Tag Archives: life on mars

Microbial earthly life could survive on Mars, at least for a time

In a new study, NASA and German Aerospace Center scientists found that Earth microbes can withstand Martian conditions, which means we could use them there, but they could also pose risks for astronauts.

Sturdy microbes

You’re never really alone. You’ve got a gazillion tiny critters on yourself at any given moment. Most are harmless. Some can be useful — and of course, some can be harmful.

Try as we might (and space agencies do try), there’s no realistic way to eliminate all microbes from a crewed mission. Even with all the available decontamination procedures, you can’t really kick all off them from everywhere. If (or perhaps when?) we fly astronauts to Mars, the mission will bring some microbes along, like it or not.

Some have suspected that this wouldn’t matter at all, because the microbes just wouldn’t be able to survive on Mars. But a new study says otherwise.

“We successfully tested a new way of exposing bacteria and fungi to Mars-like conditions by using a scientific balloon to fly our experimental equipment up to Earth’s stratosphere,” reports Marta Filipa Cortesão, joint first author of this study from the German Aerospace Center, Cologne, Germany. “Some microbes, in particular spores from the black mold fungus, were able to survive the trip, even when exposed to very high UV radiation.”

The endurance of microbes and their ability to withstand Martian conditions is important for any human Mars mission. For one, they could be dangerous for astronauts, or confuse them — finding life forms on Mars would be exciting, but not if you’ve brought them yourself from Earth. But microbes could also help a potential research station or colony, helping with things like making water or fuel.

“With crewed long-term missions to Mars, we need to know how human-associated microorganisms would survive on the Red Planet, as some may pose a health risk to astronauts,” says joint first author Katharina Siems, also based at the German Aerospace Center. “In addition, some microbes could be invaluable for space exploration. They could help us produce food and material supplies independently from Earth, which will be crucial when far away from home.”

Mars, on Earth

Quartz disc with dried Aspergillus niger spores, before being placed in the aluminum sample carriers that went on the Trex-box. Image credits: German Aerospace Center (DLR).

To find out whether microbes could survive on Mars, researchers sent them into the stratosphere on a balloon mission. There, the microbes were kept at Martian pressure and in a specially-prepared artificial Martian-mimicking atmosphere.

“The box carried two sample layers, with the bottom layer shielded from radiation. This allowed us to separate the effects of radiation from the other tested conditions: desiccation, atmosphere, and temperature fluctuation during the flight. The top layer samples were exposed to more than a thousand times more UV radiation than levels that can cause sunburn on our skin.”

Not all the microorganisms made it back, but some did, like the black mold Aspergillus niger, for instance. Aspergillus niger is less likely to cause human disease than some other Aspergillus species. However, many useful enzymes are produced using the industrial fermentation of the mold.

Next, researchers have to build a larger catalog of what microbes might survive the trip to Mars and use the information to prepare accordingly for future Mars missions.

“Microorganisms are closely-connected to us; our body, our food, our environment, so it is impossible to rule them out of space travel. Using good analogies for the Martian environment, such as the MARSBOx balloon mission to the stratosphere, is a really important way to help us explore all the implications of space travel on microbial life and how we can drive this knowledge towards amazing space discoveries.”

The study has been published in Frontiers.

14 Mars facts we’ve only learned in recent years

We’ve learned a great deal about Mars in recent years. It’s not the alien-populated planet it was once believed to be, but it’s definitely not the dull, meaningless planet some portray it as. Mars is, in many ways, very much like Earth. Just like Earth, Mars hosted vast amounts of water (something we’ve also learned recently) — but unlike Earth, it no longer has a rich atmosphere, its water is only preserved in pockets, and it is (at least for the most part) lifeless.

However, it seems like the more we learn about Mars, the more questions arise. For every tantalizing answer, three more burning questions arise. Thankfully, more missions are en-route to Mars, including China’s Tianwen-1, the United Arab Emirates’ Hope Probe, and NASA’s Perseverance rover, which could help solve some of these mysteries. For now, here are some Mars facts we’ve recently learned.

Mars is a ‘wobbly’ planet just like Earth, but we’re not really sure why

Image credits: NASA.

As the Earth spins during its day, it also wobbles and bobbles ever so slightly around its own axis. Astronomers aren’t really sure why this is happening, but they recently learned that Mars also does it.

It’s called the Chandler Wobble: when a rotating body’s mass isn’t distributed evenly, which causes a wobble. In Earth’s case, it’s mostly caused by its shape, which isn’t perfectly round. In the case of the much rounder Mars, we’re not really sure why it happens, but it could be because of atmospheric motions.

The Martian landscape may have been shaped by megafloods

Mars is, for the most part, a barren and inhospitable place. But go back a couple billion years, and the planet would have been much different. Researchers are now pretty sure that it was once home to oceans and river systems, but according to a new study, it was also subjected to powerful megafloods.

According to the new study, the megafloods would have been triggered by an asteroid impact 4 billion years ago. Although the water is now gone long, evidence of the ripples can still be seen in the shape of the Martian sediments. “Early Mars was an extremely active planet from a geological point of view,” a co-author of the study said in a press release. “The planet had the conditions needed to support the presence of liquid water on the surface”.

Mars still has multiple bodies of liquid water

Speaking of water on Mars, September 2020 was a groundbreaking moment, as researchers published data showing that Mars still has salty lakes sealed under its icy polar regions. These subglacial lakes are exciting for two reasons: first, where there’s water there could also be life, and subglacial lakes would be an ideal place to look for life on Mars; and second, this water could also be useful in establishing a human base or settlement on Mars.

When talking about water on Mars, we usually talk in the past tense. Mars had a rich water system, but now it’s gone — the fact that it still has large bodies of liquid water came as quite a shock and made Mars much more interesting than before.

It has auroras

The Martian aurora takes place at night and is generated by the interaction of sunlight with oxygen atoms and molecules in the air. The emission is very difficult to see, even from Earth, which is relatively nearby. The Mars aurora was imaged by European Space Agency’s Trace Gas Orbiter (TGO), which explored the Martian atmospheric environment before delivering the Schiaparelli lander, which crashed on the surface due to a premature release of the parachute.

But here’s the thing: Mars gets auroras almost every day, it’s just that we can’t see them. Unlike their Earthly counterparts, however, you’d need some ultraviolet goggles to see the Martian aurora.

MAVEN images of the Martian atmosphere under normal conditions (left) and with an aurora (middle and right). Credit: Embry-Riddle Aeronautical University/LASP, CU Boulder.

Mars may have had planetary rings (and may get another one)

‘Mars’ and ‘planetary rings’ don’t really seem to get together in the same sentence. After all, planetary rings seem reserved for gas giants like Jupiter or Saturn. But astronomers have recently suggested that Mars may have also had planetary rings.

Mars has two tiny moons, Phobos and Deimos. These moons rotate almost in the same plane as the Red Planet’s equator, which means the moons likely formed at the same time as Mars. However, one of the moons (Deimos) is tilted by two degrees, something which no one really bothered with until recently. Now, a team of astronomers is suggesting that this tilt can only be explained by a grandparent moon which broke down, producing planetary rings in the process.

It had a system of giant rivers that lasted billions of years

Valles Marineris, the largest canyon in the solar system, would put the Grand Canyon to shame (it’s over 10 times larger). Image credits: NASA.

When researchers say Mars had water, it’s not a joke. Analyzing new images of the sedimentary structure of Mars, a team of researchers concluded that in order to produce what can be observed now, the Martian rivers must have lasted for a very long time — up to billions of years.

The sedimentary rocks record layers of history, and the researchers were able to determine that the channels of these ancient rivers were around 9 or 10 feet deep. Mars had “rivers that continuously shifted their gullies, creating sandbanks, similar to the Rhine or the rivers that you can find in Northern Italy,” the researchers said in their study.

It may have been habitable as early as 4.4 billion years ago

We don’t know if Mars was ever truly habitable, but there’s a good chance it was — and for a long time. A 2019 study suggests that Mars may have exhibited conditions fit for harboring life as early as 4.48 billion years ago, predating the earliest evidence of life on Earth by around 500 million years.

There’s a great deal of speculation regarding the potential for life on Mars, but if the planet ever was habitable, and if it had conditions similar to Earth, then life may have well emerged on the Red Planet before Earth. Heck, it could have even migrated from Mars to Earth on meteorites — though again, at this point, this is just speculation.

Photomicrograph by Opportunity showing a gray hematite concretion, nicknamed “blueberries”, indicative of the past existence of liquid water. Image credits: NASA.

Some of its clouds are made of ground-up meteors

The first strange thing about the Martian clouds is that they exist at all. Down here on Earth, clouds form around tiny particles like grains of dust or salt which act as anchors for water vapor to condense on. But to our knowledge, this mechanism doesn’t exist on Mars.

Around two to three tons of space debris rain down on Mars, on average, every single day, and a new study suggests that these particles form the seed of Martian clouds. The findings are supported by previous research showing that a similar mechanism may help seed clouds near Earth’s poles (where the magnetic shield is weakest).

It has earthquakes — I mean ‘marsquakes’

Unlike Earth, Mars doesn’t really have an active tectonics, which means that its seismic activity is way less intense than that of Earth’s. However, after months of waiting, the Seismic Experiment for Interior Structure (SEIS) on board the InSight Mars lander detected its first ‘marsquake’.

Earthquakes (and marsquakes) are useful for researchers because they can offer information about the subsurface. By analyzing the seismic waves, researchers can infer the structure of the entire planet — that’s how we know what the Earth’s inside looks like, and that’s how we could also understand what Mars is like on the inside.

Mars also has methane

Methane is a key molecule for life. The presence of methane could enhance habitability and may even be a signature of life, but it was only confirmed independently on Mars in 2019. Using numerical modeling and geological analysis, a team of researchers at the National Institute of Astrophysics in Rome, Italy, propose not only that methane on Mars exists, but also suggest where it could be located.

Methane is a chemical compound closely associated with microbial life, but it isn’t necessarily biological in nature. There’s a very good chance that the methane is generated geologically, and this is what this new paper also suggests. However, since researchers pinpointed a promising location for future investigations into the origin of methane on Mars, we have a starting point for future missions to look into the origin of this methane.

Mars may yet hold life in salty subsurface waters

As you may have picked up already, a lot of what we’ve learned about Mars recently has to do with the water — but there’s a big reason why we focus so much on this. Water determines potential habitability, and where water exists, life (as we know it) can also exist. If water exists on Mars, this doesn’t automatically mean that life also exists, but it means that life could exist on Mars, and that’s exciting in its own right.

This is different from the study that found subglacial lakes. A 2018 study found that some of the subsurface water on Mars could be rich enough in oxygen to support aerobic life. “That’s the thing of habitability; we never thought that environment could have that much oxygen,” said one of the study authors.

Martian soil is suitable for making bricks

Made from compacted Martian soil, without the need for additional ingredients or baking, this simple brick could one day house our first colonists on the red planet. Image credits: Jacobs School of Engineering / UC San Diego.

If you want to bake an apple pie from scratch, you may have to invent the universe first — but if you want to make bricks from Martian soil, all you need to do is press really hard on it. A team of engineers at the University of California San Diego worked with a Mars soil simulant and managed to develop durable bricks just by pressing them really hard.

All it takes is the for equivalent to a 10 pound hammer dropped from a height of one meters, they say. Surprisingly enough, with this method, you don’t need ovens or any other ingredients. The method may be compatible with additive manufacturing, meaning astronauts wanting to build a structure would simply have to lay down a layer of dirt, compact it, lay another layer and so on until they’re done.

The Martian atmosphere was stripped by solar wind

Another important question to answer is how Mars got to how it is today. How could a planet with lush river valleys, floods, and active geology become so barren? The key lies in the disappearance of its atmosphere, and according to a recent study, its atmosphere was stripped away by solar wind.

Unlike Earth, Mars lacks a global magnetic field to deflect the stream of charged particles continuously blowing off the Sun. Instead, the solar wind crashes into Mars’ upper atmosphere and can accelerate ions into space, and the atmosphere, once rich enough to support liquid water, is now all but gone.

In its early days, Mars may have been covered by ice

A large number of valley networks scar the Martian surface, but they may have been caused by water melting beneath glacial ice, not free-flowing rivers.

Funnily enough, this type of environment would have been even better for possible ancient life forms. A sheet of ice lends protection and stability, as well as shelter from solar radiation in the absence of a magnetic field (something which Mars once had, but has been gone for billions of years).

These are just some of the many things we’ve learned about Mars recently, thanks to diligent observations and several landmark Mars missions, both in orbit and on the surface of the planet. As the missions continue to unfold and expand, so too will our understanding of the Red Planet.

Undoubtedly, we missed some bits here. Is there anything you’d like to see added to this list? Mention it in the comment section.

The melting of ice beneath the surface of Mars could have made its deep regions the most habitable.

Life could have prospered beneath the surface of Mars

Even after liquid water was stripped from its surface, new research suggests that freshwater miles beneath the surface could have sustained life. (Steve Lee, Univ. Colorado/Jim Bell, Cornell Univ./Mike Wolff, SSI/NASA)

Life-sustaining water could have existed miles beneath the surface of Mars thanks to the melting of thick ice sheets by geothermal heat, new research has found. The discovery, made by a team led by Rutgers University scientists, suggests that 4 billion years ago the most likely place for life to prosper on the Red Planet was beneath its surface.

The study, published in the latest edition of the journal Science Advances, could solve a problem that also has implications for the existence of liquid water–and thus the early development of life–on our planet too. Thus far, researchers looking into the existence of liquid water early in both Earth and Mars’histories have been puzzled by the fact that the Sun would have been up to 70% less intense in its stellar-youth.

A vertically exaggerated and false-colour perspective of a large, water-carved channel on Mars called Dao Vallis. Whether channels like these on Mars were carved by surface water or groundwater is highly debated. The channel is ~40 km wide, ~2.5 km deep, and more than 500 km in length. (ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO. 3D rendered and coloured by Lujendra Ojha.)
A vertically exaggerated and false-colour perspective of a large, water-carved channel on Mars called Dao Vallis. Whether channels like these on Mars were carved by surface water or groundwater is highly debated. The channel is ~40 km wide, ~2.5 km deep, and more than 500 km in length. (ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO. 3D rendered and coloured by Lujendra Ojha.)

This lack of intensity coupled with findings of liquid water at this stage in the solar system’s history is referred to as ‘the faint-sun paradox,’ and should mean that Mars conditions were cold and arid in its deep history. This conclusion was contradicted by geological evidence of liquid water on the young planet. The problem could now be solved, for Mars at least, by geothermal activity.

“Even if greenhouse gases like carbon dioxide and water vapour are pumped into the early Martian atmosphere in computer simulations, climate models still struggle to support a long-term warm and wet Mars,” explains lead author Lujendra Ojha, assistant professor in the Department of Earth and Planetary Sciences in the School of Arts and Sciences at Rutgers University, New Brunswick. “We propose that the faint young sun paradox may be reconciled, at least partly, if Mars had high geothermal heat in its past.”

Lujendra Ojha, Jacob Buffo, Suniti Karunatillake, Matthew Siegler. [2020]
Lujendra Ojha, Jacob Buffo, Suniti Karunatillake, Matthew Siegler. [2020]

The status of Mars climate billions of years ago and if freshwater could have existed its this point early in its history has been a source of heated debate in the scientific community for decades. The discussion has been further complicated by the question of whether water would have existed on the planet’s surface or deep underground? Climate models produced for Mars thus far have suggested average surface temperatures below the melting point of water at this point in its history.

Ojha and his team investigated this seeming contradiction in our understanding of Mars by modelling the average thickness of ice deposits in the Red Planet’s southern highlands. They also examined data collected by NASA’s InSight lander, which has been measuring the ‘vitals’ of the Red Planet since 2018.

Discovering that the thickness of these ice deposits did not exceed an average thickness of 2 kilometres, the team complemented this finding with estimates of both the planet’s average annual surface temperature and the flow of heat from its interior to its surface. The aim of this was to discover if the surface heat flow would have been strong enough to melt Mars’ ice sheets.

Indeed, the study seems to show that the flow of heat from both the crust and mantle of Mars would have been intense enough to begin melting at the base of its ice sheets.

Did Life on Mars prosper Beneath its Surface?

Water still exists on Mars in the forma of Ice as seen in the Korolev crater. (ESA)
Water still exists on Mars in the forma of Ice as seen in the Korolev crater. (ESA)

The wider implication of this revelation is that whatever the climate of Mars was like billions of years in its history if life once existed on the Red Planet, its subsurface would have been its most habitable region. Thus, life could have prospered, say the team, miles beneath the surface of our neighbour, sustained by the flow of freshwater.

Significantly, this supply of water would have existed even as Mars lost its magnetic field and its atmosphere was stripped away by harsh solar winds and blistering radiation. The process which ultimately deprived Mars of its surface liquid water. This means that life could have survived on the planet, hidden miles underground for much longer than the surface remained habitable.

“At such depths, life could have been sustained by hydrothermal activity and rock-water reactions,” says Ojha. “So, the subsurface may represent the longest-lived habitable environment on Mars.”

Source: Lujendra Ojha, Jacob Buffo, Suniti Karunatillake, Matthew Siegle. ‘Groundwater production from geothermal heating on early Mars and implication for early martian habitability,’ Science Advances,[2020] https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.abb1669

Creatures beneath the seafloor give hope for life on Mars

Finding microbial life thriving in some of the most extreme environments on Earth is usually a reason for celebration for researchers, as it can guide their search for life on other planets — especially on Mars, their most recent focus of attention.

Credit University of Tokyo

Newly discovered single-celled creatures living deep beneath the seafloor have given clues about where life on Mars could be found. The bacteria were discovered by the University of Tokyo geomicrobiologist Yohey Suzuki, after a decade examining ancient rocks pulled from the depth of the sea.

Suzuki hypothesized that the cracks in these rocks are home to a community of bacteria as dense as that of the human gut, about 10 billion bacterial cells per cubic centimeter. In contrast, the average density of bacteria living in mud sediment on the seafloor is estimated to be 100 cells per cubic centimeter. The hypothesis turned out to be true.

“I am now almost over-expecting that I can find life on Mars. If not, it must be that life relies on some other process that Mars does not have, like plate tectonics,” Suzuki said in a statement. “I thought it was a dream, seeing such rich microbial life in rocks.”

Undersea volcanoes spew out lava at approximately 1,200 degrees Celsius (2,200 degrees Fahrenheit), which eventually cracks as it cools down and becomes rock. The cracks are narrow and over millions of years, those cracks fill up with clay minerals. Somehow, bacteria find their way into those cracks and multiply.

“These cracks are a very friendly place for life. Clay minerals are like a magic material on Earth; if you can find clay minerals, you can almost always find microbes living in them,” explained Suzuki. “Honestly, it was a very unexpected discovery. I was very lucky because I almost gave up.”

Suzuki and his colleagues discovered the bacteria in rock samples that he helped collect in late 2010 during the Integrated Ocean Drilling Program (IODP), which took researchers to the tropical island of Tahiti in the Pacific Ocean. They used a metal tube to reach the ocean floor and obtain core samples.

Depending on the location, the rock samples were estimated to be 13.5 million, 33.5 million, and 104 million years old. The collection sites were not near any hydrothermal vents or sub-seafloor water channels, so researchers are confident the bacteria arrived in the cracks independently rather than being forced in by a current.

Whole-genome DNA analysis identified the different species of bacteria that lived in the cracks. Samples from different locations had similar, but not identical, species of bacteria. Rocks at different locations have different ages, which may affect what minerals have had time to accumulate therein and therefore what bacteria are most common.

Suzuki and his colleagues speculate that the clay mineral-filled cracks concentrate nutrients that the bacteria use as fuel. This might explain why the density of bacteria in the cracks is eight orders of magnitude greater than the density of bacteria living freely in mud sediment where seawater dilutes the nutrients.

“Minerals are like a fingerprint for what conditions were present when the clay formed. Neutral to slightly alkaline levels, low temperature, moderate salinity, iron-rich environment, basalt rock — all of these conditions are shared between the deep ocean and the surface of Mars,” said Suzuki.

The researchers are now collaborating with NASA’s Johnson Space Center to design a plan to examine rocks collected from the Martian surface by rovers. Ideas include keeping the samples locked in a titanium tube and using a CT (computed tomography) scanner, a type of 3D X-ray, to look for life inside clay mineral-filled cracks.

The study was published in the journal Communications Biology.

A scientist claims there are insects on Mars. He’s probably wrong

An entomologist says photos taken by the Curiosity rover depict bugs. His critics say he has pareidolia.

Image credits: NASA/JPL; William Romoser/Ohio University.

The claim

William Romoser, an entomologist and a professor at Ohio University, presented a research poster at a conference in St Louis and said he has evidence of current life on Mars. The said there are “insect-like” and “reptile-like” forms on the planet, which he claimed has a “surprising abundance of higher life forms.”

Romoser spent a few years studying photos from Mars he obtained online. He claimed to have found on them several examples of insect-like forms with a structure similar to bees as well as reptile-like forms including fossils and living organisms.

“There has been and still is life on Mars,” Romoser said. “There is apparent diversity among the Martian insect-like fauna which display many features similar to Terran insects that are interpreted as advanced groups – for example, the presence of wings, wing flexion, agile gliding/flight, and variously structured leg elements.”

The researcher said the photos show images of arthropod body segments as well as legs, antennae, and wings. He claimed to have carefully studied the photos and not to have removed or added content to them, having variated photographic parameters such as contrast and saturation.

“Once a clear image of a given form was identified and described, it was useful in facilitating recognition of other less clear, but none-the-less valid, images of the same basic form,” Romoser said. “An exoskeleton and jointed appendages are sufficient to establish identification as an arthropod.”

Image credits: NASA/JPL; William Romoser/Ohio University.

The proof

That’s it — you’re basically seeing it above. Romoser’s claims are based on the images and the images alone.

Great claims require great proof, and this really isn’t great proof — that’s putting it lightly.

The research was widely questioned in social media and the academic world. Amanda Kooser, CNET writer, said Romoser suffers from pareidolia, a human tendency to see recognizable shapes in random patterns – something commonly found among alien enthusiasts.

Romoser dedicated most of his academic life to studying insects, so he could be seeing insects where there are none. He also has a history of bold (and quite fringe) claims regarding Mars. He published two past reporters where he claimed to have found evidence of intelligent life forms on the red planet.

Even this is putting it lightly: Twitter had a field day with Romoser’s claims.

Romoser is an accomplished entomologist — but if he wants people to take these claims more seriously, substantially more evidence is required.

However, it should be said that he presented the claims at the Entomology conference — and conferences are exactly where preliminary results should be presented. It remains to be seen whether these Martian bugs will pass the test of serious scientific screening — but I wouldn’t bet on it.

If we don’t hurry, the life we find on Mars might be from Earth

“There is a ticking clock now,” Princeton astrobiologist Chris Chyba said at last week’s Breakthrough Discuss conference, conducted at Stanford University. The race isn’t to find life on Mars — it’s to find it in time before we contaminate the Red Planet with our Earthly microbial fauna.

Is there life on Mars? Even if there is, is it from Mars? Image credits: NASA / JPL.

We don’t know if there is life on Mars or not. The Red Planet seems like a good candidate, and we’ve found significant evidence that it might have held vast quantities of liquid water on its surface at once point in its geological past — a prerequisite for life as we know it. There’s also a good case to be made against this, with its lack of active tectonics and atmosphere. If Martian life exists, it’s bound to live beneath the surface where it’s shielded from the devastating radiation, and almost certainly microbial. Either way, it’s an exciting area of active research, but we might be on a clock.

With every mission we send to Mars, every lander, and especially with the planned manned missions to Mars, we risk contamination with microbial creatures from Earth. These alien microorganisms (technically, they’re Earth microorganisms, but to Mars, they’d be aliens) could overpower and destroy potentially existing native fauna.

For instance, Elon Musk’s highly anticipated mission to Mars aims to bring people to Mars within the decade, and Boeing CEO Dennis Muilenburg has announced similar plans. For the Martian life, the effects would be unforeseeable — hence Chyba’s remarks. But people weren’t necessarily fond of his idea. Longtime space entrepreneur Jeff Greason, who serves as chairman of the board for the Tau Zero Foundation, poked fun at Chyba:

“If all you want to do with the solar system is look at it, the rest of us would like to borrow it for a while. … There are things to do with these bodies other than science.”

Others have claimed that there’s no reason to believe Earth’s microbes would take over the Martian natives.

“You could terraform Mars, and the microbes on Mars would survive,” said Robert Zubrin, founder and president of the nonprofit Mars Society.

But Chyba makes a very valid point. If we don’t really know what could happen, isn’t it better to take extra precautions? He advocates a precautionary approach, what he calls the Smokey the Bear argument: “Until we know more, let’s be careful.”

To me, this sounds like a sound idea. There are many unknowns when it comes to Mars and its habitability, but we can take measures to limit the potential damage, for instance by ensuring that no microorganisms escape through astronauts’ space suits. If we send people to Mars, microbes are bound to come along for the ride, and the effects can truly be unforeseeable. We shouldn’t just concede that we’re gonna contaminate Mars no matter what.

Re-emerging life in Earth’s driest desert sparks hopes for life on Mars

For the first time, researchers have found evidence of life rebounding in the world’s driest desert: the Atacama; and if it can rebound there, it might be able to do the same thing on Mars.

Chile’s Atacama Desert is the driest non-polar desert on Earth — and a ready analog for Mars’ rugged, arid terrain. Image Credit: NASA/JPL-Caltech.

In South America’s Atacama Desert, it almost never rains. It’s the driest nonpolar place in the world, with an average rainfall of 15 mm (0.6 in) per year. In some areas, decades can pass without a single rain event.

Scientists have long wondered if the microbes they’ve been seeing around the desert are actually living there or are merely vestiges blown away by the wind. In a new study, Washington State University planetary scientist Dirk Schulze-Makuch and his colleagues found evidence that even this extremely arid environment can host life. They found that when things get tough, microorganisms can turn dormant for decades, then bounce back to life.

“It has always fascinated me to go to the places where people don’t think anything could possibly survive and discover that life has somehow found a way to make it work,” Schulze-Makuch said. “Jurassic Park references aside, our research tell us that if life can persist in Earth’s driest environment there is a good chance it could be hanging in there on Mars in a similar fashion.”

The finding was made possible through a spur of luck. When Schulze-Makuc and his team went to the Atacama in 2015, something incredible happened: it rained. After this extremely rare shower, researchers took soil samples, and found they were teeming life forms where almost none could be found before.

They identified several microbial communities reproducing in the samples, including indigenous species of microbial life that had adapted to the harsh environment. After they went back in 2016 and 2017, they found that the microorganisms were slowly turning dormant again as the humidity faded away.

“In the past researchers have found dying organisms near the surface and remnants of DNA but this is really the first time that anyone has been able to identify a persistent form of life living in the soil of the Atacama Desert,” Schulze-Makuch said. “We believe these microbial communities can lay dormant for hundreds or even thousands of years in conditions very similar to what you would find on a planet like Mars and then come back to life when it rains.”

They also found three different populations of viruses that were apparently linked to the microbial blooms — though viruses were not the central focus of this study, Schulze-Makuch told ZME Science.

Of course, while this does raise interesting perspectives for extraterrestrial life, the surface of Mars is much tougher than Atacama. Sure, Atacama is a hellish environment in its own right, but Mars is also lacking an atmosphere and is much more exposed to cosmic rays. It’s also much colder than Atacama, though it wasn’t always like this.

Modern research suggests that Mars (or at least some areas of it) were once lush environments, filled with small oceans and lakes where early lifeforms may have thrived. As the planet gradually became drier and cooler, these microorganisms may have developed evolved special adaptations to the changing environment, much like the Atacama creatures. But Mars also has an advantage — unlike the Atacama, it has pockets of frozen water beneath its surface.

“We know there is water frozen in the Martian soil and recent research strongly suggests nightly snowfalls and other increased moisture events near the surface,” he said. “If life ever evolved on Mars, our research suggests it could have found a subsurface niche beneath today’s severely hyper-arid surface.”

Of course, Earth’s substitutes for Martian environments can only go so far in replicating the conditions of the Red Planet, but the Atacama holds some promising signs. It’s unclear for how long these microorganisms can last, Schulze-Makuch told ZME Science. “They can at least survive a decade or so without rain, but probably much much longer,” he explained in an email.

Now, Schulze-Makuch says he and his team would like to look for lifeforms in the Don Juan Pond in Antarctica, a shallow lake, so salty it remains liquid even at temperatures way below freezing.

Unfortunately, it currently wouldn’t be possible to deploy all the technology on a Mars rover, but parts of it could certainly be included in future missions, Schulze-Makuch concludes.

The study has been published in the Proceedings of the National Academy of Sciences. http://dx.doi.org/10.1073/pnas.1714341115

Atmospheric methane on Mars changes with the seasons — and we don’t really know why

Methane, a substance which goes hand in hand with life on Earth, has also been found on Mars. At a meeting of the American Geophysical Union (AGU) in New Orleans, Louisiana, NASA scientists reported that atmospheric methane on Mars exhibits a surprising variation. Its causes are still unknown.

How the surface of Mars looks like. Image credits: NASA / JPL.

Red Methane

Many things on Earth, from wetlands to permafrost, and from plants to animals themselves, generate methane. Researchers have been closely monitoring this substance as it is the most potent greenhouse gas in our atmosphere, albeit much more short-lived than CO2, for instance. But researchers were surprised to see any methane at all on frigid, barren Mars. Even more surprising was the large variation of the gas.

“The thing that’s so shocking here is this large variation,” said Chris Webster, who leads the methane-sensing instrument on NASA’s Curiosity rover. “We’re left trying to imagine how we can create this seasonal variation,” says Webster, who is at the Jet Propulsion Laboratory in Pasadena, California.

Scientists analyzed data from the Curiosity Rover. Since it landed on the Red Planet, the rover sampled Martian air 30 times, reporting extremely small background levels of the gas: around 0.4 parts per billion (ppb), compared with Earth’s 1800 ppb. But even small quantities need to come from somewhere. To make things even more mysterious, methane levels have been cycling from 0.3 ppb and 0.7 ppb over just two Martian years.

Some seasonality is, of course, to be expected. However, the mechanisms we’re currently aware of don’t even get close to explaining a variation of this magnitude. It could be that whatever is generating the methane has a temperature variation, which could translate to seasonality, but this is mere speculation at this point.

Diving into the realm of speculation, there’s also another possibility — “one that no one talks about but is in the back of everyone’s mind” — biological activity, says Mike Mumma, a planetary scientist at Goddard Space Flight Center in Greenbelt, Maryland. “You’d expect life to be seasonal.”

Life on Mars

Most of the methane on Earth was generated by microbes. There’s a good chance that the same process is, or was, happening on Mars. If this is the case, we would be dealing with either contemporary or ancient microbes. But ancient microbes wouldn’t really explain the seasonal variation, so going on this train of thought, it would appear more likely that we’re dealing with active microbial life on Mars. Yet this isn’t the only possible explanation.

Methane observations on Earth, showing the seasonal variations and the difference between northern and southern hemispheres. There’s a much lower variation than what was observed on Mars. Image credits: National Oceanic & Atmospheric Administration.

Methane can also be generated through geological processes which have nothing to do with biology. Methane can be produced through hydrothermal reactions, especially ones involving olivine-rich rocks. It can also appear when carbon-containing meteoroids are bombarded by ultraviolet (UV) light, and dust falls down on the planet. This particular theory could also help explain the large variation.

Basically, the same chemical that produces methane from interplanetary dust at the surface level would be power-charged by UV light at high altitudes. As meteorite or comet dust particles fall down on the planet, they’re vaporized at tens of kilometers high in the air, producing significant quantities of methane. Since Curiosity’s reported variation can be somewhat correlated to meteor showers, Marc Fries, the cosmic dust curator at Johnson Space Center in Houston, Texas, believes this might explain the seasonality. But not everyone is convinced, and Fries himself concedes that meteor showers are highly variable and a causation is difficult to establish.

However, the good news is that Fries will have a chance to test his hypothesis: on 24 January, Mars will have a close encounter with comet C/2007 H2 Skiff — the comet is set to pass at less than a tenth of the Earth-moon distance. Even skeptics agree that this is a good opportunity to test the theory.

To make things even better, the European Space Agency’s ExoMars Trace Gas Orbiter will start observations on Mars, mapping methane distributions across the planet. But if neither of these tests confirms Fries’ theory, it’s back to the drawing board.

Curiosity rover finds that its landing crater on Mars could have been habitable for 700 million years

The Curiosity Rover is earning its keep, sending back more and more valuable information about the Red Planet.

A rendering of Gale Crater, with Mount Sharp at its center. The Curiosity rover is currently exploring this area, trying to find whether Mars could have supported life. Image credits: NASA.

When researchers and engineers decided to land Curiosity inside Gale Crater, they didn’t choose randomly. The crater, which contained a massive lake, was chosen because due to its structure, there’s a good chance of learning many of Mars’ geological secrets. While it was already established that Mars held water, the conditions of the water and the overall environment is still unclear. Now, this research shows that not only was the planet hosting a lot of water — it had lakes much like those on Earth.

Geochemist Joel Hurowitz from Stony Brook University led a large team that analyzed over 100 meters of rock layers in Gale Crater. To reconstruct the past environment, they measured the aluminum inside each layer, plotting it against minerals like sodium and calcium, which easily leach out of the rock. Basically, warm water is more chemically active than cold water. During warm conditions, water is better at dissolving and absorbing stuff (just like how sugar melts easier in hot water). In this case, if a rock has a lot of aluminum but not so much sodium or calcium, it indicates that it formed in a warmer environment.

Oxygen was another key component they looked at. There are sharp differences between deeper and more shallow water, in terms of oxygen content. By adding the oxygen content into the mix, researchers were able to show that the lake was a diverse feature, much like those on Earth. These conditions also apparently lasted for a very long time: some 700 million years!

“These were very different, co-existing environments in the same lake,” said Joel Hurowitz of Stony Brook University, lead author of the report. “This type of oxidant stratification is a common feature of lakes on Earth, and now we’ve found it on Mars. The diversity of environments in this Martian lake would have provided multiple opportunities for different types of microbes to survive.”

“This is a new level of detail in terms of our understanding of the chemical environment in this lake on Mars,” Hurowitz added. “It gives us a much more complete picture of the habitability of this lake.”

A simulation depicts a lake partially filling Mars Gale Crater. Illustration: NASA / JPL-Caltech.

We still don’t know if Mars did have any life (and if it did, we shouldn’t get our hopes up for anything bigger than microbial), but having a complex lake system, with warm water ranging from shallow to deep is definitely exciting. It means it could have supported several different types of microbes. Some microbes thrive in low-oxygen environments, while other prefer the opposite. Keep in mind that scientists are looking into a time when photosynthesis hadn’t even evolved on Earth, so we’re not sure what kind of microbial life Mars might have hosted.

“We’re learning that in parts of the lake and at certain times, the water carried more oxygen,” said Roger Wiens, a planetary scientist at Los Alamos National Laboratory and co-author of the study, published today in the journal Science. “This matters because it affects what minerals are deposited in the sediments, and also because oxygen is important for life. But we have to remember that at the time of Gale Lake, life on our planet had not yet adapted to using oxygen–photosynthesis had not yet been invented. Instead, the oxidation state of certain elements like manganese or iron may have been more important for life, if it ever existed on Mars. These oxidation states would be controlled by the dissolved oxygen content of the water.”

A drilled hole made by Curiosity. Image credits: NASA / JPL.

Researchers were surprised by the accuracy of the Curiosity analysis, and how much we can deduct from that. But put together, this makes a lot of sense.

“What was causing iron minerals to be one flavor in one part of the lake and another flavor in another part of the lake?” Hurowitz asked. “We had an ‘Aha!’ moment when we realized that the mineral information and the bedding-thickness information mapped perfectly onto each other in a way you would expect from a stratified lake with a chemical boundary between shallow water and deeper water.”

A hypothesized model of a redox-stratified lake in Gale crater — just like a lake on Earth. Source: NASA / JPL.

In total, Curiosity has been on Mars for over 1,700 sols (martian days, which are 24 hours, 39 minutes long), traveling 16 km from the bottom of Gale Crater towards the peak of Mount Sharp. Its main objective is determining whether Mars could have supported life, by analyzing nature and inventory of organic carbon compounds, investigating the chemical components which could serve as the building blocks of life, identifying biosignatures of life, investigating the chemical, isotopic, and mineralogical composition of the Martian surface, interpreting geological processes taking place and assessing the broad spectrum of surface radiation, which is necessary for a future manned mission to Mars.

As for whether Mars does host life now, unfortunately, that’s not an answer Curiosity is equipped to answer. We’ll have to wait a few more years for NASA’s next Mars mission to figure that one out.

Journal Reference: J. A. Hurowitz et al — Redox stratification of an ancient lake in Gale crater, Mars. DOI: 10.1126/science.aah6849

There’s a good chance Mars has liquid water

Researchers have long known that Mars has water on its surface in the form of ice, but now, after years and years of research, we might finally have the decisive clue that our planetary neighbor has liquid water on its surface. The key find was perchlorate – a substance that significantly lowers the freezing point, so that water doesn’t freeze into ice, but remains liquid and briny.

Image credits University of Copenhagen.

Image credits University of Copenhagen.

“We have discovered the substance calcium perchlorate in the soil and, under the right conditions, it absorbs water vapour from the atmosphere. Our measurements from the Curiosity rover’s weather monitoring station show that these conditions exist at night and just after sunrise in the winter,” explains Morten Bo Madsen, associate professor and head of the Mars Group at the Niels Bohr Institute at the University of Copenhagen.

Perchlorates are substances which can be produced naturally and are soluble in water. Basically, if you mix them with water, the freezing temperature of water significantly; in other words, it can get a lot colder without the water actually freezing – it becomes a sort of liquid brine. The situation on Mars is especially fit to accommodate this mixture, as researchers explain. This can also explain some of the water circulation on the Red Planet.

“When night falls, some of the water vapour in the atmosphere condenses on the planet surface as frost, but calcium perchlorate isvery absorbent and it forms a brine with the water, so the freezing point is lowered and the frost can turn into a liquid. The soil is porous, so what we are seeing is that the water seeps down through the soil. Over time, other salts may also dissolve in the soil and now that they are liquid, they can move and precipitate elsewhere under the surface,” Madsen adds.

The Curiosity Rover has previously found tantalizing clues that water once flowed on Mars. It is now believed that Mars kept its liquid water for millions of years – it also has the rounded rocks with the right chemistry to boast. But if there are indeed large quantities of perchlorate on the surface, it might mean that liquid water on Mars (or right below its surface) is much more common than previously thought.

Close-up observations have also shown characteristic of old riverbeds with rounded rocks, as well as expanses of sedimentary deposits, lying as ‘plates’ one above the other and leaning a bit toward Mount Sharp. The latter are very typical types of deposits, related to lake environments:

“These kind of deposits are formed when large amounts of water flow down the slopes of the crater and these streams of water meet the stagnant water in the form of a lake. When the stream meets the surface, the solid material carried by the stream falls down and is deposited in the lake just at the lakeshore. radually, a slightly inclined slope is built up just below the surface of the water and traces of such slanting deposits were found during the entire trip to Mount Sharp. Very fine-grained sediments, which slowly fell down through the water, were deposited right at the very bottom of the crater lake. The sediment plates on the bottom are level, so everything indicates that the entire Gale Crater may have been a large lake,” Madsen continues.

A long long time ago, some 4.5 billion years ago, Mars would have been a very different place than it is today – with a solid atmosphere and a lot of liquid water. But the atmosphere has dissipated into space, the water has also evaporated and escaped the planet and Mars no longer has a magnetic field.

So what does this mean for the possibility of finding life on Mars? Well, even though water is an essential requirement for life as we know it, water itself is not sufficient. Mars is really cold, and not protected from cosmic radiation (like Earth is), so finding life is not as likely as you’d be tempted to think. But it’s still a possibility.

Curiosity Reveals Mars isn’t Red – it’s Greyish Blue

Mars – our planetary neighbor, the Red Planet… is not actually red. The first look at what’s under Mars’s dusty red surface has revealed a clearly greyish blue rocky layer.

The Red Planet might only be Red on the surface. Image: NASA/JPL-Caltech/MSSS

Curiosity rover has begun digging at a site called Telegraph Peak, the third drilling site in outcrop at base of Mount Sharp, where Curiosity has been working for the past five months. The decision to dig there was based on previous chemical measurements. The goal of Curiosity’s digging there is to figure out how exactly Mars evolved from a wet, lush environment into the dry, arid one we see today.

“The Pahrump Hills campaign previously drilled at two other sites. The outcrop is an exposure of bedrock that forms the basal layer of Mount Sharp. Curiosity’s extended mission, which began last year after a two-year prime mission, is examining layers of this mountain that are expected to hold records of how ancient wet environments on Mars evolved into drier environments”, NASA wrote on their website.

We have known for qute a while that Mars is mostly made of silicon and oxygen (much like Earth), also containing significant quantities of iron, magnesium, aluminium, calcium, and potassium. But when researchers analyzed the blueish-grey samples extracted from Telegraph Peak using the Alpha Particle X-ray Spectrometer (APXS) on the rover’s arm and its internal Chemistry and Mineralogy (CheMin) instrument, they were surprised to see just how much silicon the sample had.

“When you graph the ratios of silica to magnesium and silica to aluminium, ‘Telegraph Peak’ is toward the end of the range we’ve seen,” Curiosity co-investigator Doug Ming, from the NASA Johnson Space Centre in the US, said in the press release. “It’s what you would expect if there has been some acidic leaching. We want to see what minerals are present where we found this chemistry.”


The first surprise came from the rocks not being red, but actually much darker.

“We’re sort of seeing a new colouration for Mars here, and it’s an exciting one to us,” Joel Hurowitz, sampling system scientist for Curiosity at NASA’s Jet Propulsion Laboratory (JPL), said in a statement.

So why are we seeing this different colouration for the rocks? The key answer here is likely “oxidation” – the reddish dust on the surface of Mars is subject to oxidation; in other words, it rusts, and turns red. The grey powder that Curiosity collected is hidden and kept safe from that process, and therefore may preserve some indication of what iron was doing, without the implication of the oxidation.

The Curiosity rover will now be journeying away from Pahrump Hills, moving up Mount Sharp to see if the same thing is happening at a higher altitude.

Crystal-Rich Rock ‘Mojave’ is Next Mars Drill Target

Curiosity is preparing for its second drill on Mars – its eyeing a rock which may have a salty story to tell.

This view from the wide-angle Hazard Avoidance Camera on the front of NASA’s Curiosity Mars Rover shows the rover’s drill in position for a mini-drill test to assess whether a rock target called “Mojave” is appropriate for full-depth drilling to collect a sample. It was taken on Jan. 13, 2015.
Image Credit: NASA/JPL-Caltech

The Mojave rock displays copious slender features, resembling rice grains which appear to be small crystals of salt. The crystals may be left overs from a salty lake from which water has evaporated. This week, Curiosity is beginning a “mini-drill” test to assess the rock’s suitability for deeper drilling, in which it would take the sample in and analyze it. However, we don’t know for sure what the crystals are… they could be something entirely different.

“The crystal shapes are apparent in the earlier images of Mojave, but we don’t know what they represent,” said Curiosity Project Scientist Ashwin Vasavada at NASA’s Jet Propulsion Laboratory, Pasadena, California. “We’re hoping that mineral identifications we get from the rover’s laboratory will shed more light than we got from just the images and bulk chemistry.”

We probably won’t know for sure until Curiosity actually takes in a sample of the rock; the rover is equipped with a Chemistry and Mineralogy instrument (CheMin) which allows it to identify specific minerals from powder. Geologists working on the project are eager to find out.

“There could be a fairly involved story here,” Vasavada said. “Are they salt crystals left from a drying lake? Or are they more pervasive through the rock, formed by fluids moving through the rock? In either case, a later fluid may have removed or replaced the original minerals with something else.”

Lozenge-shaped crystals are evident in this magnified view of a Martian rock target called “Mojave,” taken by the Mars Hand Lens Imager (MAHLI) instrument on the arm of NASA’s Curiosity Mars rover. Image Credit: NASA/JPL-Caltech/MSSS

With the Mojave analysis, Curiosity begins its third round of investigations on Mount Sharp, the central peak within Gale crater where the rover is conducting its studies. In the first stage, Curiosity drove about 360 feet (110 meters) and scouted sites ranging about 30 feet (9 meters) in elevation. Then it underwent a similar path, paying more attention to the details on its way. Mojave was the most interesting thing along its way, and naturally, scientists want to know more about it. Curiosity’s work at Pahrump Hills may include drilling one or more additional rocks before heading to higher layers of Mount Sharp. Next week, Curiosity also has a software revision planned.

“The files have already been uplinked and are sitting in the rover’s file system to be ready for the installation,” said JPL’s Danny Lam, the deputy engineering operations chief leading the upgrade process.

Following the software changes, the rover will be able to use its gyroscope-containing “inertial measurement unit” at the same time as the rover’s drill, for better capability to sense slippage of the rover during a drilling operation. Another is a set of improvements to the rover’s ability to autonomously identify and drive in good terrain. Minor tweaks are also underway.

For more information about Curiosity, visit: http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/

You can follow the mission on Facebook and Twitter at: http://www.facebook.com/marscuriosity and http://www.twitter.com/marscuriosity

Source: NASA.


NASA Rover Finds Evidence of Organic Chemistry on Mars

NASA’s Mars Curiosity Rover has discovered a tenfold spike in methane, an organic chemical which may indicate that there actually was life on Mars – or still is. The rover detected this high concentration in the atmosphere, as well as in a rock-powder sample collected by the robotic laboratory’s drill.

Curiosity on the Red Planet

Computer-generated image of Curiosity on Mars. Image credits: NASA/JPL.

Curiosity has been on the Red Planet for about 20 months, during which it has made a number of spectacular discoveries. It has found evidence of water on Mars several times, it detected organic molecules and took some stunning pictures along the way. You could easily say that the mission was a success, but Curiosity is still reporting valuable information day after day – like the discovery of organic molecule concentration.

Before you get super excited, you should know that this doesn’t necessarily mean that life existed or exists on Mars – there are also non-biological causes for this methane concentration.

“This temporary increase in methane — sharply up and then back down — tells us there must be some relatively localized source,” said Sushil Atreya of the University of Michigan, Ann Arbor, a member of the Curiosity rover science team. “There are many possible sources, biological or non-biological, such as interaction of water and rock.”

The Sample Analysis at Mars (SAM) laboratory onboard Curiosity has been used 12 times since the Rover landed on Mars to test the atmosphere of the Red Planet. Most measurements averaged at 0.7 parts per million but four measurements averaged 10 times more methane. Curiosity also detected different Martian organic chemicals in powder drilled from a rock – the first definitive detection of organics in surface materials of Mars. It’s not yet clear if these organic substances were formed on Mars or were brought by meteorites.

Organic molecules

Methane discovered on Mars may indicate that the Red Planet once harbored microbial life. Image via Wired.

Organic molecules are typically made out of Carbon and Hydrogen atoms; for example, methane has one carbon atom and four hydrogen atoms. Curiosity’s discovery doesn’t necessarily indicate that Mars had or has microbes, but it does show a chemically active planet.

“We will keep working on the puzzles these findings present,” said John Grotzinger, Curiosity project scientist of the California Institute of Technology in Pasadena. “Can we learn more about the active chemistry causing such fluctuations in the amount of methane in the atmosphere? Can we choose rock targets where identifiable organics have been preserved?”

Identifying which organic molecules are there is difficult in itself, but it’s further complicated by the presence of perchlorate minerals in Martian rocks and soils. When heated inside SAM, the perchlorates alter the structures of the organic compounds, so the identities of the Martian organics in the rock remain uncertain.

“This first confirmation of organic carbon in a rock on Mars holds much promise,” said Curiosity Participating Scientist Roger Summons of the Massachusetts Institute of Technology in Cambridge. “Organics are important because they can tell us about the chemical pathways by which they were formed and preserved. In turn, this is informative about Earth-Mars differences and whether or not particular environments represented by Gale Crater sedimentary rocks were more or less favorable for accumulation of organic materials. The challenge now is to find other rocks on Mount Sharp that might have different and more extensive inventories of organic compounds.”

The findings haven’t been officially published in a peer reviewed study, but the results were discussed on Tuesday at the American Geophysical Union’s convention in San Francisco. For copies of the new Science papers about Mars methane and water, visit:


First Rock Dating Experiment Performed on Mars

Dating rocks is not really something new – it’s been conducted on Earth for decades now; researchers have also determined the age of rocks from outer space, but the experiments always took place on Earth. Now, for the first time, this procedure took place on Mars.


An image from the Curiosity rover, showing the drilling of the second sample. Credit: NASA/JPL-Caltech

The work, led by geochemist Ken Farley of the California Institute of Technology (Caltech) could provide not only valuable information about the Martian geology, but give aid in the search for life on Mars.

With the huge importance of the Curiosity mission, every detail was planned in detail months before the shuttle was launched, but shortly before the rover left Earth in 2011, NASA’s participating scientist program asked researchers from all over the world to submit new ideas for experiments that could be performed with the already installed instruments. Farley was one of the 29 selected participants and he submitted a proposal to conduct a series of techniques fairly similar to those used on Earth do date rocks. His proposal was accepted, and in a paper published this week in the journal Science Express he and his colleagues conducted the first age determinations performed on another planet.

Before this geochronology experiment took place, scientists were using the so-called “crater counting” method, which had estimated the age of Gale Crater and its surroundings to be between 3.6 and 4.1 billion years old. Crater counting relies on a surprisingly simple fact: since Mars is constantly bombarded by meteorites, an area with more craters is going to be older; researchers have developed a way to transpose the number of craters into an estimated age.

With Farley’s method, the Curiosity rover calculated the age of the mudstone at Gale Crater to be about 3.86 to 4.56 billion years old – incredibly close to initial estimates!

“In one sense, this is an utterly unsurprising result—it’s the number that everybody expected,” Farley says.

Indeed, it seems absolutely shocking that such a simple method with so many uncertainties and estimations can be so accurate.

“What was surprising was that our result—from a technique that was implemented on Mars with little planning on Earth—got a number that is exactly what crater counting predicted,” Farley says. “MSL instruments weren’t designed for this purpose, and we weren’t sure if the experiment was going to work, but the fact that our number is consistent with previous estimates suggests that the technique works, and it works quite well.”

However, there is some uncertainty with this method as well. Since mudstone is a sedimentary rock, it is heavily subjected to erosion and other surface processes. The age of the sample drilled by Curiosity really is the age of the rock that was still left standing after these processes, and while the entire crater was almost certainly a lake at some point in its existence (and was capable of supporting life), it’s impossible with this method to know when this was happening.

Via CalTech.

Flowing water found on Mars – suggests life exists in the underground

Researchers have reported dark streaks near the equator of Mars, hinting at surprisingly large quantities of flowing water. If true, this could be extremely important for life on Mars, and potentially even establishing research bases.

Water on Mars – yes

If you don’t know that rivers and lakes were fairly common on Mars a long time ago, you haven’t been reading a lot of ZME Science. We’ve written tons of articles about water on Mars, with information coming most notably from the Curiosity Rover, Opportunity Rover, and from interpreted pictures. With the development of technology it became fairly simple to observe the river-like valleys which attest almost beyond the shadow of a doubt the flow of water on ancient Mars. However, the planet has changed dramatically in the past billion years (hey, who hasn’t?).

Today, the atmosphere is too thin to support liquid water on the surface for long. However, there are things which suggest that water may still run on the surface from time to time. The first clear signs that this was happening occurred in 2011, when the Mars Reconnaissance Orbiter (MRO) spacecraft observed dark streaks a few metres wide that popped up and widened during the warm season, only to shrink in cooler seasons. The same cycle was observed up to the end of 2013.

“This behaviour is easy to understand if these are seeps of water,” says planetary scientist Alfred McEwen of the University of Arizona in Tucson, who led that study. “Water will darken most soils.”

The streaks were observed in seven different points, located in the relative proximity of the Martian equator. They probably came from the ice trapped about a metre below the surface; the MRO has in fact spotted fresh water occurring following meteoric impacts, which seems to support this theory.

Life on Mars? Probably

Now, McEwen and his colleagues have  found 12 more sites; just so you can make an idea, each site has hundreds or thousands of such streaks. The interesting thing is the source. The temperatures there are relatively warm throughout the year, so without a constant source, the subsurface ice would probably already have sublimated. So where does the ice/water come from?

His theory is that water may come from groundwater deep in the crust, which, if true, has major implications for life on Mars – basically, there’s no good reason why life shouldn’t exist in the Martian underground.

“The subsurface is probably the best place to find present-day life if it exists at all because it is protected from the radiation and temperature extremes,” he says. “Maybe some of that water occasionally leaks out onto the surface, where we could see evidence for that subsurface life.”

Hard to explore

However, even if this is the case, it will be extremely hard to explore these areas, as any spacecraft has to be sterilized extremely carefully, to prevent the possibility of contamination.

“You wouldn’t want to send a dirty spacecraft to these places because you’d have the potential to not discover what you’re looking for, but what you took with you,” says John Rummel, chair of COSPAR’s panel on planetary protection.

But it’s not as simple as rubbing the shuttle with alcohol – the sterilization process is very complicated, including heat, hydrogen peroxide vapour or ionizing radiation to kill off as much Earth life as possible. This would significantly raise the costs of any mission in any of those areas.

Scientific Reference:

McEwen, A. S. et al. Nature Geosci. http://dx.doi.org/10.1038/ngeo2014 (2013).

Evidence of ancient lake found on Mars

NASA’s Curiosity rover has come up with yet another remarkable discovery – evidence of an ancient, freshwater lake, with water that was likely very similar to that of today’s Earth lakes. The feature is thought to be part of a longstanding aquatic environment which could have supported simple life forms.

This illustration depicts a concept for the possible extent of an ancient lake inside Gale Crater. Image Credit: NASA/JPL-Caltech/MSSS

This illustration depicts a concept for the possible extent of an ancient lake inside Gale Crater.
Image Credit: NASA/JPL-Caltech/MSSS

“In March, we did know that we had a lake, but what we weren’t sure of was how big it was and how long it lasted, and also we were not sure about the broader geological context that supports the presence of lakes coming and going for a very long time,” said John Grotzinger – a Caltech planetary geologist who is the chief scientist of the Curiosity rover missionsaid in an interview. He is the author of the scientific paper called “A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars.”

“This is really similar to an Earth environment,” he said at the AGU news conference.

Scientists have known for a while that in its earlier days, Mars looked a lot more like the Earth than it does now. There have been several clear indications of water on Mars, but this is the best evidence yet that Mars had swimming holes that stuck around for thousands or perhaps millions of years. It was almost certainly very cold, but still habitable. The former lake’s size was comparable to that of the New York finger lakes – approximately 40 km in length and less than 10 in width. The freshwater may have sometimes frozen over, but the research shows that the lake was not some momentary feature, but rather was part of a long-lasting habitable environment that included rivers and groundwater – very favorable conditions of supporting life.

“If we put microbes from Earth and put them in this lake on Mars, would they survive? Would they survive and thrive? And the answer is yes,” said Grotzinger.

mars lake 2

Curiosity on Mars: The rover nears a ridge named “Cooperstown,” a possible site for contact inspection with tools on the robotic arm. Credits: NASA.

However, Curiosity won’t be able to provide more information on the potential (former) habitability of the lake bed. If microorganisms did inhabit the lake, it’s likely that they greatly resemble chemolithoautotrophs – mineral eaters which typically thrive in exotic environments such as caves or deep sea underwater vents – and Curiosity lacks the tools to answer these issues.

But researchers are hyped about this discovery nonetheless.

“I’m most excited about the nature of the water,” said Jim Bell, an Arizona State University scientist who has worked with the cameras on Curiosity as well as two precursor rovers, Spirit and Opportunity, and is a co-author of four of the new papers. “Previous results from Spirit and Opportunity pointed to very acidic water, but what we’re seeing in Gale Crater is evidence of fresh water. Very neutral. Drinkable.”

In the time it has spent on the Red Planet, the brave rover has provided incredibly valuable information. In a little more than a year on the Red Planet, the mobile Mars Science Laboratory has determined the age of a Martian rock, found evidence the planet could have sustained microbial life, taken the first readings of radiation on the surface, and shown how natural erosion could reveal the building blocks of life.

Curiosity finds water on Mars

After finding no methane in the Martian atmosphere, Curiosity has shown that the soil and dust on the surface of the Red Planet contain a few percent water, judging by weight. Yes, yes, I know, Curiosity has found signs that water flowed on Mars sometime during its past (1, 2, 3), but this time, it has found actual, direct evidence of water.

Water on Mars


The rover found that judging by weight, the surface of Mars contains some 2 percent water – this could mean that future, pioneer astronauts could extract 1 liter of water from 0.05 cubic meters. The sample Curiosity analyzed also revealed significant carbon dioxide and sulphur compounds.

“One of the most exciting results from this very first solid sample ingested by Curiosity is the high percentage of water in the soil,” said Laurie Leshin, lead author of one paper and dean of the School Science at Rensselaer Polytechnic Institute. “About 2 percent of the soil on the surface of Mars is made up of water, which is a great resource, and interesting scientifically.”

The results were part of a five-paper special edition on the Curiosity mission and were published today in Science. They don’t mention this, but some of you might find interesting to know that most of this water is probably frozen; in its warmest areas, Mars is about as cold as Alaska, and in its coldest areas, it’s like anything else on Earth.

The technical achievement in itself is huge. Curiosity is the first man-made equipment on Mars which can gather and process samples of soil. In order to do this, the rover employs the Sample Analysis at Mars (SAM) instrument suite, which includes a gas chromatograph, a mass spectrometer and a tunable laser spectrometer. These tools are able to identify a wide range of chemical compounds and also determine the ratios of different isotopes.

curiosity 2

“This work not only demonstrates that SAM is working beautifully on Mars, but also shows how SAM fits into Curiosity’s powerful and comprehensive suite of scientific instruments,” said Paul Mahaffy, principal investigator for SAM at NASA’s Goddard Space Flight Center in Greenbelt, Md. “By combining analyses of water and other volatiles from SAM with mineralogical, chemical and geological data from Curiosity’s other instruments, we have the most comprehensive information ever obtained on Martian surface fines. These data greatly advance our understanding surface processes and the action of water on Mars.”

Bad news for manned missions

SAM also detected some organic materials in the rock sample as well – carbon containing chemicals that are the building blocks of life on Earth; but don’t get your hopes up – these are simple, chlorinated organics that likely have nothing to do with Martian life. As a matter of fact, they are probably the result of forms of life which came from Earth and reacted with a toxic chemical called perchlorate. NASA’s Phoenix lander spotted perchlorate near the North Pole, and now Curiosity spotted it near the equator, so the substance is probably spread evenly across the planet. The presence of this chemical is an obstacle future missions will have to overcome.

“Perchlorate is not good for people. We have to figure out, if humans are going to come into contact with the soil, how to deal with that,” she said. “That’s the reason we send robotic explorers before we send humans — to try to really understand both the opportunities and the good stuff, and the challenges we need to work through,” Leshin added.

A very Earth-like igneous rock

igneous rock

Curiosity is more than a one-trick pony – it’s not only about analyzing the possibility of life on Mars, it’s also about understanding the geologic setting of the planet. Another one of the five papers detailed a rock found in October 2012 – an igneous type of rock, which was never before seen on Mars, but is rather common on Earth, on oceanic islands or where the crust is thinning out.

“Of all the Martian rocks, this one is the most Earth-like. It’s kind of amazing,” said Curiosity lead scientist John Grotzinger, a geologist at the California Institute of Technology in Pasadena. “What it indicates is that the planet is more evolved than we thought it was, more differentiated.”

Chemical tests conducted on the pyramid rock showed that it is highly enriched in sodium and potassium, making it chemically alkaline. Geologists are now fairly certain this is a type of basalt called mugearite. However, despite the massive implications this rock can carry, researchers don’t want to get carried away, as this is only one sample and may be an exception; still, if it isn’t, than this would put the entire Gale Crater in a new perspective, and would indicate that the inside processes and chemistry of Mars are far more similar to Earth than what was previously believed.

Curiosity finds no methane on Mars, surprises NASA

A lab exemplification of the measurement chamber inside the Tunable Laser Spectrometer, an instrument that is part of the Sample Analysis at Mars investigation on NASA's Curiosity rover.

A lab exemplification of the measurement chamber inside the Tunable Laser Spectrometer, an instrument that is part of the Sample Analysis at Mars investigation on NASA’s Curiosity rover.

It’s been a while since we posted something about the Curiosity rover – now, Curiosity has reported that the Martian atmosphere lacks methane. This is a surprise to researchers because previous data seemed to indicate the contrary.

The 4 wheel laboratory conducted extensive tests for traces of Martian methane, and the results were conclusive; the existence of methane would be a good indication of life on Mars, though it can be produced without life, and life can also exist without producing it.

“This important result will help direct our efforts to examine the possibility of life on Mars,” said Michael Meyer, NASA’s lead scientist for Mars exploration. “It reduces the probability of current methane-producing Martian microbes, but this addresses only one type of microbial metabolism. As we know, there are many types of terrestrial microbes that don’t generate methane.”

Curiosity samples the Martian atmosphere for methane 6 times, and given the sensibility of the device, NASA researchers estimate that the amount of methane in the Martian atmosphere today must be no more than 1.3 parts per billion.

“It would have been exciting to find methane, but we have high confidence in our measurements, and the progress in expanding knowledge is what’s really important,” said the report’s lead author, Chris Webster of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We measured repeatedly from Martian spring to late summer, but with no detection of methane.”

The highest concentration detected by Curiosity suggests that methane enters the Martian atmosphere 50 million times less than the rate of methane entering Earth’s atmosphere. This is also suggestive because if methane existed in the past on Mars, it would also probably be there now.

“There’s no known way for methane to disappear quickly from the atmosphere,” said one of the paper’s co-authors, Sushil Atreya of the University of Michigan, Ann Arbor. “Methane is persistent. It would last for hundreds of years in the Martian atmosphere. Without a way to take it out of the atmosphere quicker, our measurements indicate there cannot be much methane being put into the atmosphere by any mechanism, whether biology, geology, or by ultraviolet degradation of organics delivered by the fall of meteorites or interplanetary dust particles.”


These people want to go to Mars – and never come back

Ever since 2010, I’ve been telling you about a group of scientists and investors which wants to send people to Mars – on a one way trip, that is. But in early 2013, this took a huge step forward, materializing in the form of Mars One – a non-profit organization that plans to establish a permanent human colony on Mars by 2023.

Since they started receiving applications, they’ve received over 165.000 of them – and that’s not really surprising, considering that they asked for people over 18, with a strong knowledge of English, and the only attributes required are adaptability, curiosity, ability to trust, creativity and resourcefulness.

A few dozens of these aspiring Martians got together in Washington for the “Million Martian Meeting.” A panel of four applicants answered questions from the audience about why they want to go to Mars without a return ticket. So who wants to go to Mars anyway?
mars one 1

The People

Aaron Hamm, 29, is a hotel manager, but going to Mars is “literally something I’ve wanted forever,” he said at the meeting.

Leila Zucker, 45, is a married emergency room doctor. “Since I was a little kid, all I wanted was to be a doctor and travel in space,” Zucker said in her application video. She even composed a song about her goal: “We’re about to take off for the Red Planet Mars because Mars One leads the way to the stars,” she sang at the meeting.

mars one 2

Ok…Austin Bradley, 32, is a physics student and former imagery analyst and paratrooper for the U.S. army. He’s the one with the green hair and the antennae – but he claims his ambition is serious.

“I always wanted to apply for NASA,” he said, but now he sees Mars One as his ticket to space.

The risks

This mission, though not impossible by any standards, seems a little shaky from the start. Just the fact that you’re taking people with no (or minimum) experience, training them, then there’s the launch, the six month travel time, the landing… it seems pretty hard to do; and that’s even before they have to start living on the Red Planet!

They participants were asked exaclty what kind of risks they were willing to take – personally, I found their answers pretty shocking.

“As long as there’s a small possibility to do something great, I think it’s worth the risk,” he said., Sweeney said, admitting he would go even with a 1 in 100 chance of living for 2 years.

Zucker said she would take a 50-50 chance of surviving two years, or a 1-in-100 chance for surviving 20 years. Bradley and Hamm said they can cope with small chances as well.

“It was always a one-way trip,” Bradley said.

So what do you think? Would you sign up for such a deal?

Curiosity rover snaps a video of Martian moonrise

The otherwordly new video features one of the two Martian moons – Phobos, as it rises on the sky. Even though the movie only has 32 seconds, the action actually took place over the course of 27 minutes.

Mars has two moons: Phobos (which is just 22 km wide on average), and Deimos, which is even smaller. They are believed to be asteroids trapped a long time ago by the Martian gravitational field.

This video isn’t the first from Curiosity to represent Phobos – just five weeks after it landed on Mars, it sed its workhorse MastCam camera to photograph the moon as it crossed the face of the sun, covering a small fraction of the star.

The Curiosity rover landed inside a geological feature called Gale Crater last August, kicking off a planned two-year surface mission to find out if the Red Planet was ever able to support (microbial) life. So far, the mission was a great success, as the rover already showed that a site called Yellowknife Bay was indeed habitable billions of years ago.


Via WikiCommons