In 2021, a NASA rover will touch down on Mars in search of signs of life, past or present. It will investigate the surface of the red planet and collect samples from areas that seem particularly promising. But traces of life on Mars—if they exist—aren’t going to be apparent to the naked eye: Obviously there’s no remains of mammoths or goldfish or snails. Any record of life on Mars would likely take the form of organic compounds, which have already been identified up there but aren’t definitive, or actual fossils of microorganisms. Such fossils exist here on Earth, but they’re very tricky to spot—even in places we know they’ll be. The best strategy for finding these miniscule traces, according to a group of Scandinavian scientists, is to study the denizens of the deep sea. This team now plans to create an atlas of fossilized microbes from Earth’s oceans—an extraterrestrial field guide of sorts—to help the rover and its human partners identify definitive proof of life on Mars, according to their recent article in Frontiers in Earth Science.
Europe has been in orbit around Mars for more than 15 years and is almost a year away from launching its first rover mission, but ambitions are already running high to go one step further: returning a sample from the Red Planet.
In 2016, ESA and Roscomos launched the 3.7 tonne ExoMars Trace Gas Orbiter (TGO), the heaviest spacecraft operating at Mars today. Dedicated to analysing the planet’s atmosphere in greater detail than ever, it is making a census of the gases present and to find out if any have a biological or geological origin. The spacecraft is also providing a global map of water distribution in terms of water-ice or water-hydrated minerals in the shallow sub-surface of Mars.
TGO is also a key provider of data-relay services to NASA’s Insight lander and Curiosity rover on the surface of Mars. It will be the primary communications relay for the second ExoMars mission, which comprises a rover and surface science platform. It is on track for launching in July 2020 and will arrive at Mars in March 2021. TGO is already getting ready for the new arrival: next month it will make adjustments to its orbit to ensure it will be in the correct position to support the entry, descent and landing of the descent module.
After driving off the surface platform and studying its surrounds, the rover, named Rosalind Franklin, will locate scientifically interesting sites to examine. It will retrieve samples from 2 m below the ground, where they are protected from the harsh radiation that bombards the surface, for analysis in its highly advanced onboard laboratory to search for evidence of life.
When most people imagine hunting for fossils, they probably think of finding dinosaur bones laid down in layers of rock. But the vast majority of life – and therefore fossils – across Earth’s history has been microorganisms. These tiny lifeforms, either plants, animals or fungi, can be smaller than the width of a human hair. But with the right tools, the fossilized records of these tiny creatures reveal insights into the history of a planet. Even planets that aren’t Earth.
A group of Swedish scientists led by Magnus Ivarsson point out in research published May 1 in Frontiers in Earth Science that instruments already planned for upcoming space missions like the Mars 2020 rover could detect tiny fossils on Mars, if they exist. But Mars 2020 can’t analyze every rock it encounters in detail, so the researchers propose a few ways to determine the best places to look on the Red Planet.
In May 2018, Opportunity had been doing science on Mars since 2004, and there was no reason to think that the plucky rover wouldn’t carry on. Then, a dust storm hit that completely obscured the planet from view. After fine dust coated Opportunity’s solar panels, the rover apparently lost power and was declared dead by NASA in February 2019. Now, scientists think similar storms may have also delivered a coup de grace to water on Mars, stripping it from its surface for good.
At one point, Mars had a thick atmosphere and up to 20 percent of its surface was covered by liquid water, scientists figure. Around 4 billion years ago, however, Mars lost its magnetic field and with little to protect it from destructive solar winds, the red planet lost much of its atmosphere.
That left water on the surface vulnerable, and according to new observations from the ExoMars Trace Gas Orbiter (TGO), dust storms may have helped finish off the oceans and lakes. While water particles in the atmosphere normally linger at around 12 miles (20 km) in altitude, TGO noticed that the dust storms that killed Opportunity lifted H20 molecules up to 50 miles (80 km) above the ground.
Long ago on Mars, water carved deep riverbeds into the planet’s surface—but we still don’t know what kind of weather fed them. Scientists aren’t sure, because their understanding of the Martian climate billions of years ago remains incomplete.
A new study by University of Chicago scientists catalogued these rivers to conclude that significant river runoff persisted on Mars later into its history than previously thought. According to the study, published March 27 in Science Advances, the runoff was intense—rivers on Mars were wider than those on Earth today—and occurred at hundreds of locations on the red planet.
But it’s a puzzle why ancient Mars had liquid water. Mars has an extremely thin atmosphere today, and early in the planet’s history, it was also only receiving a third of the sunlight of present-day Earth, which shouldn’t be enough heat to maintain liquid water. “Indeed, even on ancient Mars, when it was wet enough for rivers some of the time, the rest of the data looks like Mars was extremely cold and dry most of the time,” Kite said.
Seeking a better understanding of Martian precipitation, Kite and his colleagues analyzed photographs and elevation models for more than 200 ancient Martian riverbeds spanning over a billion years. These riverbeds are a rich source of clues about the water running through them and the climate that produced it. For example, the width and steepness of the riverbeds and the size of the gravel tell scientists about the force of the water flow, and the quantity of the gravel constrains the volume of water coming through.
Their analysis shows clear evidence for persistent, strong runoff that occurred well into the last stage of the wet climate, Kite said.
Mars Express has revealed the first geological evidence of a system of ancient interconnected lakes that once lay deep beneath the Red Planet’s surface, five of which may contain minerals crucial to life.
Mars appears to be an arid world, but its surface shows compelling signs that large amounts of water once existed across the planet. We see features that would have needed water to form – branching flow channels and valleys, for example – and just last year Mars Express detected a pool of liquid water beneath the planet’s south pole.
A new study now reveals the extent of underground water on ancient Mars that was previously only predicted by models.
“Early Mars was a watery world, but as the planet’s climate changed this water retreated below the surface to form pools and ‘groundwater’,” says lead author Francesco Salese of Utrecht University, the Netherlands.
“We traced this water in our study, as its scale and role is a matter of debate, and we found the first geological evidence of a planet-wide groundwater system on Mars.”
NASA’s Martian rover Opportunity breathed its last digital gasp this week. What was a busy scurrying robot picking over and investigating the Martian landscape is now a slowly decaying pile of metal and circuitry. That is to say, Opportunity has entered my world, the world of abandoned things that is archaeology.
Humans have been dreaming about Martian archaeology for well over a century now. When the Italian Astronomer Giovanni Schiaparelli described seeing canali on the surface of the red planet in 1877, many in the English-speaking world began to speculate that Schiaparelli was referring to artificially constructed canals. Percival Lowell became the largest champion of this interpretation. In his 1895 book “Mars,” Lowell claimed that the canals of Mars had been built by a desperate alien race seeking to salvage what water they could from the planet’s melting ice caps.
Yet all along this journey, the Martian landscape has become populated by actual human-made objects. Fourteen separate missions from four different space agencies have littered the surface of the Mars with not only landers and rovers, but heat shields, parachutes, and an untold number of broken bits. As an archaeologist, I love broken bits.
The things that people make and leave behind tell a different story then written history. A physical examination of landing sites on Mars would reveal critical details about why some landers arrived safely while others crashed to never be heard from again. Even the crashed landers tell a story of human triumph and ingenuity. One day, an astronaut will walk up to the original Viking 1 lander and marvel at the accomplishments of their ancestors. The material heritage we are currently scattering across the Martian surface will stand for centuries to come as a symbol of what we as human beings can do.
The UK-assembled rover that will be sent to Mars in 2020 will bear the name of DNA pioneer Rosalind Franklin.
The honour follows a public call for suggestions that drew nearly 36,000 responses from right across Europe.
Astronaut Tim Peake unveiled the name at the Airbus factory in Stevenage where the robot is being put together.
The six-wheeled vehicle will be equipped with instruments and a drill to search for evidence of past or present life on the Red Planet.
Giving the rover a name associated with a molecule fundamental to biology seems therefore to be wholly appropriate.
Rosalind Franklin played an integral role in the discovery of the structure of deoxyribonucleic acid.
It was her X-ray images that allowed James Watson and Francis Crick to decipher its double-helix shape.
Franklin’s early death from ovarian cancer in 1958, aged just 37, meant she never received the recognition given to her male peers.
The attachment to the European Space Agency (Esa) rover will now see her name travel beyond Earth.
“In the last year of Rosalind’s life, I remember visiting her in hospital on the day when she was excited by the news of the [Soviet Sputnik satellite] – the very beginning of space exploration,” Franklin’s sister, Jenifer Glynn, said on Thursday.
“She could never have imagined that over 60 years later there would be a rover sent to Mars bearing her name, but somehow that makes this project even more special.”
Astrobiologist Alberto Fairén of Cornell University and the Center of Astrobiology in Madrid, Spain, asks a provocative question in a paper published recently in EOS: How will our exploration of Mars change the Red Planet?
The term Anthropocene has been widely used for the current period in Earth’s geological history, in which human actions have had enough impact on the planet that we see a clear distinction from the previous period, the Holocene. The geological signatures of that transition include a variety of features such as the extinction of many animal and plant species, an increase of carbon dioxide in the atmosphere (resulting in global warming), deposition of plastic in sediments, movements of soil from mining, and the construction of highways, dams, and residential areas.
The Anthropocene as a geological epoch is not formally recognized, but has been widely used to indicate a period where humans majorly affect planet Earth, beginning sometime in the mid-20th century. Fairén suggests that the same nomenclature should be used for Mars, starting with the first human mission slated for the mid-21st century. The thinking is that with the arrival of the first humans, we will inevitably leave topographic changes such as buildings and excavations, especially when utilizing natural resources on Mars as currently envisioned by NASA. To some extent we already have made changes, considering all our abandoned or crashed spacecraft on the planet and the tracks from our rovers. But once we see the first astronaut bootprints in the Martian sands, the impact will be so significant that, according to Fairén, we ought to speak no longer of the Late Amazonian period on Mars, but of the Mars Anthropocene. Earth and Mars will then have a shared geological epoch.
One hundred and ninety-eight meteorites from Mars have been discovered on Earth as of Sep., 2017. Hypervelocity impacts on Mars have been a widely accepted mechanism that launches Martian rocks into the space. Petrographic analyses of the Martian meteorites have shown that they suffer relatively low peak pressure ranging from 30 to 50 GPa during impact ejection events. In contrast, shock physics tells us that a stronger shock compression higher than 50 GPa is required to accelerate materials up to the escape velocity of Mars (5 km/s). This contradiction between petrology and shock physics was the outstanding problem regarding the Martian meteorites’ launch.
he new discovery of late-stage acceleration has a wide range of implications not only for the Martian meteorites’ launch, but also for material exchange amongst planetary bodies (See Figure 1). Since microbes may survive the relatively weak shock compression, the late-stage acceleration could provide us with new insight into (Litho-)Panspermia. The researchers are planning to do a series of hypervelocity impact experiments to validate the numerically discovered new mechanism using a two-stage light gas gun installed at the Planetary Exploration Research Center, Chiba Institute of Technology, Japan.