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This Breathtaking Close-Up of Mars’ ‘Grand Canyon’ Is Giving Us Goosebumps

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Tithonium Chasma is one big canyon. At a staggering 810 kilometres (503 miles) long, it’s a large part of Valles Marineris – the biggest canyon system we know of in the whole Solar System.

 

This close-up image of the chasma was taken back in 2013 by the High Resolution Imaging Science Experiment (HiRISE) camera on board the Mars Reconnaissance Orbiter, and was just featured as the HiRISE Picture of the Day. 

The image shows around a kilometre (0.6 miles) of Mars terrain with torturous hills and valleys, but as you can see in the other images, when you start to zoom out, this is just one small section of a gigantic whole.  

ESP 034132 1750 1(NASA/JPL/UArizona)

But how did it get there? The Grand Canyon on Earth – which is five times shallower and 10 times shorter than the Valles Marineris – was carved by the Colorado River.

But scientists aren’t sure what would have formed the 8- to 10-kilometre (5 to 6.2 miles) deep canyon of Valles Marineris and Tithonium Chasma, so they’ve been taking photos to try and find out.

We know that the tilt of Mars’s axis (called the obliquity) is not as stable as Earth’s, ranging widely from over 60 degrees to under 10 in the ancient past.

ESP 034132 1750 RED.browseAn uncropped, uncoloured version of the picture above. (NASA/JPL/UArizona)

“It is possible, though unproven, that higher obliquity triggered partial melting of some of Mars’ water ice,” HiRISE spokesperson Edwin Kite wrote back in 2014.

“Our best chance at understanding this is to find piles of ice, dust, silt or sand that accumulated over many cycles of obliquity change.”

The image of Tithonium Chasma above shows these findings. The sediment layers – those dark and light stripes running diagonally down the middle of the image – are relatively uniform, possibly showing the gradual buildup of sediments over many long cycles of this axial tilt change.

ESP 034132 1750 whereA map showing the location on the Valles Marineris. (NASA/JPL/UArizona)

Even seven years after this photo was taken, we’re still not sure what created the Valles Marineris. Some researchers suspect a large tectonic “crack” may have split Mars’ surface, to be later enhanced by lava flow, or potentially water if the planet’s axial tilt was just right. 

But really, although these images are scientifically interesting to astronomers, they’re also just gorgeous.

The staggering scale of these otherwordly peaks and troughs, captured by a spacecraft 264 kilometres (163.8 miles) from the planet’s surface, really can’t be understated. 

You can see even more pictures of the Valles Marineris here.

 



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NASA Reveals Plans to Buy Fresh Moon Dust For Just $1

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The US space agency NASA awarded contracts to four companies on Thursday to collect lunar samples for US$1 to US$15,000, rock-bottom prices that are intended to set a precedent for future exploitation of space resources by the private sector.

 

“I think it’s kind of amazing that we can buy lunar regolith from four companies for a total of $25,001,” said Phil McAlister, director of NASA’s Commercial Spaceflight Division.

The contracts are with Lunar Outpost of Golden, Colorado for US$1; ispace Japan of Tokyo for US$5,000; ispace Europe of Luxembourg for US$5,000; and Masten Space Systems of Mojave, California for US$15,000.

The companies plan to carry out the collection during already scheduled uncrewed missions to the Moon in 2022 and 2023.

The firms are to collect a small amount of lunar soil known as regolith from the Moon and to provide imagery to NASA of the collection and the collected material.

Ownership of the lunar soil will then be transferred to NASA and it will become the “sole property of NASA for the agency’s use under the Artemis program.”

Under the Artemis program, NASA plans to land a man and a woman on the Moon by 2024 and lay the groundwork for sustainable exploration and an eventual mission to Mars.

“The precedent is a very important part of what we’re doing today,” said Mike Gold, NASA’s acting associate administrator for international and interagency relations.

 

“We think it’s very important to establish the precedent that the private sector entities can extract, can take these resources but NASA can purchase and utilize them to fuel not only NASA’s activities, but a whole new dynamic era of public and private development and exploration on the Moon,” Gold said.

“We must learn to generate our own water, air and even fuel,” he said. “Living off the land will enable ambitious exploration activities that will result in awe inspiring science and unprecedented discoveries.”

Any lessons learned on the Moon would be crucial to an eventual mission to Mars.

“Human mission to Mars will be even more demanding and challenging than our lunar operations, which is why it’s so critical to learn from our experiences on the Moon and apply those lessons to Mars,” Gold said.

“We want to demonstrate explicitly that you can extract, you can utilize resources, and that we will be conducting those activities in full compliance with the Outer Space Treaty,” he said. “That’s the precedent that’s important. It’s important for America to lead, not just in technology, but in policy.”

The United States is seeking to establish a precedent because there is currently no international consensus on property rights in space and China and Russia have not reached an understanding with the United States on the subject.

The 1967 Outer Space Treaty is vague but it deems outer space to be “not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.”

© Agence France-Presse

 



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Incredible Images Reveal a Mysteriously Formed Triple Crater on Mars

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In its 4.6 billion-year-long history, Mars has taken its fair share of punches from hurtling asteroids and careening comets. 

Today, the surface of the red planet is covered in no less than 43,000 impact craters larger than 5 kilometres; some ancient regions have received more of a beating than others.

 

In the ancient Martian highlands of Noachis Terra – a region heavily impacted roughly 4 billion years ago – astronomers have spotted a triple whammy crater made of three overlapping basins.

This natural Venn diagram of depressions is not as big as some other craters in Noachis Terra, some of which can span nearly nearly 140 km (87 miles) across, but the smallest crater of the lot is still an impressive 28 kilometres wide.

And that’s just one of the ancient imprints. With a little overlap, the largest adds another 45 km across.

In context Triple crater east of Le Verrier pillarsThe triple crater imaged by the Mars Express High Resolution Stereo Camera (HRSC).

Whether the triple impact crater is due to one collision or more is hard to tell. Researchers say the impactor may have broken into three pieces before hitting the ground in close formation, but other examples of this shatter approach do not show such clear ridge definitions, nor are they so neatly overlapped.

Double and triple impact craters are unusual to see but they are not unheard of; we occasionally find them on Mars and even on Earth, although not all of them are formed in the same way.

In 2015, for instance, astronomers noticed a similar triple crater in Elysium Planitia near the equator of Mars (depicted below). At the time, the team surmised it could be due to an asteroid breaking up in the atmosphere, or it could be due to a smaller asteroid orbiting a larger binary pair.

ESP 039147 1940 2Triple impact crater in Elysium Planitia. (NASA/JPL-Caltech/University of Arizona)

In 2017, the Mars Reconnaissance Orbiter noticed an elongated depression from three merged impact craters, which astronomers said probably came from three pieces flying in close formation.

Some have also postulated that double craters are due to double asteroids, composed of two or more rocky bodies in close contact or closely orbiting each other. Only about 2 percent of all asteroids are thought to form from two or more bodies like this, but that doesn’t mean they can’t sometimes collide with a planet and leave a scar.

 

“Another explanation could be coincidence,” reads a press release on the latest triple impact crater, this time from the European Space Agency, “at different points in time, three separate impactors could have hit Mars’ surface in this location, creating a neat superposition of craters completely by chance.”

Given how heavily bombarded this region of Mars once was, experts say that’s the likelier possibility, although it’s hardly the more interesting one.

Mars Express spies an ancient triple crater on Mars(ESA/DLR/FU Berlin/CC BY 3.0)

If, on the other hand, this isn’t due to three chance encounters, and the impactor really did break apart before hitting Mars, that tells us something important about this planet: 4 billion years ago, the atmosphere of Mars was likely a lot tougher to penetrate than it is now, and that implies warmth and wetness.

Similar to other craters in the region, this triple impact crater shows flattened rims and shallow floors from the wear and tear of time. Some of its marks even suggest a glacier-like flow, which may have helped soften the soil underneath, gradually filling the indentation as the ice melted.

Like scars often do, this one speaks volumes of the past.

 



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Ancient Meteorite Hints Mars Had Water Before There Was Life on Earth

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We know that Mars was once much wetter than it is now, but the questions of when water formed and evaporated away are much more difficult to answer.

A new study now suggests that water was present on the Red Planet some 4.4 billion years ago, much earlier than previously thought.

 

That’s based on an analysis of a meteorite named NWA 7533, picked up in the Sahara Desert and thought to have originated on Mars billions of years ago. The oxidation of certain minerals inside the meteorite hints at the presence of water.

The findings could push back the estimated date of water formation on Mars some 700 million years, from the 3.7-billion-years-ago timeframe that has been the general consensus up until now. The research could also offer up some insights into how planets form in the first place.

“I study minerals in Martian meteorites to understand how Mars formed and its crust and mantle evolved,” says planetary scientist Takashi Mikouchi from the University of Tokyo in Japan.

“This is the first time I have investigated this particular meteorite, nicknamed ‘Black Beauty’ for its dark colour. Our samples of NWA 7533 were subjected to four different kinds of spectroscopic analysis, ways of detecting chemical fingerprints. The results led our team to draw some exciting conclusions.”

Planetary scientists are keenly interested in the story of water on planets and on moons. One of the big unknowns is whether water gets added to a planetary body after it forms, through the impacts of asteroids and comets, or whether it occurs naturally during the planet formation process.

 

Ancient rocks like NWA 7533 can help scientists peer back in time and find out, as they record impact events on the planet they come from, and capture some of the mineral and chemical composition of the surface when they are formed.

In this case, it’s the oxidation that’s the tell-tale sign of water. With certain fragments inside NWA 7533 dated to 4.4 billion years ago, it’s the oldest record we’ve got of Mars (which may be why a single gram of this meteorite can fetch as much as US$10,000).

“Igneous clasts, or fragmented rock, in the meteorite are formed from magma and are commonly caused by impacts and oxidation,” says Mikouchi. “This oxidation could have occurred if there was water present on or in the Martian crust 4.4 billion years ago during an impact that melted part of the crust.”

Such an early appearance suggests that water actually was around when Mars formed and that in turn plays into research into planetary formation in general. With water comes life, which is one reason scientists are so eager to track it down around the Universe. For comparison, we know that the earliest traces of life on Earth date to at least 3.5 billion years ago.

The close study of Mars continues as experts try and figure out when water was present and what form it might have taken. One recent study put forward the idea that both liquid water and surface ice could have existed on the Red Planet at the same time.

The team’s findings also suggest that the chemical make-up of the Martian atmosphere at this time – including high levels of hydrogen – could have made the planet warm enough for water to melt and life to exist, even though the Sun would have been younger and fainter during this period.

“Our analysis also suggests such an impact would have released a lot of hydrogen, which would have contributed to planetary warming at a time when Mars already had a thick insulating atmosphere of carbon dioxide,” says Mikouchi.

The research has been published in Science Advances.

 



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An Asteroid Trailing After Mars Could Actually Be The Stolen Twin of Our Moon

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A distant asteroid trailing in the gravitational wake of Mars has been observed in greater detail than ever before, and the close-up reveals a surprising resemblance – one that raises some interesting questions about the object’s ancient origins.

 

The asteroid in question, called (101429) 1998 VF31, is part of a group of trojan asteroids sharing the orbit of Mars.

Trojans are celestial bodies that fall into gravitationally balanced regions of space in the vicinity of other planets, located 60 degrees in front of and behind the planet.

Most of the trojan asteroids we know about share Jupiter’s orbit, but other planets have them too, including Mars and Earth too.

What makes (101429) 1998 VF31 (hereafter ‘101429’) interesting is that among the Red Planet’s trailing trojans (the ones that follow behind Mars as it orbits the Sun), 101429 appears to be unique.

010 moon asteroid 2Depiction of Mars and trojans; 101429 is the blue point circling L5. (AOP)

The rest of the group, called the L5 Martian Trojans, all belong to what’s known as the Eureka family, consisting of 5261 Eureka – the first Mars trojan discovered – and a bunch of small fragments believed to have come loose from their parent space rock.

101429 is different, though, and in a new study led by astronomers from the Armagh Observatory and Planetarium (AOP) in Northern Ireland, researchers wanted to examine why.

 

Using a spectrograph called X-SHOOTER on the European Southern Observatory’s 8-m Very Large Telescope (VLT) in Chile, the team examined how sunlight reflects off 101429 and its L5 kin in the Eureka family. Only, it looks like 101429 and the Eureka clan aren’t kin after all, with the analysis revealing 101429 shows a spectral match for a satellite much closer to home.

“The spectrum of this particular asteroid seems to be almost a dead-ringer for parts of the Moon where there is exposed bedrock such as crater interiors and mountains,” explains AOP astrochemist Galin Borisov.

While we can’t be sure yet why that is, the researchers say it’s plausible that this Martian trojan’s origins began somewhere far removed from the Red Planet, with 101429 representing a “relic fragment of the Moon’s original solid crust”.

If that’s true, how did the Moon’s long-lost twin end up as a trojan bound together with Mars?

010 moon asteroid 2Spectral comparison of 101429 and the Moon’s surface. (AOP)

“The early Solar System was very different from the place we see today,” explains lead author of the study, AOP astronomer Apostolos Christou.

“The space between the newly-formed planets was full of debris and collisions were commonplace. Large asteroids [planetesimals] were constantly hitting the Moon and the other planets. A shard from such a collision could have reached the orbit of Mars when the planet was still forming and was trapped in its Trojan clouds.”

 

It’s a captivating idea, but the researchers say it’s not the only explanation for 101429’s past. It’s also possible, and perhaps more likely, that the trojan instead represents a fragment of Mars chipped off by a similar kind of incident impacting the Red Planet; or it might just be a commonplace asteroid that, through the weathering processes of solar radiation, ended up looking just like the Moon.

Further observations with even more powerful spectrographs might be able to shed more light on this question of space parentage, as could a future spacecraft visit, the team says, “which could, en route to the Trojans, obtain spectra at Mars or the Moon for direct comparison with the asteroid data”.

The findings are reported in Icarus.

 



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Elon Musk’s SpaceX Now Wants to Impose Its ‘Own Legal Regime’ on Mars

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SpaceX may try impose its “own legal regime” on Mars and form a “self-governing”, self-sustaining settlement where Earth laws wouldn’t apply.

Though this may sound like a page taken out of a sci-fi novel, Elon Musk‘s aerospace company has indicated its intentions to do just that in two recent and remarkable posts.

 

The first is a wide-ranging Law360 interview with SpaceX general counsel David Anderman, who revealed he’s drafting a constitution for Mars. The second is the terms of service for Starlink, SpaceX’s new satellite-internet project, which Reddit users shared after receiving a public beta test invitation.

But to get Earth to recognise the sovereignty of any would-be Martian state, SpaceX will have to pull off some astounding diplomacy and changes to international law, says Frans von der Dunk, a leading expert of space law at Nebraska College of Law.

“You can come up with many interesting examples where you have people trying to call themselves a state and not being recognised,” von der Dunk told Business Insider.

Still, he thinks the international community should take SpaceX and its founder Elon Musk seriously – and use the moment to work out potential legal quandaries of such a fantastic human future before they’re made real.

“We never know if it’s going to work or when it’s going to work,” von der Dunk said of SpaceX’s planned Martian settlement. “But this is certainly a serious company with serious backing and serious engineering behind it.”

5fa047d16f5b310011724dadElon Musk’s vision of Starship enabling the buildup of a city on Mars. (SpaceX)

The parties recognise Mars as a free planet

Musk has for many years shared his dream of populating Mars with more than a million people. Though he wants to create cities complete with bars and pizza joints – and quickly – the tech mogul’s ultimate goal is “enabling human life on Mars,” ideally to back up our species from some indeterminate future catastrophe.

To that end, SpaceX has expanded its facilities in South Texas to develop and test Starship, a nearly 400-foot-tall (122-meter-tall) steel launch system that’s fully reusable.

 

If it works as intended, the cost of flying anything to space could shrink 100- to 1,000-fold. In line with that effort, the company has begun mulling its legal approach to rocketing colonists en masse to the Red Planet.

“Our goal is to be able to send 1,000 starships with 100 people in them every two years,” Anderman told Law360, which published its interview on October 14.

“We’ll start with 100, then a couple hundred, then 100,000, then a million until we have a truly sustainable colony. It will happen in my lifetime. Faster than you think.”

When asked if US law would govern such a settlement, Anderman revealed he’s helping draft “a constitution for Mars.”

“I think SpaceX will move to impose our own legal regime. I think it will be interesting to see how it plays out with terrestrial governments exerting control,” he added.

“I do think we are going to have a pretty important role to play in what works and what laws apply.”

About two weeks after that interview ran, several Reddit users posted the terms of service for Starlink. The text contained most of what one would expect from a mundane internet service provider agreement.

 

Yet in a section about which laws would govern use of Starlink, the document stated the following:

“For Services provided on Mars, or in transit to Mars via Starship or other colonisation spacecraft, the parties recognise Mars as a free planet and that no Earth-based government has authority or sovereignty over Martian activities. Accordingly, Disputes will be settled through self-governing principles, established in good faith, at the time of Martian settlement.”

In effect, SpaceX has signalled its diplomatic intentions to make its Martians rule themselves. However, von der Dunk says the company won’t pull that off without extraordinary effort on Earth.

SpaceX did not immediately acknowledge Business Insider’s request for comment.

Right now, the US would be responsible for SpaceX’s Mars settlement

Mars is an average of 158 million miles away from Earth, making the idea of enforcing laws made on Earth, for Earth there seem potentially laughable (despite the existence of a US Space Force).

Still, the Outer Space Treaty of 1967, to which 110 nations are currently party – including spacefaring ones like China, India, Russia, and the US – dictates that people who leave Earth carry their national identities with them.

 

“If [SpaceX] succeeds in building settlements, [Musk] and the people living there, certainly if they are Americans, will still be falling under the US jurisdiction,” von der Dunk said.

“Not because it’s US territory, but because they are US citizens.”

Additionally, Article 6 and Article 7 of the treaty make clear that a country bears the legal burden of its space activities no matter who launches or performs them. Because SpaceX is an American company operating under American licenses, the US would have to assume liability for SpaceX’s hardware and actions.

“Imagine if [SpaceX does] something that other states could claim are violation of international law,” von der Dunk said.

“They don’t need to try and sue SpaceX before a US court in a private capacity; they can directly accost the US government.”

So if anything bad happens at SpaceX’s Martian settlement, the company could feel the squeeze back on Earth, to the point of potentially interfering with its settlement plans.

Von der Dunk also says “there is no clear-and-fast guideline as to when you are state,” but he noted international law does settle around three objective criteria: established territory, a permanent population, and a functional government.

Any would-be Mars settlement would presumably fulfil the latter two requirements.

But von der Dunk says the first is impossible to check off as laws are currently written. (He noted the “space kingdom” Asgardia, which announced its purported plans to create a nation-state in open space, is even more subject to this problem.)

Specifically, Article 2 of the Outer Space Treaty eschews the idea of owning territory beyond Earth, mainly to prevent nations from claiming land on heavenly bodies simply by landing probes there.

“That’s what the Outer Space Treaty clearly prohibits,” von der Dunk said. “It never thought about the possibility that you’d create a state entirely in outer space.”

(SpaceX/Twitter)(SpaceX/Twitter)

It is important to keep an eye on these things

Von der Dunk says Earth’s nations could move to change or do away with Article 2, or perhaps craft some legal loophole to permit SpaceX to form a self-governing Martian settlement.

“But I think it would be a very difficult exercise, and it certainly won’t happen soon,” he added. “And, as you can imagine, if this is more likely either a US territory or a territory of US citizens who then create their own new state, countries like China and Russia may not be very sympathetic to the idea.”

And that leads to what von der Dunk described as a subjective and “murky” fourth requirement: International recognition of a new state.

“I think, at the end of the day, it all boils down to whether or not the rest of the world, in particular the major spacefaring nations, would agree to that,” he said.

Two historical examples of the world struggling to accept a new nation stand out, he added.

First there’s Taiwan, which technically fulfils all three of the objective criteria of a state – it has territory, a permanent population, and its own government. But on the world stage, China and others dispute the independence of Taiwan, and it has no seat at the United Nations.

There’s also the United States. In 1776, when a young and scrappy coalition of colonies declared their independence from British rule, a number of countries declined to recognise the fledgling and war-torn nation. This changed during and after the American Revolutionary War, which ended in 1783.

So while it’s not impossible for SpaceX to form a sovereign Martian state recognised by Earth’s nations, von der Dunk said the bar remains high with changing Article 2 and earning international recognition of sovereignty.

“Neither of them are, by their own nature, eternal. So I can’t completely exclude that, 50 years from now, we will have a state on Mars,” he said.

For that reason, and the fact that SpaceX is a corporation, Von der Dunk said it’s important to take seriously the company’s plans and work to develop sensible regulation – even if it seems unlikely Musk will ever get his cities on the red planet.

“SpaceX is a private company, and they want to make money,” he said.

“It is important to keep an eye on this and to generate international discussions and to make sure things are going in the right [direction] – that you do not get a settlement on Mars which turns out to be totally reckless and without any regard for what we, on Earth, consider in the overarching interest of humanity.”

This article was originally published by Business Insider.

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This Martian Lava Tube Could Swallow Earth’s Biggest Lava Tube More Than 3 Times

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NASA’s Mariner 9 was the first spacecraft to orbit another planet when it reached Mars in late 1971. It got there only a few weeks before the Soviet Union’s Mars 2 and Mars 3 spacecraft, despite being launched 11 days later than those missions. Unfortunately, there was a major dust storm when Mariner 9 arrived, and NASA had to wait until January before the spacecraft could get good images.

 

When it did get those images, they revealed a surprise: volcanoes and lava flows cover large portions of the Martian surface.

In the decades since Mariner 9’s visit, we’ve learned a lot about Mars and its geologic history. For instance, we know that Mars is home to the Solar System’s largest volcano: Olympus Mons.

But volcanoes and lava flows are just the most visible artifacts of Mars’ ancient volcanic activity. As our technology has gotten better and better, we’ve been able to see the surface in greater detail. And that’s revealed the presence of lava tubes on the planet.

Lava tubes form when lava flows underneath the surface. As the outside of the flowing lava cools and solidifies into a ceiling and walls, the interior stays molten and keeps flowing. Eventually, the lava flows out of the tube in a downslope direction, leaving the tube.

Lava tubes, also called pyroducts, can be found on Earth, the Moon, and Mars. They may be found on other bodies that have volcanic activity, too.

But while Earth is larger than Mars, terrestrial lava tubes are smaller than the largest ones on Mars. The HiRISE (High-Resolution Imaging Science Experiment) camera on NASA’s Mars Reconnaissance Orbiter (MRO) recently took a picture of a collapsed lava tube ceiling that is much larger than anything on Earth.

 

When HiRISE took this image, shadows prevented it from seeing inside the collapsed section, sometimes called a skylight. But if the hole is 50 meters across, the lava tube is likely that large,too. On Earth, lava tubes are only as large as 14–15 meters (46–49 ft) wide, though they’re typically much narrower.

Some scientists say that exploring lava tubes should be given some priority. Lava tubes could host any simple life that may have survived to this day on Mars. As the planet lost its atmosphere and cooled, the tubes could’ve provided shelter from the increasingly hostile surface conditions. If life had migrated there somehow, it may still be present.

Science journalist Sid Perkins thinks so. In his article “Core Concept: Lava tubes may be havens for ancient alien life and future human explorers,” he said, “If Mars ever hosted life, it may have moved into such refugia as the planet evolved and surface conditions became increasingly harsh. Indeed, some researchers suggest that microbial life may yet hang on in the Red Planet’s underground havens.”

If those underground havens are good enough for Martian microbial life, they may be good enough for humans. Some researchers say that habitats or bases could be placed or built inside these tubes. In the same way that they could potentially provide shelter for extant Martian life, they could provide shelter for visiting humans on the Moon, or possibly even on Mars itself.

“Lava tubes could provide stable shields from cosmic and solar radiation and micrometeorite impacts which are often happening on the surfaces of planetary bodies,” said Francesco Sauro, co-author of a comparative study of lava tubes on Earth, Mars, and the Moon. “Moreover, they have great potential for providing an environment in which temperatures do not vary from day- to night-time.”

PersonStandsInsideStefanshellirLavaTubeA person stands inside the the Surtshellir-Stefanshellir lava tube. (Dave Bunnell/Under Earth Images/Wikimedia Commons/CC BY 4.0)

But before we use them for that purpose, we have to explore them first. And though there’s a strong likelihood that they’re similar to tubes on Earth, nobody’s really seen inside one yet. There are images that show a portion of the floor of these tubes, but that’s it.

If we’re going to explore them, it’ll be risky. Astronauts on the Moon or on Mars are not going to be set up to go spelunking, or to belay each other down into the hole. There are probably some people who would dedicate their entire adult life to being the first to go into one, but space agencies are reluctant to put people in that kind of danger.

 

It’ll probably be up to machines to do the initial exploration. And scientists have already put some thought into that. One concept is the Moon Diver.

The Moon Diver is the brainchild of NASA’s Laura Kerber at JPL. She and her colleagues proposed the mission to explore the Tranquillitatis Pit on the Moon. The proposal included a stationary lander that would land near the pit. Then it would release a small, two-wheeled rover that would approach the pit, and lower itself into it while still tethered to the lander by cable.

Unfortunately, the Moon Diver was not chosen for funding. But the idea is still alive.

There are currently no plans to explore lava tubes on Mars or the Moon. But it might just be a matter of time until we do. Compared to some of the missions proposed to explore Titan and Europa, for example, a mission similar to the Moon Diver might not be that complex, or expensive.

But until then, they’re tantalizing targets for cameras.

This article was originally published by Universe Today. Read the original article.

 



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NASA Finds Billion-Year-Old Sand Dunes Preserved on Mars, And They Look Familiar

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Tucked away in a canyon on Mars, scientists have discovered a windswept field of solid sand, which turned to rock roughly a billion years ago.

Despite being heavily eroded, this frozen plain of palaeo-dunes has withstood time remarkably well, much more so than fossilised waves of sand on Earth, which are subject to the whims of wind, water, and the shifting landscapes of deep time.

 

Understanding how these duneforms stood the test of time could give us insight into the sedimentary processes on Mars and reveal something about the planet’s geologic history at the same time. 

“This level of preservation is rare for terrestrial sand dunes due to ongoing erosion and tectonics,” explains planetary scientist Matthew Chojnacki from the Planetary Science Institute. 

“Based on the dune deposit’s relationships to other geologic units and modern erosion rates we estimate these to be roughly a billion years old.”

Mars sand dune discovery HiRISE 2020(NASA/JPL/University of Arizona)

Today on Mars, sand dunes, whipped up by wind, are a common feature, and the size and arrangement of those fixed in place in the widest part of the Valles Marineris canyon – the Melas Chasma – look remarkably similar to ones formed more recently.

This suggests the climate and atmosphere on Mars has changed little in a very, very long time. Astronomers say the orientation, length, height, shape and slope of the Melas Chasma palaeo-dunes all resemble recently-made waves of sand seen elsewhere on the Red Planet.

“This indicates the major wind directions that are responsible for the dunes’ shape have not changed substantially over time,” Chojnacki told EarthSky.

 

“We also see very similarly sized and spaced sand dunes from the two time periods. This may indicate the atmospheric pressure wasn’t significantly different.”

Using images from the High Resolution Imaging Science Experiment (HiRISE) and Martian topography data, researchers have documented and dated the bedform properties of Melas Chasma. 

Although the topography of this canyon is still incomplete, as some of the dunes have eroded away or been buried, the paleo-dunes we can decipher “do not paint a dramatically different picture than what can be gained from their modern counterparts,” the researchers explain.

The authors found some dunes were buried under tens of metres of material, which appeared to come from a catastrophic volcanic event.

image 11(Chojnacki et al., JGR Planets 2020)

Sometime afterwards, the authors predict, a volatile compound came into contact with the compacted sand dunes and helped harden them, freezing the waves in time as they migrated across the Melas Chasma.

This same sort of process can be seen on Earth when groundwater invades a partially buried sand dune – formed layers of lithified sand like those famous striped structures seen in Zion National Park. Unlike our planet, however, lithified sand dunes on Mars have far fewer elements to contend with.

In the absence of water, vegetation or plate tectonics, exposure to trade winds is the main eroder on Mars, and over deep time, this has helped chisel back the volcanic shell that once covered these dunes.

HiRISE martian dunes 1Close up of sand dunes taken by HiRISE Camera. ( NASA/ JPL-Caltech/University of Arizona)

The mere existence and degree of preservation seen in these dunes indicates an important difference in the landscape evolution of Earth and Mars. 

While ancient lithified sand dunes on Earth are rare to find and much more eroded, the Melas Chasma appears to possess “extensive paleo-dune fields scattered across the basin floor, where many duneforms and their morphology appear largely intact.”

“Water and tectonics that constantly reshape the surface of Earth are not currently a factor on Mars, thus there is an opportunity to learn from the geologic record of the red planet,” says Chojnacki.

“These results inform us that wind-driven sand transport, deposition, and lithification have occurred throughout much of Mars’ recent history and illustrate how landscape evolution there greatly differs compared to that of Earth.” 

The study has been published in JGR Planets.



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This Week, Mars Is The Closest to Earth It’ll Be For Another 15 Years

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Mars, our second closest cosmic cousin, has been in our collective imagination for decades. Between fantasies of martian visits and the promise of water under its icy surface, Mars doesn’t need to do much to be in our collective good books.

 

But very soon, Mars is not just going to be close to our hearts, but also nearest to our actual planet –  a mere 62.1 million kilometres (38.6 million miles) away from Earth.

This is the closest it’ll be for the next 15 years. And it means that stargazing is highly recommended as Mars will be bright, big and easy to see with or without a telescope.

We’d recommend checking out a sky chart to work out where Mars will be in the night sky in your location so you can plan for the best viewing.

But the good news is, it’ll be in a region of the night sky with very few stars, and if you’re lucky, you should also be able to catch Jupiter and Saturn shining brightly closer to the horizon.

The day we’ll be the absolute closest to Mars is the 6 October, so get a move on.

As you can see in this video below, Mars and Earth are both on slightly elliptical orbits, which means they can occasionally get very close to each other.

 

The closest possible encounter is when Earth is the furthest away from the Sun (aphelion) and Mars is the closest to the Sun (perihelion). At this point the two would be at the minimum 54.6 million kilometres (33.9 million miles) apart.

This configuration is called an opposition, and it happens every two years or so. But we’ve never actually recorded us hitting that perfect ‘closest’ point.

The closest approach we’ve ever recorded happened back in 2003, with just 55.7 million kilometres separating us with Mars. Two years ago, 2018 was pretty close too, with just 57.6 million kilometres (35.8 million miles) between us.

Unfortunately though, we’re getting further and further out of alignment with our closest neighbour and won’t start getting closer again until 2029, culminating in a very close approach in 2035 – only 56.9 million kilometres (35.4 million miles) apart – so start planning your 2035 Mars watching schedule well in advance!

At the other end of the scale from an opposition is a conjunction, when the two planets are furthest from each other. They can end up a 401 million kilometres (250 miles) away from each other. This occurs when Earth and Mars are on opposite sides of the Sun and both in their aphelion.

 

It’s for this reason that space organisations take advantage of the short distance between our planets when these windows arise. This year was a peak opportunity for many missions to the Red Planet.

If you remember, Mars One planned to launch a Mars lander in 2020 before it um, never did that.

But three missions did successfully take off. NASA’s Perseverance rover is close to half way through its journey to the red planet after blasting off back in July, while two other missions left for Mars in the same two-week window.

The next lot of Mars missions – like the Mars Sample Return – will be travelling in 2022, but they’ll have to travel an extra 20 million kilometres, as we’ll be at a distance of 81.5 million kilometres (50.6 million miles) at our closest approach during this time.

So this week is a pretty special opportunity that we won’t have again until 2035. Make sure you wave to Mars as it goes past!



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A Network of Hidden Lakes Has Been Found Under The Surface of Mars, Scientists Say

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The surface of Mars is renowned for its aridity. The entire planet is a dusty, barren desert – a wasteland of rock and, in some regions, ice; but of liquid water, not a confirmed drop has been found.

 

But in 2018, scientists unveiled a bombshell discovery – they’d found evidence of a colossal underground reservoir of liquid water at the Martian south pole.

Now, they’ve taken that discovery a crucial step forward. There’s not one, but an entire network of multiple lakes under the southern polar ice cap. And that means that the first reservoir was not a one-off or a freak of Martian nature.

“The existence of a single subglacial lake could be attributed to ad-hoc conditions such as the presence of a volcano under the ice sheet, or some other situation unique to the specific location where we found the first subglacial lake,” explained geophysicist Elena Pettinelli of Roma Tre University in Italy to ScienceAlert. She led the research alongside colleague Sebastian Emanuel Lauro.

“The discovery of an entire system of lakes instead, suggests their formation process to be relatively simple and possibly common.”

The first subglacial lake was announced just over two years ago. It was discovered using the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on the Mars Express orbiter.

 

This uses the same technique we use to find subglacial lakes in Antarctica – bouncing radio waves off a surface and measuring the echoes, looking for changes in the signal to characterise a topography.

These radar sounding investigations initially revealed a single subglacial lake 1.5 kilometres (0.93 miles) under the southern polar ice cap, measuring 20 kilometres (12.4 miles) across.

“Some types of material reflect radar signals better than others, and liquid water is one of those ‘materials’,” one of the researchers, planetary scientist Graziella Caparelli of the University of Southern Queensland in Australia, told ScienceAlert.

“Therefore, when the signals coming from the subsurface are stronger than those reflected by the surface, we can confirm that we are in the presence of liquid water. Radars are used on Earth (where we can directly verify the results) for the same purpose, so we are certain that the technique is reliable.”

Since then, the team has performed more investigations on a dataset spanning almost a decade, from 2010 and 2019. And, in a new analysis of those data, they found three new brightly reflecting patches.

In other words, a network of subglacial lakes separated by regions of dry stone, hidden away under the south pole, not far from that initial lake.

mars radarMap of the radar data. Blue regions are highly reflective, indicating liquid water. (Lauro et al., Nature Astronomy, 2020)

“In a terrestrial subglacial environment such strong reflections below the ice are associated with the presence of basal water; there are no other physical mechanisms that can generate such a strong anomaly, as far as we know,” Pettinelli said.

“Importantly, we have obtained the same results using more advanced data processing and analysis methods than for our 2018 paper, and the fact that, having run such a rigorous data analysis process, we confirmed the presence of that lake, and found other lakes, makes us quite confident about our interpretation that the liquid is water.”

 

Moreover, if it is liquid water, it’s likely salty water. Extremely salty water. Mars, you see, is very cold, and even though the interior is warmer than the surface, it’s still cold enough to freeze fresh water. In 2018, the team estimated that the lake they found would be around 205 Kelvin (-68.15 degrees Celsius, or -90.67 degrees Fahrenheit).

But salt lowers the freezing point of water, and can do quite significantly. As the team note in their paper, water imbued with salts of calcium and magnesium can remain liquid at temperatures as low as 150 Kelvin, for very long periods of time. And Mars, as we know from exploring the surface, is rich in salts of calcium and magnesium, as well as sodium.

So the discovery of additional salty subglacial lakes is very significant. It means that they can form easily and hang around for geological timescales – which is an important piece in the longstanding puzzle of Mars’ water and climate history. And it also has important implications in the search for Mars microbes.

“These lakes have probably existed for much of Mars’ history,” said planetary scientist Roberto Orosei of the National Institute for Astrophysics in Italy, and principal investigator for MARSIS.

 

“For this reason, they could still retain traces of any life forms that could have evolved when Mars had a dense atmosphere, a milder climate and the presence of liquid water on the surface, similar to the early Earth.”

It’s possible, even, that microbial life may still be thriving in those lakes.

We know that such can live in some of the most salty, inhospitable places Earth has to offer, as well as subglacial reservoirs. Of course, we’re a very, very long way from making such a detection, and studying Mars water up close may contravene the 1967 Outer Space Treaty. But it’s worth thinking about.

The next step the team is taking is to search for water elsewhere on Mars. It’s unclear whether underground reservoirs could exist at lower latitudes, but the north pole has a hefty ice cap of its own.

“It is not implausible that basal lakes also exist beneath the north polar ice cap,” Caparelli said.

“Data analysis of a few data acquired in the same way we acquired those that allowed us to ‘see’ the south polar subglacial lakes has only just begun, however.”

So we’ll be eagerly awaiting to see those results when the team has analysed them. Meanwhile, in an ideal world, Pettinelli would love to send up landers to conduct seismic monitoring to plumb the depths of those reservoirs.

“Active seismic prospecting techniques such as those commonly used on Earth to discover oil reservoirs would be best and have been used in Antarctica to detect the bottom of the lakes. These techniques could shed light on the water depth and the geometry of the water bodies,” she told ScienceAlert.

However, as Mars landers are difficult and expensive, and the seismic monitors would be challenging to set up, we may be waiting a long time for that one.

The research has been published in Nature Astronomy.

 



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