctic and Antarctica, and a co-author of this study.
Over time, craters have impacted the region, but only lightly. That means the features are geologically young, likely from Mars’ Amazonian Age, the most recent age that also includes modern Mars.
“We’ve known about glacial activity on Mars at many locations, including near the equator in the more distant past. And we’ve known about recent glacial activity on Mars, but so far, only at higher latitudes. A relatively young relict glacier in this location tells us that Mars experienced surface ice in recent times, even near the equator, which is new,” said Lee.
There’s no surface ice here. The ice in the glacier may have all sublimated, or some of it might persist under the sulphate cap.
“Water ice is, at present, not stable at the very surface of Mars near the equator at these elevations. So, it’s not surprising that we’re not detecting any water ice at the surface. It is possible that all the glacier’s water ice has sublimated away by now. But there’s also a chance that some of it might still be protected at shallow depth under the sulphate salts,” said Lee.
The idea is not without precedent. There are places on Earth where a sulphate cap has protected ice underneath it. The Altiplano Flats in South America contain ancient buried glacier ice sheltered from evaporation, sublimation, and melting by a thick layer of bright salts called salars, according to the authors.
This work isn’t only about unlocking some of the secrets of Mars’ past. It’s also about a future human mission to Mars and where one might land. The authors describe a broad region on Mars between Valles Marineris and Noctis Labyrinthus and north of Oudemans crater, where the relict glacier is located. It’s a topographically depressed region that so far has no official name but contains rich geology. The region has “… a complex aqueous, volcanic, and glacial evolutionary history,” according to the authors.
The region containing the relict glacier has an unofficial name: Noctis Landing. That’s because it’s a potential landing site for a future mission. Because of its rich geological diversity, Noctis Landing is also a potential exploration zone.
The unofficially-named Noctis Landing is situated in a desirable area for exploration. A mission to Noctis Landing could put the Valles Marineris region within reach and expose its extensive geological history to in-situ science. It could also put the Tharsis Montes region within reach, with its volcanic features and its many lava caves.
This highlights the importance of the findings, and it all comes down to water. Water is the key to any human presence on Mars.
In recent years, scientists have uncovered evidence of sub-surface water or water ice on Mars. Radar signals suggest the presence of buried lakes under the planet’s south pole. Follow-up studies suggested that the signals might not be from buried water. Other research suggested that there’s so much water available we wouldn’t have to dig far to access it. The topic of Martian water is still debated.
But if there is water ice under the LTD at Noctis Landing, it could be a very significant finding.
“The desire to land humans at a location where they might be able to extract water ice from the ground has been pushing mission planners to consider higher latitude sites. But the latter environments are typically colder and more challenging for humans and robots. If there were equatorial locations where ice might be found at shallow depth, then we’d have the best of both environments: warmer conditions for human exploration and still access to ice,” said Lee.
If the team’s results are correct and the LTD is a layer of sulphates once married to a glacier, it doesn’t necessarily mean there’s still frozen water somewhere underneath. That has yet to be determined. Studying more LTDs from orbit might find other instances where sulphate has capped glaciers and potentially left behind an icy substrate. Finding more would strengthen these initial results.
There’s a lot more work to do, according to Lee. “We now have to determine if, and how much, water ice might actually be present in this relict glacier, and whether other light-toned deposits might also have, or have had ice-rich substrates.”
A proposed future mission could play an important role in the work yet to be done. The Canadian Space Agency, the Italian Space Agency, the Japanese Aerospace Exploration Agency, and NASA are all developing a mission that would specialize in ferreting out Martian water ice in the planet’s non-polar regions. It’s called the International-Mars Ice Mapper (I-MIM), and at this juncture, it’s only a proposal. The agencies involved call it a “pre-exploration mission,” and it would help pave the way for missions to Mars in the same way that other reconnaissance orbiters have paved the way for MSL Curiosity and the Perseverance Rover.
But the I-MIM would be directly focussed on finding ice in Mars’ middle latitudes. It would search in areas that are less than 2 km in elevation to enable entry, descent, and landing. The mission would focus on latitudes between 25 and 40, both north and south. Solar arrays are more efficient away from the poles, while the increased solar insolation at the equator contra-indicates ice. Its goal would be to find water ice that’s within 5 to 10 meters of the surface and is accessible to astronauts.
There’s no set date or timeline for the I-MIM. But if and when it launches and starts scanning Mars for buried water ice, it’ll be a significant development. It’ll signal a new level of determination to get humans to Mars.
- Press Release: Remains of a Modern Glacier Found Near Mars’ Equator Implies Water Ice Possibly Present at Low Latitudes on Mars Even Today
- Research: A RELICT GLACIER NEAR MARS’ EQUATOR: EVIDENCE FOR RECENT GLACIATION AND VOLCANISM IN EASTERN NOCTIS LABYRINTHUS
- Universe Today: Want to Live on Mars? Here’s Where the Water is
The post Remnants of a Relict Glacier Found Near the Equator on Mars appeared first on Universe Today.