Opportunity Just Saw its 5,000th Sunrise on Mars

NASA's Mars Exploration Rover Opportunity recorded the dawn of the rover's 4,999th Martian day, or sol, with its Panoramic Camera (Pancam) on Feb. 15, 2018, yielding this processed, approximately true-color scene. Credits: NASA/JPL-Caltech/Cornell/Arizona State Univ./Texas A&M

It’s been a time of milestones for Mars rovers lately! Last month (on January 26th, 2018), NASA announced that the Curiosity rover had spent a total of 2,000 days on Mars, which works out to 5 years, 5 months and 21 days. This was especially impressive considering that the rover was only intended to function on the Martian surface for 687 days (a little under two years).

But when it comes to longevity, nothing has the Opportunity rover beat! Unlike Curiosity, which relied on a Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) for power, the solar-powered Opportunity recently witnessed its five-thousandth sunrise on Mars. This means that the rover has remained in continuous operation for 5000 sols, which works out to 5137.46 Earth days.

This five-thousandth sunrise began on Friday, Feb. 16th, 2018 – roughly 14 Earth years (and 7.48 Martian years) after the rover first landed. From its position on the western rim of the Endeavour Crater, the sunrise appeared over the basin’s eastern rim, about 22 km (14 mi) away. This location, one-third of the way down “Perseverance Valley”, is more than 45 km (28 mi) from Opportunity’s original landing site.

Mosaic view looking down from inside the upper end of “Perseverance Valley” on the inner slope of Endeavour Crater’s western rim. Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Ken Kremer/kenkremer.com

This is especially impressive when you consider that the original science mission was only meant to last 90 sols (92.47 Earth days) and NASA did not expect the rover to survive its first Martian winter. And yet, the rover has not only survived all this time, it continues to send back scientific discoveries from the Red Planet. As John Callas, the Opportunity Project Manager at NASA’s Jet Propulsion Laboratory, explained in a NASA press release:

“Five thousand sols after the start of our 90-sol mission, this amazing rover is still showing us surprises on Mars… We’ve reached lots of milestones, and this is one more, but more important than the numbers are the exploration and the scientific discoveries.”

For instance, the rover has provided us with 225,000 images since its arrival, and revealed that ancient Mars was once home to extensive groundwater and surface water. Beginning in 2008, it began working its way across the Endeavour Crater in order to get a glimpse deeper into Mars’ past. By 2011, it had reached the crater’s edge and confirmed that mineral-rich water once flowed through the area.

At present, researchers are using Opportunity to investigate the processes that shaped Perseverance Valley, an area that descends down the slope of the western rim of Endeavour Crater. Here too, Opportunity has learned some fascinating things about the Red Planet. For instance, the rover has conducted observations of possible “rock stripes” in the valley, which could be indicative of its valley’s origin.

*Textured rows on the ground in this portion of “Perseverance Valley” are under investigation by NASA’s Mars Exploration Rover Opportunity. Credits: NASA/JPL-Caltech*

These stripes are of interest to scientists because of the way they resemble rock stripes that appear on mountain slopes here on Earth, which are the result of repeated cycles of freezing and thawing on wet soil. On Mauna Kea, for example, soil freezes every night, but is often dry due to the extreme elevation. This causes soils that have high concentrations of silt, sand and gravel to expand, pushing the larger particles up.

These particles then form stripes as they fall downhill, or are moved by wind or rainwater, and cause the ground to expand less in this space. This process repeats itself over and over, creating a pattern that leads to distinct stripes. As Opportunity observed, there are slopes within the Perseverance Valley where soil and gravel particles appear to have formed into rows that run parallel to the slope, alternating between rows that have more and less gravel.

In the case of the Perseverance Valley’s stripes, scientists are not sure how they formed, but think they could be the result of water, wind, downhill transport, other processes, or a combination thereof. Another theory posits that features like these could be the result of changes in Mars tilt (obliquity) which happen over the course of hundreds of thousands of years.

During these periods, Mars’ axial tilt increases to the point where water frozen at the poles will vaporize and become deposited as snow or frost nearer to the equator. As Ray Arvidson, the Opportunity Deputy Principal Investigator at Washington University, explahttps://www.nasa.gov/feature/jpl/long-lived-mars-rover-opportunity-keeps-finding-surprisesined:

“One possible explanation of these stripes is that they are relics from a time of greater obliquity when snow packs on the rim seasonally melted enough to moisten the soil, and then freeze-thaw cycles organized the small rocks into stripes. Gravitational downhill movement may be diffusing them so they don’t look as crisp as when they were fresh.”

Stone stripes on the side of a volcanic cone on Mauna Kea, Hawaii, which are made of small rock fragments that are aligned downhill. These are formed when freeze-thaw cycles lift them out of the finer-grained regolith and move them to the sides, forming stone stripes. Credits: Washington University in St. Louis/NASA

Having the chance to investigate these features is therefore quite the treat for the Opportunity science team. “Perseverance Valley is a special place, like having a new mission again after all these years.” said Arvidson. “We already knew it was unlike any place any Mars rover has seen before, even if we don’t yet know how it formed, and now we’re seeing surfaces that look like stone stripes. It’s mysterious. It’s exciting. I think the set of observations we’ll get will enable us to understand it.”

Given the state of the Martian surface, it is a safe bet that wind is largely responsible for the rock stripes observed in Perseverance Valley. In this respect, they would be caused by sand blown uphill from the crater floor that sorts larger particles into rows parallel to the slope. As Robert Sullivan, an Opportunity science-team member of Cornell University, explained:

“Debris from relatively fresh impact craters is scattered over the surface of the area, complicating assessment of effects of wind. I don’t know what these stripes are, and I don’t think anyone else knows for sure what they are, so we’re entertaining multiple hypotheses and gathering more data to figure it out.”

Despite being in service for a little over 14 years, and suffering its share of setbacks, Opportunity is once again in a position to reveal things about Mars’ past and how it evolved to become what it is today. Never let it be said that an old rover can’t reveal new secrets! If there’s one thing Opportunity has proven during its long history of service on Mars, it is that the underdog can make some of the greatest contributions.

Further Reading: NASA, NASA (2)

February 14, 2018February 14, 2018 by Matt Williams

Mars 2020 Rover is Going to be Taking a Chunk of Mars Back to… Mars?

This artist's rendition depicts NASA's Mars 2020 rover studying its surroundings. Credit: NASA

In July of 2020, the Mars 2020 rover – the latest from NASA’s Mars Exploration Program – will begin its long journey to the Red Planet. Hot on the heels of the Opportunity and Curiosity rovers, the Mars 2020 rover will attempt to answer some of the most pressing questions we have about Mars. Foremost among these is whether or not the planet had habitable conditions in the past, and whether or not microbial life existed there.

To this end, the Mars 2020 rover will obtain drill samples of Martian rock and set them aside in a cache. Future crewed missions may retrieve these samples and bring them back to Earth for analysis. However, in a recent announcement, NASA indicated that a piece of a Martian meteor will accompany the Mars 2020 rover back to Mars, which will be used to calibrate the rover’s high-precious laser scanner.

This laser scanner is known as the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument. The laser’s resolution is capable of illuminating even the finest features in rock samples, which could include fossilized microorganisms. But in order to achieve this, the laser requires a calibration target so that the science team can fine-tune its settings.

Mounted on the rover’s robotic arm, SHERLOC uses spectrometers, a laser and a camera to search for organics and minerals that have been altered by watery environments and may be signs of past microbial life. Credit: NASA

Ordinarily, these calibration targets involve pieces of rock, metal or glass, samples that are the result of a complex geological history. However, when addressing the SHERLOC’s calibration needs, JPL scientists came up with a rather innovative idea. For billions of years, Mars has experienced impacts that have sent pieces of its surface into orbit. In some cases, those pieces came to Earth in the form of meteorites, some of which have been identified.

While these meteorites are rare and not identical to the geologically diverse samples the Mars 2020 rover will collect, they are well-suited for target practice. As Luther Beegle of JPL, the principle investigator for SHERLOC, said in a recent NASA press statement:

“We’re studying things on such a fine scale that slight misalignments, caused by changes in temperature or even the rover settling into sand, can require us to correct our aim. By studying how the instrument sees a fixed target, we can understand how it will see a piece of the Martian surface.”

In this respect, the Mars 2020 rover is in good company. For example, Curiosity’s used its Chemistry and Camera (ChemCham) instrument – which relies on laser-induced breakdown spectroscopy (LIBS) – to determine the elemental compositions of rock and soil samples it has obtained. Similarly, the Opportunity rover’s Miniature Thermal Emission Spectrometer (Mini-TES) allowed this rover to detect the composition of rocks from a distance.

*Rohit Bhartia of NASA’s Mars 2020 mission holds a slice of a meteorite scientists have determined came from Mars. Credit: NASA/JPL-Caltech*

However, SHERLOC is unique in that it will be the first instrument deployed to Mars that uses Raman and fluorescence spectroscopy. Raman spectroscopy consists of subjecting materials to light in the visible, near infrared, or near ultraviolet range and measuring how the photons respond. Based on how their energy levels shift up or down, scientists are able to determine the presence of certain elements.

Fluorescence spectroscopy relies on ultraviolet lasers to excite the electrons in carbon-based compounds, which causes chemicals that are known to form in the presence of life (i.e. biosignatures) to glow. SHERLOC will also photograph the rocks it studies, which will allow the science team to map the chemical signatures it finds across the surface of Mars.

For their purposes, the SHERLOC team needed a sample that would be solid enough to withstand the intense vibrations caused by launch and landing. They also needed one that contained the right chemicals to test SHERLOC’s sensitivity to biosignatures. With the help of the Johnson Space Center and the Natural History Museum in London, they ultimately decided on a sample from the Sayh al Uhaymir 008 meteorite (aka. SaU008).

This meteorite, which was found in Oman in 1999, was more rugged that other samples and could be sliced without the rest of the meteorite flaking. As a result, SaU008 will be the first Martian meteorite sample that helps scientists look for past signs of life on Mars. It will also be the first Martian meteorite to have a piece of itself returned to the surface of Mars – though technically not the first to be sent back.

*A slice of a meteorite scientists have determined came from Mars placed inside an oxygen plasma cleaner, which removes organics from the outside of surfaces. Credit: NASA/JPL-Caltech*

That honor goes to Zagami, a meteorite retrieved in Nigeria in 1962, which had a piece of itself sent back to Mars aboard the Mars Global Surveyor (MGS) in 1999. That mission ended in 2007, so this chunk has been floating around in orbit of Mars ever since. In addition, the team behind Mars 2020‘s SuperCam instrument will also be adding a Martian meteorite for their own calibration tests.

Along with bits of SaU008, the Mars 2020 payload will include samples of advanced materials. Aside from also being used to calibrate SHERLOC, these materials will be tested to see how they hold up to Martian weather and radiation. If they prove to be tough enough to survive on the Martian surface, these materials could be used in the manufacture of space suits, gloves and helmets for future astronauts.

As Marc Fries, a SHERLOC co-investigator and curator of extraterrestrial materials at Johnson Space Center, put it:

“The SHERLOC instrument is a valuable opportunity to prepare for human spaceflight as well as to perform fundamental scientific investigations of the Martian surface. It gives us a convenient way to test material that will keep future astronauts safe when they get to Mars.”

With every robotic mission sent to Mars, NASA and other space agencies are working towards the day when astronauts’ boots will finally touch down on the Red Planet. When the first crewed mission to Mars are conducted (currenty scheduled for the 2030s), they will be following in the tracks of some truly intrepid robotic explorers!

Further Reading: NASA

February 5, 2018 by Matt Williams

ESA’s ExoMars has Completed its Aerobraking Maneuvers to Bring it Into a Circular 400 km Orbit Around Mars

Artist’s impression depicting the separation of the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, from the Trace Gas Orbiter, and heading for Mars. Credit: ESA/D. Ducros

In March of 2016, the European Space Agency (ESA) launched the ExoMars (Exobiology on Mars) mission into space. A joint project between the ESA and Roscosmos, this two-part mission consisted of the Trace Gas Orbiter (TGO) and the Schiaparelli lander, both of which arrived in orbit around Mars in October of 2016. While Schiaparelli crashed while attempting to land, the TGO has gone on to accomplish some impressive feats.

For example, in March of 2017, the orbiter commenced a series of aerobraking maneuvers, where it started to lower its orbit to enter Mars’ thin atmosphere and slow itself down. According to Armelle Hubault, the Spacecraft Operations Engineer on the TGO flight control team, the ExoMars mission has made tremendous progress and is well on its way to establishing its final orbit around the Red Planet.

TGO’s mission has been to study the surface of Mars, characterize the distribution of water and chemicals beneath the surface, study the planet’s geological evolution, identify future landing sites, and to search for possible biosignatures of past Martian life. Once it has established its final orbit around Mars – 400 km (248.5 mi) from the surface – the TGO will be ideally positioned to conduct these studies.

*Visualization of the ExoMars mission’s Trace Gas Orbiter conducting aerobraking maneuvers to March of 2018. Credit: ESA*

The ESA also released a graphic (shown above) demonstrating the successive orbits the TGO has made since it began aerobraking – and will continue to make until March of 2018. Whereas the red dot indicates the orbiter (and the blue line its current orbit), the grey lines show successive reductions in the TGO’s orbital period. The bold lines denote a reduction of 1 hour while the thin lines denote a reduction of 30 minutes.

Essentially, a single aerobraking maneuver consist of the orbiter passing into Mars’ upper atmosphere and relying on its solar arrays to generate tiny amounts of drag. Over time, this process slows the craft down and gradually lowers its orbit around Mars. As Armelle Hubault recently posted on the ESA’s rocket science blog:

“We started on the biggest orbit with an apocentre (the furthest distance from Mars during each orbit) of 33 200 km and an orbit of 24 hr in March 2017, but had to pause last summer due to Mars being in conjunction. We recommenced aerobraking in August 2017, and are on track to finish up in the final science orbit in mid-March 2018. As of today, 30 Jan 2018, we have slowed ExoMars TGO by 781.5 m/s. For comparison, this speed is more than twice as fast as the speed of a typical long-haul jet aircraft.”

Earlier this week, the orbiter passed through the point where it made its closest approach to the surface in its orbit (the pericenter passage, represented by the red line). During this approach, the craft dipped well into Mars’ uppermost atmosphere, which dragged the aircraft and slowed it down further. In its current elliptical orbit, it reaches a maximum distance of 2700 km (1677 mi) from Mars (it’s apocenter).

*Visualization of the ExoMars Trace Gas Orbiter aerobraking at Mars. Credit: ESA/ATG medialab*

Despite being a decades-old practice, aerobraking remains a significant technical challenge for mission teams. Every time a spacecraft passes through a planet’s atmosphere, its flight controllers need to make sure that its orientation is just right in order to slow down and ensure that the craft remains stable. If their calculations are off by even a little, the spacecraft could begin to spin out of control and veer off course. As Hubault explained:

“We have to adjust our pericentre height regularly, because on the one hand, the martian atmosphere varies in density (so sometimes we brake more and sometimes we brake less) and on the other hand, martian gravity is not the same everywhere (so sometimes the planet pulls us down and sometimes we drift out a bit). We try to stay at about 110 km altitude for optimum braking effect. To keep the spacecraft on track, we upload a new set of commands every day – so for us, for flight dynamics and for the ground station teams, it’s a very demanding time!”

The next step for the flight control team is to use the spacecraft’s thrusters to maneuver the spacecraft into its final orbit (represented by the green line on the diagram). At this point, the spacecraft will be in its final science and operation data relay orbit, where it will be in a roughly circular orbit about 400 km (248.5 mi) from the surface of Mars. As Hubault wrote, the process of bringing the TGO into its final orbit remains a challenging one.

“The main challenge at the moment is that, since we never know in advance how much the spacecraft is going to be slowed during each pericentre passage, we also never know exactly when it is going to reestablish contact with our ground stations after pointing back to Earth,” she said. “We are working with a 20-min ‘window’ for acquisition of signal (AOS), when the ground station first catches TGO’s signal during any given station visibility, whereas normally for interplanetary missions we have a firm AOS time programmed in advance.”

*Artist’s impression of the ESA’s Exomars 2020 rover, which is expected to land on the surface of Mars by the Spring of 2o21. Credit:ESA*

With the spacecraft’s orbital period now shortened to less than 3 hours, the flight control team has to go through this exercise 8 times a day now. Once the TGO has reached its final orbit (by March of 2018), the orbiter will remain there until 2022, serving as a telecommunications relay satellite for future missions. One of its tasks will be to relay data from the ESA’s ExoMars 2020 mission, which will consist of a European rover and a Russian surface platform being deployed the surface of Mars in the Spring of 2021.

Along with NASA’s Mars 2020 rover, this rover/lander pair will be the latest in a long line of robotic missions looking to unlock the secrets of Mars past. In addition, these missions will conduct crucial investigations that will pave the way for eventual sample return missions to Earth, not to mention crewed to the surface!

Further Reading: ESA

February 1, 2018 by Matt Williams

Curiosity has Lasted More than 2,000 Days on Mars, Triple its Original Mission Plan

Mosaic image of the Curiosity rover on Mars, which recently turned up more evidence that supports the idea that the planet was once habitability. Credit: NASA/JPL-Caltech/MSSS.

On August 5th, 2012, after spending over 8 months in space, NASA’s Curiosity rover landed on Mars. As part of the NASA Mars Science Laboratory (MSL) mission, and the latest in a series of rovers deployed to the Martian surface, Curiosity had some rather ambitious research goals. In addition to investigating Mars’ climate and geology, the rover was also tasked with revealing more about Mars’ past and determining if it ever supported microbial life.

And recently, the Curiosity rover hit another major milestone in its exploration of the Red Planet. As of January 26th, 2018 the rover has spent a total of 2,000 days on Mars, which works out to 5 years, 5 months and 21 days – or 1947 Martian days (sols). That’s especially impressive when you consider that the mission was only meant to last 687 days (668 sols), or just little under 2 years.

In all that time, the Curiosity rover has accomplished some major feats and has the scars to prove it! Some of it’s wheels have become teared, holed and cracked and its drill has been pushed almost to the point of breaking. And yet, Curiosity is still hard at work pushing itself up a mountain – both literally and figuratively! The rover has also managed to exceed everyone’s expectations.

*MRO image of Gale Crater illustrating the landing location and trek of the Rover Curiosity. Credits: NASA/JPL, illustration, T.Reyes*

As Ashwin Vasavada, the MSL Project Scientist, told Universe Today via email:

“In terms of challenges, the first 2000 days of Curiosity’s mission went better than I could have hoped. For much of the time, the rover remained as capable as the day it landed. We had a scare in the first year when a memory fault triggered additional problems and nearly resulted in the loss of the mission. We famously wore down our wheels pretty early, as well, but since then we’ve kept that under control. In the last year, we’ve had a major problem with our drill. That’s the only major issue currently, but we believe we’ll be back to drilling in a month or so. If that works out, we’ll amazingly be back to having all systems ready for science!”

As of the penning of this article, the rover is climbing Mount Sharp in order to collect further samples from Mars’ past. Also known as Aeolis Mons, this mountain resides in the center of the Gale Crater where Curiosity landed in 2012 and has been central to Curiosity’s mission. Standing 5,500 meters (18,000 ft) above the valley floor, Mount Sharp is believed to have formed from sediment that was slowly deposited by flowing water over billions of years.

This is all in keeping with current theories about how Mars once had a denser atmosphere and was able to sustain liquid water on its surface. But between 4.2 and 3.7 billion years ago, this atmosphere was slowly stripped away by solar wind, thus turning Mars into the cold and desiccated place that we know today. As a result, the study of Mount Sharp was always expected to reveal a great deal about Mars’ geological evolution.

*Image of Mount Sharp taken by the Curiosity rover on Aug. 23rd, 2012. The layers at the base of Mt. Sharp show the geological history of Mars. Credit: NASA/JPL-Caltech/MSSS.*

In it’s first year, Curiosity achieved a major milestone when the rover obtained drill samples from low-lying areas that indicated that lakes and streams existed in the Gale Crater between 3.3 to 3.8 billion years ago. In addition, the rover has also obtained ample evidence that the crater once had all the chemical elements and even a chemical source of energy needed for microbial life to exist.

“NASA’s charge to our mission was to determine whether Mars ever had conditions suitable for life,” said Vasavada. “Success was not a foregone conclusion. Would we arrive safely? Would the scientific instruments work? Would the area we chose for the landing site hold the clues we were looking for? For me, meeting each of these objectives are the highlights of the mission. I’ll never forget witnessing the launch, or nervously waiting for a safe touchdown. Discovering an ancient, freshwater lake environment at Gale crater was profound scientifically, but also was the moment that I knew that our team had delivered what we promised to NASA.”

Basically, by scaling Mount Sharp and examining the layers that were deposited over the course of billions of years, Curiosity is able to examine a living geological record of how the planet has evolved since then. Essentially, the lower layers of the mountain are believed to have been deposited 3.5 billion years ago when the Gale Crater was still a lakebed, as evidenced by the fact that they are rich in clay minerals.

The upper layers, meanwhile, are believed to have been deposited over the ensuing millions of years, during which time the lake in the Gale Crater appears to have grown, shrunk, disappeared and then reappeared. Basically, by scaling the mountain and obtaining samples, Curiosity will be able to illustrate how Mars underwent the transition from being a warmer, wetter place to a frozen and dry one.

Image taken of drill sample obtained at the ‘Lubango’ outcrop target on Sol 1320, Apr. 23, 2016. Lubango is located in the Stimson unit on the lower slopes of Mount Sharp inside Gale Crater. Credit: NASA/JPL/MSSS/Ken Kremer/kenkremer.com/Marco Di Lorenzo

As Vasavada explained, this exploration is also key to answering a number of foundational questions about the search for life beyond Earth:

“Curiosity established that Mars was once a suitable home for life; it had liquid water, key chemical building blocks, and energy sources required by life in the lake and groundwater environment within Gale crater. Curiosity also has detected organic molecules in ancient rocks, in spite of all the degradation that could have occurred in three billion years. While Curiosity cannot detect life itself, knowing that Mars can preserve organic molecules bodes well for missions that will explore ancient rocks, looking for signs of past life.”

At this juncture, its not clear how much longer Curiosity will last. Considering that it has already lasted over twice as long as originally intended, it is possible the rover will remain in operation for years to come. However, unlike the Opportunity rover – who’s mission was intended to last for 90 days, but has remained in operation for 5121 days (4984 sols) – Curiosity has a shelf life.

Whereas Opportunity is powered by solar cells, Curiosity is dependent on its Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). Eventually, this slow-fission reactor will exhaust its supply of nuclear fuel and the rover will be forced to come to a halt. And considering how the rover has been put through its paces in the past 5 years, there’s also the chance that it will suffer a mechanical failure.

But in the meantime, there’s plenty of work to be done and lots of opportunities for vital research. As Vasavada put it:

“Curiosity won’t last forever, but in the years we have left, I hope we can complete our traverse through the lowermost strata on Mount Sharp. We’re well over halfway through. There are changes in the composition of the rocks ahead that might tell us how the climate of Mars changed over time, perhaps ending the era of habitability. Every day on Mars still counts, perhaps even more than before. Now every new discovery adds a piece to a puzzle that’s more than halfway done; it reveals more given all the other pieces already around it.”

And be sure to check out this retrospective of the Curiosity rover’s mission, courtesy of NASA:

Further Reading: Forbes, NASA

January 26, 2018 by Evan Gough

NASA’s Insight Lander Spreads Its Solar Wings. It’ll Fly To Mars In May, 2018

The Insight lander responds to commands to spread its solar arrays during a January 23, 2018 test at the Lockheed Martin clean room in Littleton, Colorado. Image: Lockheed Martin Space

May 2018 is the launch window for NASA’s next mission to Mars, the InSight Lander. InSight is the next member of what could be called a fleet of human vehicles destined for Mars. But rather than working on the question of Martian habitability or suitability for life, InSight will try to understand the deeper structure of Mars.

InSight stands for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport. InSight will be the first robotic explorer to visit Mars and study the red planet’s deep interior. The work InSight does should answer questions about the formation of Mars, and those answers may apply to the history of the other rocky planets in the Solar System. The lander, (InSight is not a rover) will also measure meteorite impacts and tectonic activity happening on Mars currently.

This video helps explain why Mars is a good candidate to answer questions about how all our rocky planets formed, not just Mars itself.

InSight was conceived as part of NASA’s Discovery Program, which are missions focused on important questions all related to the “content, origin, and evolution of the solar system and the potential for life elsewhere”, according to NASA. Understanding how our Solar System and its planets formed is a key part of the Discovery Program, and is the question InSight was built to answer.

This artist's illustration of InSight on a photo background of Mars shows the lander fully deployed. The solar arrays are open, and in the foreground two of its instruments are shown. On the left is the SEIS instrument, and on the right is the HP3 probe. Image: NASA/Lockheed Martin — This artist’s illustration of InSight on a photo background of Mars shows the lander fully deployed. The solar arrays are open, and in the foreground two of its instruments are shown. On the left is the SEIS instrument, and on the right is the HP3 probe. Image: NASA/Lockheed Martin

To do its work, InSight will deploy three instruments: SEIS, HP³, and RISE.

SEIS

This is InSight’s seismic instrument, designed to take the Martian pulse. It stands for Seismic Experiment for Internal Structure.

SEIS sits patiently under its dome, which protects it from Martian wind and thermal effects, and waits for something to happen. What’s it waiting for? For seismic waves caused by Marsquakes, meteorite impacts, or by the churning of magma deep in the Martian interior. These waves will help scientists understand the nature of the material that first formed Mars and the other rocky planets.

HP³

HP³ is InSight’s heat probe. It stands for Heat Flow and Physical Properties Probe. Upon deployment on the Martian surface, HP³ will burrow 5 meters (16 ft.) into Mars. No other instrument has ever pierced Mars this deeply. Once there, it will measure the heat flowing deeply within Mars.

In this image, the Heat Flow and Physical Properties Probe is shown inserted into Mars. Image: NASA

Scientists hope that the heat measured by HP³ will help them understand whether or not Mars formed from the same material that Earth and the Moon formed from. It should also help them understand how Mars evolved after it was formed.

RISE

RISE stands for Rotation and Interior Structure Experiment. RISE will measure the Martian wobble as it orbits the Sun, by precisely tracking InSight’s position on the surface. This will tell scientists a lot about the deep inner core of Mars. The idea is to determine the depth at which the Martian core is solid. It will also tell us which elements are present in the core. Basically, RISE will tell us how Mars responds to the Sun’s gravity as it orbits the Sun. RISE consists of two antennae on top of InSight.

InSight will land at Elysium Planitia which is a flat and smooth plain just north of the Martian equator. This is considered a perfect location or InSight to study the Martian interior. The landing sight is not far from where Curiosity landed at Gale Crater in 2012.

InSight will land at Elysium Planitia, just north of the Martian equator. Image: NASA/JPL-CalTech

InSight will be launched to Mars from Vandenberg Air Force Base in California by an Atlas V-401 rocket. The trip to Mars will take about 6 months. Once on the Martian surface, InSight’s mission will have a duration of about 728 Earth days, or just over 1 Martian year.

InSight won’t be launching alone. The Atlas that launches the lander will also launch another NASA technology experiment. MarCO, or Mars Cube One, is two suitcase-size CubeSats that will travel to Mars behind InSight. Once in orbit around Mars, their job is to relay InSight data as the lander enters the Martian atmosphere and lands. This will be the first time that miniaturized CubeSat technology will be tested at another planet.

One of the MarCO Cubesats that will be launched with InSight. This will be the first time that CubeSat technology will be tested at another planet. Image: NASA/JPL-CalTech

If the MarCO experiment is successful, it could be a new way of relaying mission data to Earth. MarCO will relay news of a successful landing, or of any problems, much sooner. However, the success of the InSight lander is not dependent on a successful MarCO experiment.

January 19, 2018 by Evan Gough

Researchers Develop a New Low Cost/Low Weight Method of Searching for Life on Mars

Study co-author I. Altshuler sampling permafrost terrain near the McGill Arctic research station, Canadian high Arctic. Image: Dr. Jacqueline Goordial

Researchers at Canada’s McGill University have shown for the first time how existing technology could be used to directly detect life on Mars and other planets. The team conducted tests in Canada’s high arctic, which is a close analog to Martian conditions. They showed how low-weight, low-cost, low-energy instruments could detect and sequence alien micro-organisms. They presented their results in the journal Frontiers in Microbiology.

Getting samples back to a lab to test is a time consuming process here on Earth. Add in the difficulty of returning samples from Mars, or from Ganymede or other worlds in our Solar System, and the search for life looks like a daunting task. But the search for life elsewhere in our Solar System is a major goal of today’s space science. The team at McGill wanted to show that, conceptually at least, samples could be tested, sequenced, and grown in-situ at Mars or other locations. And it looks like they’ve succeeded.

Recent and current missions to Mars have studied the suitability of Mars for life. But they don’t have the ability to look for life itself. The last time a Mars mission was designed to directly search for life was in the 1970’s, when NASA’s Viking 1 and 2 missions landed on the surface. No life was detected, but decades later people still debate the results of those missions.

The Viking 2 lander captured this image of itself on the Martian surface. The Viking Landers were the last missions to directly look for life on Mars. By NASA - NASA website; description,[1] high resolution image.[2], Public Domain, https://commons.wikimedia.org/w/index.php?curid=17624 — The Viking 2 lander captured this image of itself on the Martian surface. The Viking Landers were the last missions to directly look for life on Mars. By NASA – NASA website; description,[1] high resolution image.[2], Public Domain, https://commons.wikimedia.org/w/index.php?curid=17624

But Mars is heating up, figuratively speaking, and the sophistication of missions to Mars keeps growing. With crewed missions to Mars a likely reality in the not-too-distant future, the team at McGill is looking ahead to develop tools to search for life there. And they focused on miniature, economical, low-energy technology. Much of the current technology is too large or demanding to be useful on missions to Mars, or to places like Enceladus or Europa, both future destinations in the Search for Life.

“To date, these instruments remain high mass, large in size, and have high energy requirements. Such instruments are entirely unsuited for missions to locations such as Europa or Enceladus for which lander packages are likely to be tightly constrained.”

The team of researchers from McGill, which includes Professor Lyle Whyte and Dr. Jacqueline Goordial, have developed what they are calling the ‘Life Detection Platform (LDP).’ The platform is modular, so that different instruments can be swapped out depending on mission requirements, or as better instruments are developed. As it stands, the Life Detection Platform can culture microorganisms from soil samples, assess microbial activity, and sequence DNA and RNA.

There are already instruments available that can do what the LDP can do, but they’re bulky and require more energy to operate. They aren’t suitable for missions to far-flung destinations like Enceladus or Europa, where sub-surface oceans might harbour life. As the authors say in their study, “To date, these instruments remain high mass, large in size, and have high energy requirements. Such instruments are entirely unsuited for missions to locations such as Europa or Enceladus for which lander packages are likely to be tightly constrained.”

A key part of the system is a miniaturized, portable DNA sequencer called the Oxford Nanopore MiniON. The team of researchers behind this study were able to show for the first time that the MiniON can examine samples in extreme and remote environments. They also showed that when combined with other instruments it can detect active microbial life. The researches succeeded in isolatinh microbial extremophiles, detecting microbial activity, and sequencing the DNA. Very impressive indeed.

This image shows the instruments tested in the Life Detection Platform. Image: J. Goordial et. al.

These are early days for the Life Detection Platform. The system required hands-on operation in these tests. But it does show proof of concept, an important stage in any technological development. “Humans were required to carry out much of the experimentation in this study, while life detection missions on other planets will need to be robotic,” says Dr Goordial.

“Humans were required to carry out much of the experimentation in this study, while life detection missions on other planets will need to be robotic.” – Dr. J. Goordial

The system as it stands now is useful here on Earth. The same things that allow it to search for and sequence microorganisms on other worlds make it suitable for the same task here on Earth. “The types of analyses performed by our platform are typically carried out in the laboratory, after shipping samples back from the field,” says Dr. Goordial. This makes the system desirable for studying epidemics in remote areas, or in rapidly changing conditions where transporting samples to distant labs can be problematic.

These are very exciting times in the Search for Life in our Solar System. If, or when, we discover microbial life on Mars, Europa, Enceladus, or some other world, it will likely be done robotically, using equipment similar to the LDP.

January 13, 2018January 13, 2018 by Matt Williams

Huge Sheets of Ice Found Hidden Just Beneath the Surface of Mars

A cross-section of underground ice is exposed at the steep slope that appears bright blue in this enhanced-color view from the HiRISE camera on NASA's Mars Reconnaissance Orbiter. Credits: NASA/JPL-Caltech/UA/USGS

Its an established fact that Mars was once a warmer and wetter place, with liquid water covering much of its surface. But between 4.2 and 3.7 billion years ago, the planet lost its atmosphere, which caused most of its surface water to disappear. Today, much of that water remains hidden beneath the surface in the form of water ice, which is largely restricted to the polar regions.

In recent years, scientists have also learned of ice deposits that exist in the equatorial regions of Mars, though it was unlcear how deep they ran. But according to a new study led by the U.S. Geological Survey, erosion on the surface of Mars has revealed abundant deposits of water ice. In addition to representing a major research opportunity, these deposits could serve as a source of water for Martian settlements, should they ever be built.

The study, titled “Exposed subsurface ice sheets in the Martian mid-latitudes“, recently appeared in Science. The study was led by Colin M. Dundas, a researcher with the U.S. Geological Survey, and included members from the Lunar and Planetary Laboratory (LPL) at the University of Arizona, Johns Hopkins University, the Georgia Institute of Technology, the Planetary Science Institute, and the Institute for Geophysics at the University of Texas at Austin.

*Artists concept of the Mars Reconnaisance Orbiter (MRO). Credit: NASA/JPL*

For the sake of their study, the team consulted data obtained by the High Resolution Imaging Science Experiment (HiRISE) aboard the Mars Reconnaissance Orbiter (MRO). This data revealed eight locations in the mid-latitude region of Mars where steep slopes created by erosion exposed substantial quantities of sub-surface ice. These deposits could extend as deep as 100 meters (328 feet) or more.

The fractures and steep angles indicate that the ice is cohesive and strong. As Dundas explained in a recent NASA press statement:

“There is shallow ground ice under roughly a third of the Martian surface, which records the recent history of Mars. What we’ve seen here are cross-sections through the ice that give us a 3-D view with more detail than ever before.”

These ice deposits, which are exposed in cross-section as relatively pure water ice, were likely deposited as snow long ago. They have since become capped by a layer of ice-cemented rock and dust that is between one to two meters (3.28 to 6.56 ft) thick. The eight sites they observed were found in both the northern and southern hemispheres of Mars, at latitudes from about 55° to 58°, which accounts for the majority of the surface.

It would be no exaggeration to say that this is a huge find, and presents major opportunities for scientific research on Mars. In addition to affecting modern geomorphology, this ice is also a preserved record of Mars’ climate history. Much like how the Curiosity rover is currently delving into Mars’ past by examining sedimentary deposits in the Gale Crater, future missions could drill into this ice to obtain other geological records for comparison.

*At this pit on Mars, the steep slope at the northern edge (toward the top of the image) exposes a cross-section of a thick sheet of underground water ice. Credits: NASA/JPL-Caltech/UA/USGS*

These ice deposits were previously detected by the Mars Odyssey orbiter (using spectrometers) and ground-penetrated radar aboard the MRO and the ESA’s Mars Express orbiter. NASA also sent the Phoenix lander to Mars in 2008 to confirm the findings made by the Mars Odyssey orbiter, which resulted in it finding and analyzing buried water ice located at 68° north latitude.

However, the eight scarps that were detected in the MRO data directly exposed this subsurface ice for the first time. As Shane Byrne, the University of Arizona Lunar and Planetary Laboratory and a co-author on the study, indicated:

“The discovery reported today gives us surprising windows where we can see right into these thick underground sheets of ice. It’s like having one of those ant farms where you can see through the glass on the side to learn about what’s usually hidden beneath the ground.”

These studies would also help resolve a mystery about how Mars’ climate changes over time. Today, Earth and Mars have similarly-tiled axes, with Mars’ axis tilted at 25.19° compared to Earth’s 23.439°. However, this has changed considerably over the course of eons, and scientists have wondered how increases and decreases could result in seasonal changes.

Artist’s impression of glaciers that may have existed on the surface of Mars in the past. Credit: NASA/Caltech/JPL/UTA/UA/MSSS/ESA/DLR Eric M. De Jong, Ali Safaeinili, Jason Craig, Mike Stetson, Koji Kuramura, John W. Holt

Basically, during periods where Mars’ tilt was greater, climate conditions may have favored a buildup of ice in the middle-latitudes. Based on banding and color variations, Dundas and his colleagues have suggested that layers in the eight observed regions were deposited in different proportions and with varying amounts of dust based on varying climate conditions.

As Leslie Tamppari, the MRO Deputy Project Scientist at NASA’s Jet Propulsion Laboratory, said:

“If you had a mission at one of these sites, sampling the layers going down the scarp, you could get a detailed climate history of Mars. It’s part of the whole story of what happens to water on Mars over time: Where does it go? When does ice accumulate? When does it recede?”

The presence of water ice in multiple locations throughout the mid-latitudes on Mars is also tremendous news for those who want to see permanent bases constructed on Mars someday. With abundant water ice just a few meters below the surface, and which is periodically exposed by erosion, it would be easily accessible. It would also mean bases need not be built in polar areas in order to have access to a source of water.

This research was made possible thanks to the coordinated use of multiple instruments on multiple Mars orbiters. It also benefited from the fact that these missions have been studying Mars for extended periods of time. The MRO has been observing Mars for 11 years now, while the Mars Odyssey probe has been doing so for 16. What they have managed to reveal in that time has provided all kinds of opportunities for future missions to the surface.

Further Reading: NASA, Science

December 13, 2017 by Matt Williams

NASA’s Opportunity Rover Withstands Another Harsh Winter on Mars

Artist's impression of the Opportunity Rover, part of NASA's Mars Exploration Program. NASA/JPL-Caltech

When the Opportunity rover landed on Mars on January 25th, 2004, its mission was only meant to last for about 90 Earth days. But the little rover that could has exceeded all expectations by remaining in operation (as of the writing of this article) for a total of 13 years and 231 days and traveled a total of about 50 km (28 mi). Basically, Opportunity has continued to remain mobile and gather scientific data 50 times longer than its designated lifespan.

And according to a recent announcement from NASA’s Mars Exploration Program (MEP), the rover managed to survive yet another winter on Mars. Having endured the its eight Martian winter in a row, and with its solar panels in encouragingly clean condition, the rover will be in good shape for the coming dust-storm season. It also means the rover will live to see its 14th anniversary, which will take place on January 25th, 2018.

On Mars, a single year lasts the equivalent of 686.971 Earth days (or 1.88 Earth years). And since Mars’ axis is inclined 25.19° to its orbital plane (compared to Earth’s axial tilt of just over 23°), Mars also experiences seasons. However, these tend to last about twice as long as the seasons on Earth. And of course, the seasons on Mars’ are also much colder, with temperatures averaging about -63 °C (-82°F).

Enhanced-color view of ground sloping downward to the right in “Perseverance Valley”, taken by the Pancam on the Opportunity rover in October of 2017. Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ

As Jennifer Herman, the power subsystem operations team lead for Opportunity at NASA’s Jet Propulsion Laboratory, recalled in a NASA MEP press statement:

“I didn’t start working on this project until about Sol 300, and I was told not to get too settled in because Spirit and Opportunity probably wouldn’t make it through that first Martian winter. Now, Opportunity has made it through the worst part of its eighth Martian winter.”

At present, both the Opportunity and Spirit rover are in Mars’ southern hemisphere. Here, the Sun appears in the northern sky during the fall and winter, so the rovers need to tilt their solar-arrays northward. Back in 2004, the Spirit rover had lost the use of two of its wheels, and could therefore not maneuver out of a sand trap it had become stuck in. As such, it was unable to tilt itself northward and did not survive its fourth Martian winter (in 2009).

However, Opportunity’s current position – Perseverance Valley, a fluid-carved region on the inner slope at the edge of the Endeavour Crater – meant that it was well-positioned to keep working through late fall and early winter this year. This was ensured by the stops the rover made at energy-favorable locations, where it would inspect local rocks, examine the valley’s shape and image the surrounding area, all the while absorbing ample energy from the Sun.

Image of the floor of Endeavour Crater, taken by NASA’s Mars Exploration Rover Opportunity on Nov. 11th, 2017, about a week before Opportunity’s eighth Martian winter solstice. Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ

Five months ago, the rover entered the top of the valley, which runs eastward down the inner slope of the Endurance Crater’s western rim. Since that time, Opportunity has been conducting stops between drives at north-facing sites, which are situated along the southern edge of the channel. The rover team calls the sites “lily pads”, since these places are spots that the rover need to hop across during its mission.

This is necessary, given that Opportunity does not rely on a radioisotope thermoelectric generator like Curiosity does. While winter conditions affect the use of electrical heaters and batteries on both rovers, Opportunity is different in that it’s activities are more subject to seasonal change. Whereas Curiosity will simply allocate less energy to performing tasks in the winter, Opportunity needs to pick its routes to ensure it stays powered up.

During some of its previous winters, the Opportunity rover was not as well-situated as it currently is. During its fifth winter (2011-2012) the rover spent 19 weeks at one spot because no other places that allowed for a northward-facing tilt were available within driving distance. On the other hand, its first winter (2004-2005) was spent in the southern half of the Endurance Crater, where all grounds are favorable since they face north.

As the person who is chiefly responsible for advising other mission scientists on how much energy Opportunity has available on each Martian day (sol) for conducting activities like driving and observing – a task she performs for Curiosity as well – Herman understand the relationship between power usage and the seasons all too well. “Relying on solar energy for Opportunity keeps us constantly aware of the season on Mars and the terrain that the rover is on, more than for Curiosity,” she said.

*A self-portrait of the Opportunity rover shortly after dust cleared its solar panels in March 2014. Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.*

Another factor which can influence Opportunity‘s power supply is how much dust is in the sky and how much of it gets onto the rover’s solar arrays. This is highly-dependent on prevailing wind conditions, which can both stir up dust storms and clear away dust deposits on the rover – basically, they are a real mixed blessing! During autumn and winter in the southern-hemisphere, the skies are generally clear where Opportunity operates.

Spring and summer is when the storms are most common in Mars’ southern hemisphere, though they don’t happen every year. The latest example took place in 2007, which led to a severe reduction in the amount of sunlight (and hence, solar energy) Spirit and Opportunity were able to receive. This required both rovers to enact emergency protocols and reduce the amount of operations and communications they conducted.

The amount of dust on the rover’s solar arrays going into autumn can also vary from year to year. This year, the array was dustier than in all but one of the previous Martian autumns it experienced. Luckily, as Herman explained, things worked out for the rover:

“We were worried that the dust accumulation this winter would be similar to some of the worst winters we’ve had, and that we might come out of the winter with a very dusty array, but we’ve had some recent dust cleaning that was nice to see. Now I’m more optimistic. If Opportunity’s solar arrays keep getting cleaned as they have recently, she’ll be in a good position to survive a major dust storm. It’s been more than 10 Earth years since the last one and we need to be vigilant.”

*Image of the Opportunity rover’s front wheel, taken on June 9th, 2004, inside the Endurance Crater. Credit: NASA/JPL/Cornell*

In the coming months, the Opportunity team hopes to investigate how the Perseverance Valley was cut into the rim of the Endeavor crater. As Matt Golombek, an Opportunity Project Scientist at JPL, related:

“We have not been seeing anything screamingly diagnostic, in the valley itself, about how much water was involved in the flow. We may get good diagnostic clues from the deposits at the bottom of the valley, but we don’t want to be there yet, because that’s level ground with no more lily pads.”

With its eighth winter finished and Opportunity still in good working order, we can expect the tenacious rover to keep turning up interesting finds on Mars. These include clues about Mars’ warmer, wetter past, which likely included a standing body of water in the Endeavor crater. And assuming conditions are favorable in the coming year, we can expect that Opportunity will continue to push the boundaries of both science and its own endurance!

Further Reading: NASA

November 22, 2017November 30, 2017 by Matt Williams

These Streaks on Mars Could be Flowing Sand, not Water

These dark, narrow, 100 meter-long streaks called recurring slope lineae flowing downhill on Mars are inferred to have been formed by contemporary flowing water. However, a new study by planetary scientists indicates that these may actually be the result of dry flows. Credits: NASA/JPL/University of Arizona

When robotic missions first began to land on the surface of Mars in the 1970s, they revealed a harsh, cold and desiccated landscape. This effectively put an end generations of speculation about “Martian canals” and the possibility of life on Mars. But as our efforts to explore the Red Planet have continued, scientists have found ample evidence that the planet once had flowing water on its surface.

In addition, scientists have been encouraged by the appearance of Recurring Slope Lineae (RSL), which were believed to be signs of seasonal water flows. Unfortunately, a new study by researchers from the U.S. Geological Survey indicates that these features may be the result of dry, granular flows. These findings are another indication that the environment could be too dry for microorganisms to survive.

The study, titled “Granular Flows at Recurring Slope Lineae on Mars Indicate a Limited Role for Liquid Water“, recently appeared in the scientific journal Nature Geoscience. Led by Dr. Colin Dundas, of the US Geological Survey’s Astrogeology Science Center, the team also included members from the Lunar and Planetary Laboratory (LPL) at the University of Arizona and Durham University.

This inner slope of a Martian crater has several of the seasonal dark streaks called “recurrent slope lineae,” or RSL, which were caputred by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter. Credits: NASA/JPL-Caltech/UA/USGS

For the sake of their study, the team consulted data from the High Resolution Image Science Experiment (HiRISE) camera aboard the NASA Mars Reconnaissance Orbiter (MRO). This same instrument was responsible for the 2011 discovery of RSL, which were found in the middle latitudes of Mars’ southern hemisphere. These features were also observed to appear on Martian slopes during late spring through summer and then fade away in winter.

The seasonal nature of these flows was seen as a strong indication that they were the result of flowing salt-water, which was indicated by the detection of hydrated salt at the sites. However, after re-examining the HiRISE data, Dundas and his team concluded that RSLs only occur on slopes that are steep enough for dry grains to descend – in much the same way that they would on the faces of active dunes.

As Dundas explained in a recent NASA press release:

“We’ve thought of RSL as possible liquid water flows, but the slopes are more like what we expect for dry sand. This new understanding of RSL supports other evidence that shows that Mars today is very dry.”

Using pairs of images from HiRISE, Dundas and his colleagues constructed a series of 3-D models of slope steepness. These models incorporated 151 RSL features identified by the MRO at 10 different sites. In almost all cases, they found that the RSL were restricted to slopes that were steeper than 27° and each flow ended on a slope that matched the patterns seen in slumping dry sand dunes on Mars and Earth.

*Dark, narrow streaks flowing downhill on Mars at sites like the Horowitz Crater are inferred to be due to seasonal flows of water. Credit: NASA/JPL-Caltech/Univ. of Arizona*

Basically, sand flows end where a steep angle gives way to a less-steep “angle of repose”, whereas liquid water flows are known to extend along less steep slopes. As Alfred McEwen, HiRISE’s Principal Investigator at the University of Arizona and a co-author of the study, indicated, “The RSL don’t flow onto shallower slopes, and the lengths of these are so closely correlated with the dynamic angle of repose, it can’t be a coincidence.”

These observations is something of a letdown, since the presence of liquid water in Mars’ equatorial region was seen as a possible indication of microbial life. However, compared to seasonal brine flows, the present of granular flows is a far better fit with what is known of Mars’ modern environment. Given that Mars’ atmosphere is very thin and cold, it was difficult to ascertain how liquid water could survive on its surface.

Nevertheless, these latest findings do not resolve all of the mystery surrounding RSLs. For example, there remains the question of how exactly these numerous flows begin and gradually grow, not to mention their seasonal appearance and the way they rapidly fade when inactive. On top of that, there is the matter of hydrated salts, which have been confirmed to contain traces of water.

To this, the authors of the study offer some possible explanations. For example, they indicate that salts can become hydrated by pulling water vapor from the atmosphere, which might explain why patches along the slopes experience changes in color. They also suggest that seasonal changes in hydration might result in some trigger mechanism for RSL grainflows, where water is absorbed and release, causing the slope to collapse.

*NASA’s Mars Reconnaissance Orbiter investigating Martian water cycle. Credit: NASA/JPL/Corby Waste*

If atmospheric water vapor is a trigger, then it raises another important question – i.e. why do RSLs appear on some slopes and not others? As Alfred McEwen – HiRISE’s Principal Investigator and a co-author on the study – explained, this could indicate that RSLs on Mars and the mechanisms behind their formation may not be entirely similar to what we see here on Earth.

“RSL probably form by some mechanism that is unique to the environment of Mars,” he said, “so they represent an opportunity to learn about how Mars behaves, which is important for future surface exploration.” Rich Zurek, the MRO Project Scientist of NASA’s Jet Propulsion Laboratory, agrees. As he explained,

“Full understanding of RSL is likely to depend upon on-site investigation of these features. While the new report suggests that RSL are not wet enough to favor microbial life, it is likely that on-site investigation of these sites will still require special procedures to guard against introducing microbes from Earth, at least until they are definitively characterized. In particular, a full explanation of how these enigmatic features darken and fade still eludes us. Remote sensing at different times of day could provide important clues.”

In the coming years, NASA plans to carry out the exploration of several sites on the Martian surface using the Mars 2020 rover, which includes a planned sample-return mission. These samples, after being collected and stored by the rover, are expected to be retrieved by a crewed mission mounted sometime in the 2030s, and then returned to Earth for analysis.

The days when we are finally able to study the Mars’ modern environment up close are fast approaching, and is expected to reveal some pretty Earth-shattering things!

Further Reading: NASA

November 10, 2017 by Matt Williams

Life on Mars can Survive for Millions of Years Even Right Near the Surface

Researchers from Lomonosov MSU, Faculty of Soil Science, have studied the resistance microorganisms have against gamma radiation in very low temperatures. Credit: YONHAP/EPA

Mars is not exactly a friendly place for life as we know it. While temperatures at the equator can reach as high as a balmy 35 °C (95 °F) in the summer at midday, the average temperature on the surface is -63 °C (-82 °F), and can reach as low as -143 °C (-226 °F) during winter in the polar regions. Its atmospheric pressure is about one-half of one percent of Earth’s, and the surface is exposed to a considerable amount of radiation.

Until now, no one was certain if microorganisms could survive in this extreme environment. But thanks to a new study by a team of researchers from the Lomonosov Moscow State University (LMSU), we may now be able to place constraints on what kinds of conditions microorganisms can withstand. This study could therefore have significant implications in the hunt for life elsewhere in the Solar System, and maybe even beyond!

The study, titled “100 kGy gamma-affected microbial communities within the ancient Arctic permafrost under simulated Martian conditions“, recently appeared in the scientific journal Extremophiles. The research team, which was led by Vladimir S. Cheptsov of LMSU, included members from the Russian Academy of Sciences, St. Petersburg State Polytechnical University, the Kurchatov Institute and Ural Federal University.

*Image taken by the Viking 1 orbiter in June 1976, showing Mars thin atmosphere and dusty, red surface. Credits: NASA/Viking 1*

For the sake of their study, the research team hypothesized that temperature and pressure conditions would not be the mitigating factors, but rather radiation. As such, they conducted tests where microbial communities contained within simulated Martian regolith were then irradiated. The simulated regolith consisted of sedimentary rocks that contained permafrost, which were then subjected to low temperature and low pressure conditions.

As Vladimir S. Cheptsov, a post-graduate student at the Lomonosov MSU Department of Soil Biology and a co-author on the paper, explained in a LMSU press statement:

“We have studied the joint impact of a number of physical factors (gamma radiation, low pressure, low temperature) on the microbial communities within ancient Arctic permafrost. We also studied a unique nature-made object—the ancient permafrost that has not melted for about 2 million years. In a nutshell, we have conducted a simulation experiment that covered the conditions of cryo-conservation in Martian regolith. It is also important that in this paper, we studied the effect of high doses (100 kGy) of gamma radiation on prokaryotes’ vitality, while in previous studies no living prokaryotes were ever found after doses higher than 80 kGy.”

To simulate Martian conditions, the team used an original constant climate chamber, which maintained the low temperature and atmospheric pressure. They then exposed the microorganisms to varying levels of gamma radiation. What they found was that the microbial communities showed high resistance to the temperature and pressure conditions in the simulated Martian environment.

Spirit Embedded in Soft Soil on Mars — *Image of Martian soils, where the Spirit mission embedded itself. Credit: NASA/JPL*

However, after they began irradiating the microbes, they noticed several differences between the irradiated sample and the control sample. Whereas the total count of prokaryotic cells and the number of metabolically active bacterial cells remained consistent with control levels, the number of irradiated bacteria decreased by two orders of magnitude while the number of metabolically active cells of archaea also decreased threefold.

The team also noticed that within the exposed sample of permafrost, there was a high biodiversity of bacteria, and this bacteria underwent a significant structural change after it was irradiated. For instance, populations of actinobacteria like Arthrobacter – a common genus found in soil – were not present in the control samples, but became predominant in the bacterial communities that were exposed.

In short, these results indicated that microorganisms on Mars are more survivable than previously thought. In addition to being able to survive the cold temperatures and low atmospheric pressure, they are also capable of surviving the kinds of radiation conditions that are common on the surface. As Cheptsov explained:

“The results of the study indicate the possibility of prolonged cryo-conservation of viable microorganisms in the Martian regolith. The intensity of ionizing radiation on the surface of Mars is 0.05-0.076 Gy/year and decreases with depth. Taking into account the intensity of radiation in the Mars regolith, the data obtained makes it possible to assume that hypothetical Mars ecosystems could be conserved in an anabiotic state in the surface layer of regolith (protected from UV rays) for at least 1.3 million years, at a depth of two meters for no less than 3.3 million years, and at a depth of five meters for at least 20 million years. The data obtained can also be applied to assess the possibility of detecting viable microorganisms on other objects of the solar system and within small bodies in outer space.”

*Future missions could determine the presence of past life on Mars by looking for signs of extreme bacteria. Credit: NASA.*

This study was significant for multiple reasons. On the one hand, the authors were able to prove for the first time that prokaryote bacteria can survive radiation does in excess of 80 kGy – something which was previously thought to be impossible. They also demonstrated that despite its tough conditions, microorganisms could still be alive on Mars today, preserved in its permafrost and soil.

The study also demonstrates the importance of considering both extraterrestrial and cosmic factors when considering where and under what conditions living organisms can survive. Last, but not least, this study has done something no previous study has, which is define the limits of radiation resistance for microorganisms on Mars – specifically within regolith and at various depths.

This information will be invaluable for future missions to Mars and other locations in the Solar System, and perhaps even with the study of exoplanets. Knowing the kind of conditions in which life will thrive will help us to determine where to look for signs of it. And when preparing missions to other words, it will also let scientists know what locations to avoid so that contamination of indigenous ecosystems can be prevented.

Further Reading: Lomonsonov Moscow State University, Extremophiles