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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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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.”


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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NASA Rover Glimpses a Ghostly Martian Dust Devil Whirling Across The Red Planet

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Mars may have only a thin atmosphere compared to other Solar System planets, but boy does it make the most of it. Water ice can rise high in the sky to form thin clouds. Wild winds can whip up into uncontrolled dust storms that shroud the entire planet, or create dust towers that extend almost into space.


So it should come as no surprise that NASA’s Mars Curiosity rover, beavering away in the Gale Crater, sometimes lays its electronic eyes on Martian weather phenomena – and now, it’s spotted a dust devil spinning across the rocky crater floor.

Seeing weather phenomena on Mars that we also see on Earth isn’t just interesting, though – it can also tell us a lot about seasonal atmospheric changes on the Red Planet.

It’s coming into Martian summer in the planet’s southern hemisphere, where the Gale Crater can be found, and the atmosphere in the region is heating up. Just as uneven heating of the atmosphere on Earth generates atmospheric movement, so too is the Martian atmosphere affected.

“Stronger surface heating tends to produce stronger convection and convective vortices, which consist of fast winds whipping around low pressure cores,” writes atmospheric scientist Claire Newman of Aeolis Research on the Mars Exploration blog.

“If those vortices are strong enough, they can raise dust from the surface and become visible as ‘dust devils’ that we can image with our cameras.”


Dust devils are pretty well understood, and they come about the same way on both Earth and Mars. They form best in relatively flat, dry terrain, when the air at the surface level is warmer than the air above it.

This hot surface air rises through the cooler, denser air, creating an updraft. This causes the cooler air to sink. If a horizontal wind then blows through this vertical circulation, a dust devil whips into action.

They’re extremely common on Mars, but we only know this because, as they move across the ground, they sweep up the dust in their path, leaving tracks behind them. Actually seeing them in action on the Red Planet is quite rare, since our observational capabilities are limited, and dust devils themselves are relatively short-lived.

The dust devil above, seen in the top centre of the image, was captured by Curiosity’s Navcam on Sol 2847, and covers a span of about 5 minutes, Newman says. Even though it seems ghostly, the fact that we can see it means it was pretty powerful.

“We often have to process these images, by enhancing what’s changed between them, before dust devils clearly show up,” she writes. “But this dust devil was so impressive that – if you look closely! – you can just see it moving to the right, at the border between the darker and lighter slopes, even in the raw images.”

Studying these movies can reveal a lot about dust devils on Mars – where they form, for instance, how they evolve, how long they last, the type of dust they pick up, and how they vary from location to location.

They can also reveal wind speed and duration, which, in combination with meteorological readings, can help scientists learn more about Martian weather, and how dust devils fit into it.

Curiosity is the only operational rover on Mars at the moment (InSight is a stationary lander), so whatever surface information can be gleaned on Martial dust devils is very limited. Mars also has operational orbiters, though, which cover a lot more ground.

These have caught the occasional dust devil in action from space, as well as the many, many tracks they have left behind after they fade away.


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These Orbs Look Like Candy, But They’re Actually Different Flavours of Phobos

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NASA’s Mars Odyssey probe has been orbiting the Red Planet for almost 19 years now, making it the longest continually active spacecraft in orbit around a planet other than Earth.


That incredible tour of duty means it’s witnessed lots of strange things we can’t easily see from our terrestrial vantage point, and this stunning, colourful composite of the Martian moon Phobos is a great example of the alien sights Mars Odyssey gets to glimpse up close.

These six rather delicious-looking circular shapes may resemble some kind of fruit-flavoured candy, but they’re actually different glimpses of Phobos – with the colour variations representing different temperatures, as detected by Mars Odyssey’s infrared camera, the Thermal Emission Imaging System (THEMIS).

010 phobos temperature 1Temperature variations on the Martian moon Phobos. (NASA/JPL-Caltech/ASU/NAU)

THEMIS – which shares Greek mythology ties with both Phobos and its lunar sibling, Deimos – here reveals Phobos at its coldest in blue, when the Martian moon was fully shadowed by the Red Planet during a lunar eclipse.

By contrast, the bright red centres (seen top-right and bottom-left), show the thermal signature of Phobos under full sunlight, where the lunar surface directly facing the Sun heats up to a maximum temperature of around 27 degrees Celsius (81 degrees Fahrenheit).

“[It’s] a kind of temperature bullseye – warmest in the middle and gradually cooler moving out,” Odyssey project scientist Jeffrey Plaut explained in 2019.


“Each Phobos observation is done from a slightly different angle or time of day, providing a new kind of data.”

Ongoing analysis of Phobos and its surface features stands to reveal whether the tiny moon (with a radius of only about 11 kilometres, or 7 miles) is an asteroid that got pulled into the gravitational lure of Mars, or perhaps a lost chunk of the planet itself – a fragment that got chipped off by a surface impact in the Red Planet’s mysterious past.

Lots of questions remain, and Mars Odyssey’s ever-watchful eyes could be our best hope of securing the answers. We don’t have forever, though: Phobos, perhaps aptly named after the god of fear, may have already booked in its date with destiny.


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For The First Time, We Can See Patterns of an Eerie Glow in The Martian Atmosphere

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When the Sun sets in a blaze of blue and night falls over the dusty plains of Mars, something weird and wonderful occurs. High up above the surface, the atmosphere begins to glow with an ultraviolet light, sometimes pulsing, as nitrogen and oxygen combine into nitric oxide.


This invisible glow, first revealed by the Mars Orbiter mission in 2005, has now been characterised in detail – and its surprising behaviour is revealing how the Martian atmosphere circulates and changes over the course of the year.

Thin and tenuous as it may be, the atmosphere of Mars is surprisingly complex. Wild winds drive monster storms that can engulf the entire planet. There are seasonal fluctuations in its composition, as well as fluctuations that don’t fit any known processes.

Nightglow, by comparison, isn’t quite as mysterious. In fact, the same phenomenon – nightglow driven by the combination of nitrogen and oxygen, albeit in near-infrared wavelengths – has been observed on Venus, too. 

What it can tell us, however, is how Mars’s atmosphere circulates and changes seasonally, in order to help better predict the Red Planet’s crazy weather.

“If we’re going to send people to Mars,” said atmospheric scientist Zachariah Milby of the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics, “we better understand what’s going on in the atmosphere.”


The glow occurs when currents high in the Martian atmosphere fall in altitude as temperatures plummet. This altitude is where nitrogen and oxygen atoms (which have been split from CO2, O2, and N2 by sunlight during the day) combine into nitric oxide, emitting small bursts of ultraviolet light; in aggregate, it’s detectable as a nightglow.

The new observations come from NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) orbiter, which has been studying Mars in great detail since 2014.


Five times a day, MAVEN took detailed images of Mars using its Imaging Ultraviolet Spectrograph; with these observations, scientists could track the movements of the ultraviolet glow for the first time.

To the team’s great surprise, the atmosphere pulses three times a night – but only during spring and autumn. During these times, the glow appears around the planet’s middle, growing stronger around the equinoxes.

At other times of the year, the glow is brightest over the polar region in which winter reigns, strongest around the solstice. There, it forms unexpected configurations – waves and spirals.

“The ultraviolet glow comes mostly from an altitude of about 70 kilometres (44 miles), with the brightest spot about 1,000 kilometres (621 miles) across, and is as bright in the ultraviolet as Earth’s northern lights,” Milby said.

“Unfortunately, the composition of Mars’ atmosphere means that these bright spots emit no light at visible wavelengths that would allow them to be seen by future Mars astronauts. Too bad: the bright patches would intensify overhead every night after sunset, and drift across the sky at 300 kilometres per hour (186 mph).”

And there was another surprise – a persistent bright spot at approximately 0 latitude and 0 longitude, that has yet to be explained. It could be due to the terrain below, or something else that has yet to be discovered.

glow compThe equatorial (left) and polar (right) glow. (LASP)

The pulsations in particular reveal a link to waves in the Martian atmosphere. These circle the planet, and their number and speed show that the waves in the middle atmosphere are linked to the daily pattern of solar heating, as well as the shape of the terrain below.

The pulsating spots show a link between the middle atmospheric layer and those above and below – and this relationship is yet another aspect to be explored in future research.


There are still a number of questions to be answered, but the research is a step in the right direction in understanding the complex behaviour of the atmosphere of Mars.

“The behaviour of the Martian atmosphere is every bit as complicated and insightful as that of Earth’s atmosphere,” said lead author and planetary scientist Nick Schneider of CU Boulder.

“We use supercomputers to predict weather on Earth so that you can plan for your vacation or growing crops. The same computer models can be spun up for Mars and all the other planets.”

The research has been published in the Journal of Geophysical Research – Space Physics.


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The Majestic Valleys of Mars May Not Have Been Carved by Rivers After All

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The question of whether ancient life could have existed on Mars centres on the water that once flowed there, but new research published Monday suggests that many of the Red Planet’s valleys were gouged by icy glaciers not rivers. 


The study in Nature Geoscience, which comes amid a flurry of new Mars missions trying to discover if the now-barren planet ever hosted life, casts doubt on a dominant theory that the planet once had a warm, wet climate with abundant liquid water that sculpted the landscape. 

Researchers from Canada and the United States examined more than 10,000 Martian valleys and compared them to channels on Earth that were carved under glaciers.

“For the last 40 years, since Mars’s valleys were first discovered, the assumption was that rivers once flowed on Mars, eroding and originating all of these valleys,” said lead author Anna Grau Galofre in a statement released by the University of British Columbia.

But these formations come in a huge variety “suggesting that many processes were at play to carve them,” she added. 

Researchers found similarities between some Martian valleys and the subglacial channels of Devon Island, in the Canadian Arctic, which has been nicknamed “Mars on Earth” for its barren, freezing conditions and hosted NASA space training missions.

Mars and Antartic superimposed cover 3(Cal-Tech CTX mosaic and MAXAR/Esri)

Above: Collage showing Mars’s Maumee valleys (top half) superimposed with channels on Devon Island in Nunavut (bottom half). The shape of the channels, as well as the overall network, appears almost identical.

The study authors said their findings suggest that some Martian valleys could have been formed some 3.8 billion years ago by meltwater beneath ice sheets, which they said would align with climate modelling predicting that the planet would have been much cooler in its ancient past. 


“The findings demonstrate that only a fraction of valley networks match patterns typical of surface water erosion, which is in marked contrast to the conventional view,” said co-author Mark Jellinek

Nature Geoscience noted that understanding climate conditions “in the first billion years of Mars’ history is important in determining whether the planet was ever habitable”.

The study authors said that icy temperatures could in fact have better supported ancient life. 

“A sheet of ice would lend more protection and stability of underlying water, as well as providing shelter from solar radiation in the absence of a magnetic field – something Mars once had, but which disappeared billions of years ago,” the University of British Columbia statement said.

The research comes after NASA launched its latest Mars rover, Perseverance, to look for signs of ancient microbial life on the Red Planet.

If all goes to plan, Perseverance will reach Mars on 18 February 2021 and collect rock samples that could provide invaluable clues about whether there was ever past life on Mars.

However, the retrieval and analysis is not expected before the 2030s.

China has also launched its first Mars rover, which should arrive by May 2021.

© Agence France-Presse


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That Weird, Long Cloud on Mars Has Made a Dramatic Return

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Every good story deserves a sequel – and the strange white cloud spotted above an extinct Martian volcano back in 2018 just got one, because the stunning fog trail has made another appearance.


In fact, this is the latest instalment in a long-running series, and this time scientists were looking out expectantly for the event.

It’s thought that the white plume is formed from dense air near the planet’s surface getting forced uphill, where the temperature drops and the moisture condenses around dust particles.

It happens on Earth too: it’s called orographic lift.

So this doesn’t mean the long-dead Arsia Mons volcano is suddenly bursting back into life. But even though the cloud isn’t associated with volcanic activity, it’s still a stunning sight to behold.

“We have been investigating this intriguing phenomenon and were expecting to see such a cloud form around now,” says physicist Jorge Hernandez-Bernal, from the University of the Basque Country in Spain.

“This elongated cloud forms every Martian year during this season around the southern solstice, and repeats for 80 days or even more, following a rapid daily cycle. However, we don’t know yet if the clouds are always quite this impressive.”

Hernandez-Bernal is part of a team using the Visual Monitoring Camera (VMC) on the Mars Express probe to keep an eye on the Red Planet. The spacecraft has been in orbit for the past 16 years, watching the changing seasons and days.


A Martian day lasts a little over 24 hours, while a year lasts about 687 days – hence this being the cloud’s first appearance since 2018.

The cloud now has a name – it’s being termed the Arsia Mons Elongated Cloud, or AMEC.

Based on observations so far, it can stretch out to about 1,800 kilometres (1,118 miles), which on Earth would get it almost half way across the US.

And the VMC is the perfect instrument to capture it with – the photos above were taken on 17 July and 19 July. While most spacecraft view Mars in the afternoon due to their orbits, Mars Express is also watching in the early mornings.

That’s when this intriguing phenomenon appears, for about three hours at a time before disappearing. It also occurs during the southern solstice when the Sun is in the southernmost position in the Martian skies.



“The extent of this huge cloud can’t be seen if your camera only has a narrow field of view, or if you’re only observing in the afternoon,” says planetary scientist Eleni Ravanis, working on the Mars Express mission at the European Space Agency.


“Luckily for Mars Express, the highly elliptical orbit of the spacecraft, coupled with the wide field of view of the VMC instrument, lets us take pictures covering a wide area of the planet in the early morning. That means we can catch it!”

Scientists are continuing to try and understand the AMEC and it’s behaviour, but they’ve got a great vantage point.

You can see some of the stunning imagery that Mars Express has captured so far on Flickr.


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Scientists Detect Giant ‘Megaripple’ Structures Moving Across Mars

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For the first time, scientists have observed that ‘megaripples’ on Mars – huge sand waves seen on the Martian surface – are moving structures, and not ancient relics stuck in place since the Red Planet’s distant past.


Megaripples, which also occur in deserts on Earth, are generally larger than smaller sand ripples, and are composed of chunkier, coarser sand grains that sit at the top of their crests, resting on finer grains buried at the bottom.

The heftiness of the crest grains – combined with the very thin and faint winds of Mars’ light atmosphere today – had scientists thinking these sediment structures must be static and immovable formations. Not so, new research shows.

A study led by planetary scientist Simone Silvestro from the INAF Capodimonte Astronomical Observatory in Italy reveals Martian megaripples are a flowing phenomenon after all – although you have to watch very, very closely to catch them in the act.

By comparing images taken by the HiRISE camera (High Resolution Imaging Experiment) on NASA’s MARS Reconnaissance Orbiter over the space of several years, Silvestro’s team discovered the Martin megaripples are definitely in motion, just a very slow motion.

Between 2007 and 2016, megaripples at two Martian sites – Nili Fossae and McLaughlin crater – shifted at average speeds as low as 12 centimetres (4.7 inches) a year, with a top recorded speed of 19 centimetres (7.5 inches) per year.


At such slow rates of displacement, it’s perhaps no wonder these shifting sands were thought to be static – and previous comparisons examining the formations over shorter timeframes of only two to three Martian years had failed to detect the subtle migration. Now, thankfully, we have more probe data to draw upon, affording a closer look at what’s happening.

“We had the opportunity to see these megaripples moving because now we have more than 10 years of observations,” Silvestro explained to Inside Science.

It’s not just our probe imagery that’s expanded, however. So too has our understanding of what’s possible in the Martian atmosphere, as before this, researchers didn’t think Mars’ winds would be powerful enough within the thin atmosphere to move the megaripples – which are so large that they were spaced up to 35 metres (115 ft) apart in the areas studied here (although the average is about 5 metres, or 16 ft).

It seems the Martian wind can move the megaripples, provided it has some help. The researchers suggest the proximity of larger sand dunes located in the Nili Fossae and McLaughlin crater areas studied could be helping to shift the megaripples, with the finer-grained dunes providing a high volume of sand flux that may help displace the coarse grains sitting atop the megaripple crests.

Without such a level of “impact-driven creep” from neighbouring, saltating dunes, other Martian megaripples might not be able to move so much, nor as quickly as the speedy bunch glimpsed here.

While these megaripples may be slow, though, the fact that we can see them moving at all doesn’t only represent a significant increase in our knowledge of atmospheric conditions on Mars – it’s also just some very impressive science at work.

As planetary scientist Ralph Lorenz from Johns Hopkins University, who was not involved in the research, told Science: “We can now measure processes on the surface of another planet that are just a couple times faster than our hair grows.”

The findings are reported in the Journal of Geophysical Research: Planets.


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Humans Are About to Return a Rock to The Surface of Mars After 600,000 Years

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Humans are about to make history by sending a little piece of a Martian rock back to the surface of Mars for the first time ever.

The meteorite fragment Sayh al Uhaymir 008 (or SaU 008) will hitch a ride on the 2020 NASA Perseverance rover mission on Thursday – some 600,000 years after it left the Red Planet, and around 1,000 years after arriving on Earth.


Perseverance is going to use SaU 008 to calibrate its sensitive scanners and instruments once it lands, treating it as a reference point for the other rocks and materials that it’s going to come across in its journey across the Martian surface.

There’s still plenty that we don’t know about the geological make-up of Mars, and a rock fragment that we know originates from the planet – and that has already been extensively analysed – is going to be a helpful comparison point.

“This little rock’s got quite a life story,” Caroline Smith, the Head of Earth Sciences Collections and Principal Curator of Meteorites at the Natural History Museum in the UK, told the BBC.

“It formed about 450 million years ago, got blasted off Mars by an asteroid or comet roughly 600,000-700,000 years ago, and then landed on Earth; we don’t know precisely when but perhaps 1,000 years ago. And now it’s going back to Mars.”

mars rock 1 1024A slice of SaU 008. (NASA/JPL-Caltech)

The meteorite that SaU 008 comes from was found in Oman in 1999, and the SaU 008 fragment has been part of the Natural History Museum collection since 2000.

The tiny bubbles of gas trapped inside the rock are an exact match to the atmospheric conditions of Mars, which is how we know its origin.


A small slice of SaU 008 is going to be mounted onto the SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals) spectrometer, carried by Perseverance, which will use a laser to analyse the chemical and organic composition of Martian rocks.

Having a piece of original Mars meteorite on hand should make this study more accurate and reliable, and SHERLOC is taking along nine other different materials to test them in the atmosphere of the Red Planet – including a material that could be used in future spacesuits.

“The SHERLOC instrument is a valuable opportunity to prepare for human spaceflight as well as to perform fundamental scientific investigations of the Martian surface,” says SHERLOC co-investigator and curator of extraterrestrial materials Marc Fries, from the Johnson Space Center.

“It gives us a convenient way to test material that will keep future astronauts safe when they get to Mars.”

mars rock 2An artist’s concept of the Mars 2020 Perseverance rover. (NASA/JPL-Caltech)

Of course, there are other ways NASA could calibrate those instruments. But, as a paper presented at the 50th Lunar and Planetary Science Conference last year explained, the homecoming of part of SaU 008 also offers “unique education and public outreach purposes”.

Both NASA and SpaceX have a history of using unique and headline-grabbing items to help them in their missions – whether it’s a sparkly purple dinosaur used as a zero-gravity indicator, or a Tesla roadster as a test payload.


So, sending a Martian rock back to its home planet may be somewhat of a publicity stunt, but it’s a pretty cool one, with a useful purpose.

While a meteorite chunk has previously been blasted back into the orbit of Mars, this is going to be the first time a fragment like this will have been returned to the actual surface. It’ll be used around Perseverance’s landing site, the Jezero crater.

The 49-kilometre (30-mile) bowl may have once held a lake, and one of the jobs that Perseverance has is to look for any lingering traces of life. Any samples of interest are going to be packaged up and left for future missions to recover.

Material with signs of Martian life could eventually arrive back in 10-15 years, and if Perseverance does find something of note, then the homecoming of the small fragment of SaU 008 will be partially responsible.

“The piece of rock we are sending was specifically chosen because it is the right material in terms of chemistry, but also it is a very tough rock,” Smith told the Guardian. “Some of the Martian meteorites we have are very fragile. This meteorite is as tough as old boots.”

The Perseverance mission, with a bit of SaU 008 on board, is scheduled to launch on 30 July. You can watch the whole thing live below.


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The UAE Is About to Launch The Arab World’s First-Ever Mission to Mars

in Science News by

The United Arab Emirates is about to launch its first mission to Mars. It will be the Arab world’s first flight to another planet.

The SUV-sized spacecraft, called the Hope probe, will spend seven months travelling to Mars. Once it arrives, Hope will study the red planet’s atmosphere by monitoring how it interacts with solar wind and tracking its loss of hydrogen and oxygen.


Its goal will be to chart a global map of the planet’s climate across an entire Martian year.

That would be humanity’s first such picture of Mars’s atmosphere.

“We’ll be able to cover all of Mars, through all times of day, through an entire Martian year,” Sarah Al Amiri, science lead for the mission and the UAE’s minister for advanced sciences, told Nature.

The UAE's Hope orbiter. (United Arab Emirates Hope Mars Mission)The UAE’s Hope orbiter. (United Arab Emirates Hope Mars Mission)

Because of its large, oval-shaped orbit, Hope should be able to capture most of the planet in each of its 55-hour orbits.

“The Emiratis were very keen to make this not just a technology demonstrator, but make it contribute to the scientific understanding of Mars,” Richard Zurek, chief scientist for the Mars Program Office at NASA’s Jet Propulsion Laboratory, told Nature.

The probe is set to launch from the Tenaghashima Space Centre in Japan at 4:51 pm Eastern Time on Tuesday. It will be early Wednesday morning in Japan.

Hope is one of three missions poised to launch for Mars in the final weeks of July. NASA plans to launch its next Mars rover, called Perseverance, on July 30. China is also gearing up to launch a rover, along with its own Mars-orbiting spacecraft, before the month is over.


The launches are scheduled so close together because they must catch Mars as it passes close to Earth in the planets’ orbital paths. If the agencies involved miss this chance, they won’t have another opportunity to launch until 2022.

If all goes well, the Hope probe will reach Mars by February 2021 and study the planet from above for two years.

Watch the UAE’s livestream of the launch below.

The Japanese launch provider, Mitsubishi Heavy Industries, will also broadcast the launch live:

This article was originally published by Business Insider.

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