This year was supposed to be another landmark one for Mars exploration with the launch of the European Space Agency (ESA)’s robot rover to the red planet. But now, the mission has to be postponed as a result of the war in Ukraine and heavy sanctions on Russia, which owns the spaceport in Kazakhstan from which the rover was supposed to be launched.
The rover, known as Rosalind Franklin, named after the British chemist and DNA pioneer, is part of the ExoMars program, which also includes the Trace Gas Orbiter launched in 2016. Like NASA’s Curiosity and Perseverance rovers, the goal of the mission is to search for signs of past life on Mars, which is believed to have been a rich water world billions of years ago.
In order to achieve its goal, the ExoMars mission will do things differently than its American counterparts. The deepest anyone has dug on Mars is only six centimeters, and that is a problem if your goal is to look for signs of life, present or past. Scientists believe it is very unlikely to find such evidence in the top meter of Martian soil as millions of years of exposure to cosmic radiation, ultraviolet light, and powerfully oxidizing perchlorates likely destroyed any organic biosignature a long time ago.
“The recipe we have with ExoMars is we’re going to drill below all that crap,” to a depth of two meters, ExoMars project scientist Jorge Vago tells Inverse. “Our hypothesis is that if you go to the right place and drill deep enough, you may be able to get access to well preserved organic material from 4 billion years ago, when conditions on the surface of Mars were more like what we had on infant Earth.”
The astrobiology lab on six wheels is a joint venture between the ESA and Roscosmos, the Russian space agency. While Rosalind Franklin is operated by the ESA, Russia’s contribution includes the Kazachok lander vehicle, meant to land and safely release the rover on Mars’s Oxia Planum, a region thought to have once been the coastline of a very large northern hemisphere ocean. Additionally, Russia developed several important science instruments for the mission, as well as offered the launch platform. Only the International Space Station is more significant in terms of cooperation between the ESA and Russia.
Originally planned for 2020, the launch of the mission was postponed to 20 September 2022 from the Baikonur cosmodrome in Kazakhstan. But considering the dire situation in Ukraine and the heavy sanctions imposed by the United States and its European allies, the mission has now been postponed indefinitely.
“We are fully implementing sanctions imposed on Russia by our Member States,” the ESA announced in a press statement. “Regarding the ExoMars program continuation, the sanctions and the wider context make a launch in 2022 very unlikely.”
“We are giving absolute priority to taking proper decisions, not only for the sake of our workforce involved in the programmes, but in full respect of our European values, which have always fundamentally shaped our approach to international cooperation.”
The announcement comes on the heels of Roscosmos’s decision over the week to suspend flights of its Soyuz rockets from the Kourou spaceport in French Guiana, as a retaliation for the western sanctions. Roscosmos has even gone as far as putting into question the viability of the International Space Station, where it has been a founding partner since the station’s first modules were launched in 1998. That’s despite Washington having been clear that its stiff sanctions targeting the Russian economy and tech sector will continue to allow U.S.-Russian civil space cooperation.
It’s too early to say what might happen next but it’s likely that Roscosmos cannot be counted on for ExoMars moving forward. This means that the rover must be launched using a different partner and a new landing platform needs to be developed, which could amount to at least another two years of delay. That’s when the next favorable launch window is available — every two years Mars and Earth’s orbits align allowing for a much shorter journey between the two planets.
As the crisis in Ukraine drags on, it’s saddening to see how the war not only disrupts people’s lives across the world and causes unspeakable suffering, but also how its effects extend well beyond our borders — even to another planet.
It’d be fantastic to visit another planet and be greeted by friendly little green aliens. It really would, but that’s just projecting popular culture. Alas, when we’ll finally find the first extraterrestrial life forms — if such a milestone ever occurs — in all likelihood, these will be microbes. Not just any boring-looking, amoeba-shaped microbes though. According to scientists at the University of Illinois at Urbana-Champaign, alien microbes or their fossils for that matter could look like fettuccini or capellini.
That’s how some hot-spring-loving microbes are shaped here on Earth, and if you ever visited Yellowstone National Park, you may have seen signs of them. The nation’s largest national park is dotted by hot geothermal water flowing from the ground, which is rich in minerals. These minerals precipitate, forming fibrous structures of calcium carbonate called travertine.
When Bruce Fouke, a geobiologist at the University of Illinois at Urbana-Champaign, visited Mammoth Hot Springs in the park, he found that the travertine looked like, well, pasta. Focusing on the head of the mineral spring, where the water is particularly hot (65 to 72 degrees Celsius) and more acidic, Fouke’s team sampled filamentous microbe mats. These pasta strands owe their shape to the rushing nature of the hot water spring, which forces organisms to cling to one another in order to survive, whereas in calmer water microbes settle in unconsolidated, slimy mats. Each thread consists of trillions of microbes, which thrive where 99.99% of all other life forms would have perished.
After taking a sample to the lab, the researchers found that the pasta mats are formed by Sulfurihydrogenibium yellowstonense, or “sulfuri” for short. True to their name, these bacteria break down sulfur compounds, producing hydrogen sulfide gas in the process and energy for themselves in order to survive. Proteins on the surface of these microbes react with the mineral-rich waters, encouraging the growth of calcium carbonate crystals and speeding up the formation of travertine a billion times faster than in other environments. Where there’s pasta-shaped travertine, you’ll find sulfuri, and vice-versa.
“They form tightly wound cables that wave like a flag that is fixed on one end. These Sulfuri cables look amazingly like fettuccine pasta, while further downstream they look more like capellini pasta,” Fouke said.
Sulfuri represents one of the oldest types of life on Earth, having evolved more than 2.5 billion years ago when Earth was a hellish planet with barely any oxygen in its atmosphere. And although any alien microbes living in hot springs will undoubtedly be of a different species, they would probably look and behave a lot like Earth’s sulfuri given the limited number of ways carbon-based life can work in such extreme environments.
Should a rover encounter pasta-shaped travertine on another planet like Mars, these rock formations could be treated as fossils. The unique morphology of the travertine would make it quite easy to spot too.
“This should be an easy form of fossilized life for a rover to detect on other planets,” Fouke added.
“If we see the deposition of this kind of extensive filamentous rock on other planets, we would know it’s a fingerprint of life. It’s big and it’s unique. No other rocks look like this. It would be definitive evidence of the presence of alien microbes,” the scientist added.
So far, we’ve yet to find filamentous travertine in Mars, but the now-defunct Spirit rover did find some odd cauliflower-shaped silica formations in the Gustav Crater, a region thought to have once harbored ancient Martian hot springs. These rocks resemble those shaped by microbes on Earth, actually at Yellowstone National Park where the silica contains the fossilized remains of microorganisms. Unfortunately, Spirit became unoperational before it had the chance to investigate further. Elsewhere at Gale Crater, the Curiosity rover found sedimentary rocks that seem to have signs of possible microbial mats. However, Curiosity doesn’t have the necessary hardware to make a proper analysis.
Perhaps the new Perseverance rover, which arrived on Mars in 2021 at Jezero Crater, will be luckier. Hopefully, it will be treated to a nice dish of fettuccine pasta by some Martian chef.
Curiosity has been wandering the Martian landscape for over ten years, and it’s made some groundbreaking discoveries in the meantime. Some of these, astronomers were kind of expecting. Others came as a surprise — and others are simply hard to understand.
For instance, rocks of all sizes (from tiny pebbles to big boulders) seem to have this weird, purple coating, and it’s not clear what the coating is. Ann Ollila, a geochemist at Los Alamos National Laboratory who presented an early analysis of the coatings at a recent conference of the American Geophysical Union (AGU), says she has no good answer as to what the coating may be.
The purple color, and the fact that Curiosity has discovered traces of hydrogen around these purple coatings, hints at the involvement of water in the process. Curiosity’s Mastcam-Z images also suggest the coatings may contain types of iron oxide. In particular, NASA researchers are thinking about hematite — an iron oxide mineral that’s relatively common on Earth.
“Variations in color of the rocks hint at the diversity of their composition on lower Mount Sharp. The purple tone of the foreground rocks has been seen in other rocks where Curiosity’s Chemical and Mineralogy (CheMin) instrument has detected hematite,” or a type of iron-oxide mineral, NASA officials said in a statement a few years back, referring to the image above. “Winds and windblown sand in this part of Curiosity’s traverse and in this season tend to keep rocks relatively free of dust, which otherwise can cloak rocks’ color.”
A more recent analysis of these purple patches notes that they are are “typically observed in less dusty areas of most rock surfaces”, and linked them with “both fine-grained crystalline hematite and poorly crystalline iron oxides.”
But the problem is, hematite is grey, black, or rust-red on Earth — so something else may be at play on Mars, which could be good news for Mars’ potential habitability.
For starters, variations in these minerals hint at an active, dynamic geological system. These dynamic systems tend to produce complex chemical structures, and the more complex the chemical structure, the better it is for habitability. We already know there are plenty of clays on Mars, clays that may have interacted with water in the Martian past. These coatings could tell the story of what happened in the planet’s geological past, and maybe even offer hints of what’s happening now.
Researchers took a closer look at the coatings, using the rover’s SuperCam. The instrument can examine rocks and soils with a camera and spectrometers, looking for compounds related to past life on Mars. But it can also shoot a laser to vaporize a small bit of the coating. A microphone then picks up the sound from this laser and analyzing the ‘clack’ sound the laser makes when it hits the rock, researchers can infer some of the rock properties.
It’s a challenging process, further hindered by the winds on Mars that affect the microphone, but so far, analyses suggest that the coating is chemically different from the underlying rocks. The findings also confirm the idea that the coatings may contain types of iron oxide, but they may also contain other things that Curiosity’s instruments haven’t picked up yet.
There’s also a chance that these coatings could be linked to microbial activity. While this is very speculative at this point, such coatings on Earth have been found to be linked with microbes, and it could be that microbes once hid in the tiny cracks on Martian rocks. Some research has even suggested that these coatings could protect microbes from the solar activity they are exposed to on Mars — though again, this is speculative at this point.
But there’s another conundrum: Perseverance’s route, where it’s seeing all the purple-coated rocks, doesn’t pass through lake sediments, but rather through rocks that were formed through the cooling of magma. It is possible that the rocks were brought, through geological processes, from a different location — but Mars also doesn’t have plate tectonics, so it’s not clear exactly what type of process would move the rocks around.
The Curiosity team is planning several experiments that could shed more light on this puzzling coating, but the best way to sort it out is to bring samples back to Earth for analysis. It’s not clear if the coatings would survive the trip to Earth, but researchers are hopeful.
In the meantime, Curiosity’s journey and experiments will continue. Who knows what it will come across next?
Putting a satellite into Mars orbit has never been easy. For the information and data they need to gather, probes must obtain a specific low-altitude orbit. To achieve this orbit, satellites utilize a technique called Aerobraking which brushes the craft against the top of a planetary atmosphere. To attain the maximum drag, the orbiter lowers the craft’s altitude with a little help from its solar panels. However, this procedure takes fuel and lots of time to complete, generally up to six months.
Now though, engineers at the University of Illinois Urbana-Champaign are improving upon the process to save both time, energy and money.
“The trip out to Mars takes somewhere between six to nine months,” said Zach Putnam, an aerospace engineering professor at the university. “We can’t really change that, but we think we can shorten the time it takes to aerobrake to a low-altitude orbit. And the propellant onboard we save can be used to do other things like keep the spacecraft alive longer.”
Engineers have created a real-time algorithm that rotates a satellite’s solar panels which can control how much drag is generated on the spacecraft. The algorithm includes control modes to limit heat rate or heat load — or both — while attempting to take advantage of energy reduction. The process can then be used to steer the craft during atmospheric passes in order to control heating and energy depletion. This process allows the satellite to fly much closer to operational constraints and aerobrake much faster.
“Being able to steer the satellite during each atmospheric pass enables us to ensure we don’t over temperature the solar panels while flying much closer to the thermal limit,” Putnam said. “This is a big improvement. Instead of aerobraking for three to six months, it might only take a couple of weeks.”
Aerobraking consists of three phases: Walk-In, Main Phase and Walk-Out.
During the Walk-In phase, engineers direct the spacecraft to lower the periapsis (the closest point to Mars in its orbit) one orbit at a time, moving the spacecraft from its Mars orbit insertion altitude to its aerobraking altitude. This phase is utilized as a calibration period to understand atmospheric densities and the way which the orbiter performs in and out of aerobraking. This generally lasts about a week or five orbits of the Red Planet.
The Main Phase is the longest and can last around five and a half months. Once the satellite reaches its operational altitude (where the desired atmospheric densities were found), the main stage of aerobraking commences. The orbiter is commanded to perform large-scale decreases in its orbit. If the altitude got too low, the craft would be in danger of overheating. If the altitude gets too high, aerobraking finishes too late. Therefore, small propulsive maneuvers are occasionally performed to keep the satellite within a specified “corridor” by raising or lowering its periapsis altitude.
The Walk-Out Phase is the shortest phase at about five days. Here the orbiter to increases its periapsis, causing the orbit to shrink more leisurely. When the apoapsis (the farthest away from Mars the spacecraft reached in its orbit) reduces to 280 miles (450 kilometers), the periapsis is raised out of the atmosphere and aerobraking is finished.
Putnam believes the new process will transform the way future Mars orbiters operate.
“This software would greatly reduce our reliance on ground stations,” he said. “If we can automate it onboard and only have to check in with the spacecraft once a week, that would really bring costs down. And, it could be done by many satellites at the same time.”
The study was published in the Journal of Guidance, Control and Dynamics.
The Red Planet has its own version of the Grand Canyon, only at a much grander scale. The largest canyon system on Mars, known as Valles Marineris, is at least ten times longer, five times deeper, and 20 times wider than the Grand Canyon in Arizona. Although it is now drier and more barren than any desert on Earth, Valles Marineris’s subsurface may be unusually rich in water, and it’s found not all that deep either, making it highly accessible for potential Martian astronauts.
According to geologists and geophysicists who analyzed data gathered by the Trace Gas Orbiter between May 2018 and February 2021, the subsurface material under an area about the size of the Netherlands could be made up of as much as 40% water. The data was recorded by the Mars orbiting spacecraft’s FREND instrument, or Fine Resolution Epithermal Neutron Detector, which is able to map hydrogen emissions in the topmost layer of Martian soil (about one meter, or 3.28 feet).
The instrument actually detects neutrons emitted when galactic cosmic rays strike the Martian soil. These neutrons represent a marker of hydrogen and, by extension, water. Drier soils emit more neutrons than wetter ones, for instance. This observation technique allowed the researchers to map water content under Valles Marineris with unprecedentedly high resolution while revealing water features that couldn’t be spotted before.
Writing in the journal Icarus, the researchers affiliated with the European Space Agency (ESA) reported that as much as 40% of the near-surface material in this region, which measures around 41,000 km2, appears to be water. More than likely the water exists in the form of ice. Some of the water may also be attached to minerals within the soil.
“With TGO we can look down to one meter below this dusty layer and see what’s really going on below Mars’ surface – and, crucially, locate water-rich ‘oases’ that couldn’t be detected with previous instruments,” says Igor Mitrofanov of the Space Research Institute of the Russian Academy of Sciences in Moscow and lead author of the new study.
Billions of years ago, Mars used to be a water world with large oceans and fast-flowing rivers dotting its landscape. Most of that water has dried up and escaped into space after the planet lost its magnetic field, thinning its atmosphere to a volume less than 1% of Earth’s.
But not all of this water has been lost. Large swaths of water ice have been identified in the planet’s polar regions. Still, while finding water on Mars is, by now, not any news in itself, the wet cache found under Valles Marineris is remarkable due to its geography. The huge canyon system is found just south of the Martian equator, where temperatures aren’t as cold as at the poles to support water ice on the surface. However, the temperatures are mild enough to sustain a potential Martian colony. Indeed, the region around Valles Marineris has been previously identified as a potential landing spot for a manned mission.
According to researchers, the water beneath Valles Marineris can be compared to Earth’s permafrost regions, where water ice can be found under dry soil. More research, however, is required in order to establish the special mix of conditions that have accommodated water in the region despite the high temperatures near the equator.
“This finding is an amazing first step, but we need more observations to know for sure what form of water we’re dealing with,” said study coauthor Håkan Svedhem, a former project scientist for the orbiter, in a statement.”The finding demonstrates the unrivaled abilities of TGO’s instruments in enabling us to ‘see’ below Mars’ surface — and reveals a large, not-too-deep, easily exploitable reservoir of water in this region of Mars.”
Some of the most amazing scientific discoveries are actually happy accidents. Back in 2017, the otherwise sturdy Curiosity rover went through one of its first crises when its drill bit suddenly malfunctioned. Without this drill, much of Curiosity’s mission of finding signs of habitability, past or present, would have been seriously jeopardized. Luckily, NASA engineers repaired the system malfunction remotely, but a new study has reported what the rover found in that particular sample that Curiosity took exactly when the drill broke down.
Curiosity analyzes powdered samples drilled from rocks in order to measure the chemical fingerprints present in these various minerals and soils. This data helps scientists to determine the composition of Martian soil and rock, but also their history, especially as it relates to their past interaction with water. Gale Crater, where the rover was deployed, is believed to have once hosted a large body of water billions of years ago.
Typically, the sampling technique involves placing the dirt sample into an empty, dry cup. But when the drill bit broke down, the very last sample before the malfunction was placed into a cup containing a chemical cocktail made of reagents. The rover arrived on Mars equipped with nine of these pre-filled cups.
This type of sampling, known as a wet sampling experiment, caused a chemical reaction that allowed NASA researchers to identify organic molecules previously never observed on Mars.
“This experiment was definitely successful,” Maëva Millan, a postdoctoral fellow at NASA’s Goddard Spaceflight Center and lead author of the new study, tells Inverse. “While we haven’t found what we were looking for, biosignatures, we showed that this technique is really promising.”
In their new study published this week in the journal NatureAstronomy, NASA scientists have reported for the first time the presence of ammonia and benzoic acid on Mars. That was surprising since such molecules were thought to be nonviable due to the radiation presence on the Martian surface. Previously, other organic molecules identified by NASA included thiophenes, benzene, toluene, and some small molecules made of carbon chains.
Organic molecules are the building blocks of life. However, ammonia and benzoic acid aren’t exactly biosignatures — but the precursor molecules could be. That’s why scientists at NASA are now focused on finding these molecules that may indicate past habitability on the red planet. The 2022 ExoMars mission led by the European Space Agency (ESA) may provide this opportunity, as well as the Perseverance rover whose samples will be returned to Earth between 2028 and 2030.
“Once we have found that, we can say where they originated from,” Millan says. “As of now, with all the molecules that we have found on Mars, we have made the hypothesis that they could come from geological processes.”
New research is investigating the role bacteria could play in future efforts to grow food on planets such as Mars. While such an approach has been shown to boost the growth of clover plants, more work needs to be done to determine exactly how to proceed with off-world farming.
Nitrogen is a key nutrient for plant growth, one which typically acts as a bottleneck here on Earth. Nitrogen itself cannot be directly assimilated by plants or animals, despite it being available in the atmosphere. Nature has found a workaround to this issue through the formation of symbiotic relationships between the roots of plants and nitrogen-fixing bacteria. These supply essential compounds to the roots that, in turn, feed the bacterial nodules.
Martian soil, or regolith, also lacks essential nutrients, including nitrogen compounds, which would severely limit our ability to grow food in space. In a bid to understand whether we could enrich alien dirt with the aid of Earth-born bacteria, a new study reports on efforts to grow clover in simulated regolith.
Clover for good luck
“Nodule forming bacteria Sinorhizobium meliloti has been shown to nodulate in Martian regolith, significantly enhancing the growth of clover (Melilotus officinalis) in a greenhouse assay. This work increases our understanding of how plant and microbe interactions will help aid efforts to terraform regolith on Mars,” the study reads.
For the study, the team planted clover plants in a man-made regolith substitute that closely resembles that found on Mars. Some of the plants were inoculated with nitrogen-fixing, nodule-forming bacteria, while the others were left to fend for themselves. Sinorhizobium meliloti is a common bacterium on Earth that naturally forms symbiotic relationships with clover plants. Previous research has shown that clover plants can grow in regolith substitutes, the authors explain, but didn’t explore the effects of nitrogen-fixing bacteria on their growth rate.
One of the key findings of the study was that inoculated plants experienced a significantly higher rate of growth than the controls. They recorded 75% more growth in the roots and shoots of these plants compared to clovers which didn’t have access to the bacteria.
Although the bacteria had a positive effect on the plants themselves, the team also reports not seeing any increase in ammonium (NH4) levels in the regolith. In other words, the soil itself did not become enriched in any meaningful way in key nitrogen compounds that other plants could tap into. Furthermore, the symbiotic relationship between bacteria and clovers planted in regolith showed some functional differences compared to those of clovers planted in potting soil.
This suggests that even with the benefit of nitrogen-fixing bacteria on their side, crops sown in alien soils might still develop at different rates to crops on Earth.
All in all, however, the research proves that there is a case to be made for growing crops on alien worlds. Although there are still many unknowns regarding this topic, and even considering a lower yield rate, it remains an attractive proposition. Shuttling materials to outer space remains extremely expensive. It’s also a very long trip to Mars. Both of these factors make it impractical to rely on food transports from Earth to feed a potential colony.
But we are making strides towards offering space explorers greater autonomy. For example, we’re exploring new ways to produce building materials from astronauts’ own bodies and waste. We’re also working on ways to obtain water from regolith.
We’re likely not ready to grow crops in space, however, and the authors note that more research is needed to understand exactly how such a process should be handled. Chief among these, they want to expand their research to other types of crops, and to address possible issues of plant toxicity in regolith.
The paper “Soil fertility interactions with Sinorhizobium-legume symbiosis in a simulated Martian regolith; effects on nitrogen content and plant health” has been published in the journal PLOS ONE.
Whether or not Mars is still volcanically active is still a matter of debate. What’s certain is true is that, in the past, the red planet was very volcanically active — and then some. Most of Mars’ volcanism occurred between three and four billion years ago, spawning giant geological features such as the 25-km-tall (16-mile) Olympus Mons, the highest mountain in the solar system.
Recently, NASA found evidence that a region of northern Mars called Arabia Terra experienced thousands of so-called “super-eruptions” over a 500-million-year period.
These kinds of eruptions, the most violent volcanic explosions known to science, were no joke. Relatively small volcanic eruptions on Earth are known to release carbon dioxide, sulfur dioxide, and other aerosols that can block sunlight and significantly reduce surface temperature.
The same happened on Mars, but only on a more massive scale. One single super eruption could have blasted out the equivalent of 400 million Olympic-size swimming pools worth of molten rock and gas.
“Each one of these eruptions would have had a significant climate impact — maybe the released gas made the atmosphere thicker or blocked the Sun and made the atmosphere colder,” said Patrick Whelley, a geologist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who led the Arabia Terra analysis. “Modelers of the Martian climate will have some work to do to try to understand the impact of the volcanoes.”
Mars’ surface is littered with craters. Anywhere you go, you’re bound to find at least one within a couple of hundred kilometers. These craters are formed by one of two processes: impact (with a comet, meteorite, or asteroid), or by volcanic eruptions.
When very large volcanoes reach the end of their lifetimes, they collapse into a giant hole called a caldera, some of which can be dozens of kilometers wide. It was several of these calderas identified across Arabia Terra that prompted NASA scientists to look closer.
Unlike impact craters, which tend to be perfectly round, calderas bear signs of collapse such as deeper floors and benches of rock near the walls. However, there ought to be many other calderas in the region that haven’t been spared by the passage of time in the same way as these obviously visible formations.
The researchers decided to look for signs of ancient calderas by looking for ash “because you can’t hide that evidence,” Whelley said. So they used data from NASA’s Mars Reconnaissance Orbiter (MRO) to look for signs of ash across Arabia Terra, finding many well-preserved layers of the material.
When the researchers crunched the numbers, they figured that it would’ve taken thousands of supervolcanic eruptions to deposit the amount of ash registered in the data.
On Earth, volcanoes capable of super-eruptions are distributed around the globe, along with other volcano types. The last such cataclysmic eruption occurred 76,000 years ago in Sumatra, Indonesia. In contrast, Arabia Terra is littered with only one type of volcano, a mysterious oddity that scientists can’t yet explain. Arabia Terra is the only place on Mars where we found evidence of explosive volcanoes.
In the meantime, researchers are still busy combing through the MRO data to better understand the geological process that shaped the solar system’s planets and moons.
“People are going to read our paper and go, ‘How? How could Mars do that? How can such a tiny planet melt enough rock to power thousands of super eruptions in one location?’” said Jacob Richardson, a geologist at NASA Goddard. “I hope these questions bring about a lot of other research.”
It was only meant to be a proof of concept; a test of what could be possible. Ingenuity has proven itself to be more than worthy, and NASA researchers have now rewarded its success with more work — such is the life of a Mars explorer.
Ingenuity hitched a ride to Mars attached to the belly of the Perseverance rover. NASA envisions that one day, rover/helicopter duos could be the norm of planetary exploration, but that day seemed far away. Now, it doesn’t seem far at all.
The problem with flying a helicopter on a planet like Mars is that its atmosphere (if you can call it that) is 100 times thinner than what we have on Earth, which makes flying way more difficult. When Ingenuity powered itself up over the Martian soil, it was a real Wright brothers moment — the first man-made vehicle to fly on a planet other than the Earth.
If Ingenuity had crashed on its second flight, it probably wouldn’t even have been all that bad. After all, its main goal was to fly up to five times, at altitudes no higher than 5 meters, for 90 seconds each. Now, after 12 flights in which the helicopter rose to a height of 12 m (39 ft), achieved all its objectives and gathered all the information it was meant to, NASA has finally extended its mission indefinitely.
“Everything is working so well,” said Josh Ravich, the head of Ingenuity’s mechanical engineering team. “We’re doing better on the surface than we had expected.”
Ingenuity has been now switched to a new operations demonstration phase, showcasing how rovers and aerial explorers can work together. After a series of roundtrip flights, Ingenuity has been embarking on a series of one-way trips, accompanying the Perseverance rover as it explores Mars, surveying and taking photos from above. Overall, the helicopter has flown 2.83 km (1.76 mi) and shows no signs of stopping soon.
Surveying Mars from above is more than just a show of strength — it’s already paying dividends. For instance, flights taken by Ingenuity during its 12th flight showed that one region on Mars (dubbed South Seitha) was not as interesting as researchers were hoping for. As a result, the rover may choose a different path and focus on exploring other regions.
Now, the Ingenuity team plans to make one flight every 2-3 weeks, as long as conditions remain favorable. So far, everything went according to plan, but at some point in October, all operations will need to be shut down, as Mars passes behind the Sun, blocking communications. If the helicopter is able to withstand this period and is responsive after it’s turned back on, the mission will resume.
Since the mission went so well, NASA is already looking at bigger helicopters carrying a bigger payload for future missions. No doubt, Ingenuity was amazing on its own — but it has also paved the way for some amazing science in the future.
Meanwhile, Perseverance is also carrying its own weight. After a botched first try, the rover managed to extract a rock sample from Mars, a sample that is set to return to Earth for analysis by 2031.
All in all, these are great times for Mars exploration. Who knows, maybe a space race is slowly starting to kick off.
The second time’s the charm, at least for NASA’s Perseverance rover on Mars. The car-sized robot was apparently able to retrieve a rock sample on Mars on the second attempt, drilling the core of a rock dubbed “Rochette.” However, celebrations will need to wait just a bit, as more information is still needed before the sampling can be declared a success, mission engineers say.
If at first you don’t succeed
The rover had already made a sampling attempt on August 5, but the rock it drilled into was too soft and crumbled to dust that didn’t make it to the sampling tube. If Perseverance was successful this time with its drilling attempt, it would be the first-ever rock section collected on another planet that is set to return to Earth. Quite something!
Perseverance arrived in Mars back in February, with the mission of collecting more than two dozen cores over the next year or so. If everything goes according to plan, the samples will be brought back to Earth as in 2031 by a joint United States and European effort. For now, NASA is now waiting for better pictures from Mars before declaring the core drilling an actual success.
“The project got its first cored rock under its belt, and that’s a phenomenal accomplishment,” Jennifer Trosper, project manager at NASA, said in a statement. “The team determined a location, and selected and cored a viable and scientifically valuable rock. We did what we came to do. We remain encouraged that there is sample in this tube.”
Following the first attempt, the scientists at NASA piloted Perseverance to a new area so to look for a different kind of rock to sample. The rover was driven to the west, where the team found a larger rock that seemed less likely to disintegrate by deploying tools on it. Still, several tests were done before going for the actual drilling procedure.
Perseverance took photos of the rock and did an abrasion test to check if the rock, Rochette, was durable enough for the sample. Among many tools, the rover has a drill that can spin and hammer into the rock. The abrasion test was successful, so the scientists gave the green light. Perseverance then used the drill and extracted the core sample.
A careful drilling
Images from the rover’s cameras show that the rock made it to the tube this time without crumbling into dust. Nothing seemed to get stuck in the mouth of the tube, which is good, as it has to be closed and stored in order to be safely delivered. But the researchers were worried about one photo that showed darkness in the tube, which could mean that the rock was shaken out of the tube.
Still, NASA remains optimistic and believes this is just due to bad lighting, and the sample is safely stored. That’s why they’ve decided to take more photos under diverse lighting conditions and then make the official announcement on whether the rock core was collected or not. The announcement could be done as early as tomorrow, with the space community currently on the edge of their chairs.
Perseverance has 43 sampling tubes, and NASA hopes to fill at least 20 of them before calling an end to the mission. While the rover has been chilling on Mars in February, it took its time before doing science work as it was first helping with the first flights of NASA’s Mars helicopter Ingenuity, designed to show that aerial exploration is possible on Mars.
Zhurong is China’s first rover to land on another planet. Part of the Tianwen-1 mission to Mars conducted by the China National Space Administration (CNSA), the rover has been on the red planet for over three months. To celebrate the achievement, China released a set of striking photos from the Martian surface.
So far, the rover has traveled just over 1 kilometer and has already exceeded its initial objectives. It was only expected to operate on Mars for three months, so everything it accomplishes from now on is a bonus.
The rover’s main objective is to look at the Martian geology and atmosphere, surveying the minerals and rocks it encounters, as well as the soil and ice (should it come across it). The rover is also equipped to sample the Martian atmosphere.
The rover is surveying a geologic area called Utopia Planitia, the largest known impact basin in the solar system, with an estimated diameter of 3300 km. This is also where the Viking 2 lander touched down and started exploring in 1976.
However, the orbiter will have to pause its exploration in a couple of weeks, when Mars and the Earth will be on opposite sides of the Sun (almost in a straight line). During this period, called the Mars solar conjunction, communications with the rover will be interrupted.
But this is unlikely to end the rover’s mission, as everything so far seems to be going smoothly. In addition, the Tianwen-1 Mars mission also consists of an orbiter that will continue to circle Mars. The orbiter has already been in place for over 400 days.
China’s ambitions to establish itself as an authentic space power seem more serious than ever. After launching the first module on its new space station and launching astronauts on the module, China is focusing much of its space efforts on the moon but also has its eyes on other targets, such as Mars.
For those of us eager to learn more about the solar system, this new space race looks like a treat.
At the same time the Zhurong rover is carrying out its mission, the American Perseverance rover is also exploring Mars, with much more ambitious objectives. For starters, Perseverance is expected to last at least a few years on Mars, and at over a ton, it dwarfs Zhurong’s 240 kilograms (529 lbs). Perseverance is also equipped with more and more diverse sensors, capable of studying Mars in more detail. It is also accompanied by the Ingenuity helicopter, the first man-made object to take flight on a foreign planet. Ingenuity has also covered more than 2.67 km (1.66 mi) in flight, accompanying Perseverance, which covered 1.97 km (1.22 mi).
There’s still a big gap between the US and the Chinese space programs, but with unprecedented spending and a lot to prove to the world, China’s eager to close in on that gap.
There are very good reasons why Mars is such a desolate, barren landscape. With no thick atmosphere nor a magnetic field, the Red Planet’s surface is bombarded daily by radiation up to 900 times higher than seen on Earth. However, some places are sheltered. New research has found that cave entrances are shielded from the harmful radiation that normally hits Mars. This may make them ideal as both sites for future settlements and robotic missions meant to scour for signs of alien life.
Despite amazing advances in space exploration in the last decade, if we’re going to take the idea of settling Mars sometime during this century seriously, there are many challenges that need to be overcome. That’s unless we’re content with one-way suicide missions.
There’s no shortage of environmental hazards out to kill any astronaut bold enough to dare set foot on Mars. For one, the planet only has 0.7% of Earth’s sea-level pressure, meaning any human on Mars must wear a full pressure suit or stay barricaded inside a pressure-controlled chamber, otherwise oxygen wouldn’t flow through the bloodstream and the body could swell and bleed out.
Then there’s the issue of radiation. Mars is farther away from the Sun than Earth, receiving roughly 60% of the power per square meter seen on a similar site on Earth. But since Mars doesn’t have a magnetic field to deflect energetic particles, coupled with the paper-thin atmosphere, its surface is exposed to much higher levels of radiation than Earth. Furthermore, besides regular exposure to cosmic rays and solar wind, it receives occasional, lethal radiation blasts due to strong solar flares.
Measurements performed by the Mars Odyssey probe suggest that ongoing radiation levels on Mars are at least 2.5 times higher than what astronauts experience on the International Space Station. That’s about 22 millirads per day, which works out to 8000 millirads (8 rads) per year. For comparison, the people in the U.S. are exposed to roughly 0.62 rads/year on average.
Any attempt to colonize the Red Planet will require measures to ensure radiation exposure is kept to a minimum. Some of the proposed ideas thus far involve habitats built directly into the ground or even above-ground habitats using inflatable modules encased in ceramics.
But a better idea may be to take advantage of the natural shelters already in place. Mars is dotted with deep pits, caves, and lava tube structures across its surface. According to a new study performed by researchers led by Daniel Viúdez-Moreiras at Spain’s National Institute for Aerospace Technology, many of these caverns could offer ample protection to human settlers.
“Caves and their entrances have been proposed as habitable environments and regions that could have preserved evidence of life, mostly due to their natural shielding from the damaging ionizing and non-ionizing radiation present on the surface. However, no studies to date have quantitatively determined the shielding offered by these voids on Mars,” the researchers wrote in the journal Icarus.
The researchers found that the levels of UV radiation inside Martian caverns were, in some cases, ~2% of those values found on the surface.
“Numerical simulations of cave entrances show a reduction even more than two orders of magnitude in UV radiation, both in the maximum instantaneous and cumulative doses, throughout the year and at any location of the planet,” the researchers found.
What’s more, the amount of active radiation is still higher than the minimum required for Earth-like photosynthesis. In other words, cave entrances could shelter both humans and their plant food source. However, it’s unclear whether ionizing radiation — the kind of electromagnetic radiation associated with cancer — is blocked in the same way as UV radiation.
“Ionizing radiation doesn’t present exactly the same behavior as UV radiation,” Viúdez-Moreiras. told New Scientist. “However, it is expected that ionizing radiation will also be strongly attenuated in pit craters and cave skylights.”
In 2009, researchers led by Dr. Armando Azua-Bustos, a scientist at the Department of Planetology and Habitability Center of Astrobiology (CSIC-INTA) in Madrid, described the behavior of a particular Cyanidium eukaryote red algae growing in the Mars-like Atacama Desert. These microorganisms formed biofilms in seemingly inhospitable coastal caves where there is little light, but just enough it seems to support life. If Martian caves are anything like those across the barren Atacama Desert, the driest place on Earth, life could find a way to thrive there as well, Azua-Bustos and colleagues proposed.
High-resolution surface imaging data recorded over the past couple of decades by instruments like the Mars Reconnaissance Orbiter Context Camera system (CTX), together with Mars Odyssey’s thermal emission imaging system (THEMIS), suggest that the Tharsis bulge may be the best region for cave candidates on Mars. More than 1,000 suitable caves have been identified in this region, which also contains three enormous shield volcanoes, Arsia Mons, Pavonis Mons, and Ascraeus Mons.
Tharsis city sounds like an awesome name for the first human settlement on Mars. Remember the name.
UPDATE (August 30, 2021): The article was updated to include the findings made by Azua-Bustos et al. in the Atacama Desert, which complement the radiation quantification in Martian caves.
Where there’s water, there’s life — but Mars may not be as watery as we thought. We already knew that liquid water can’t really last on the surface: it would evaporate in no time. We also knew that water ice is plentiful in some areas on Mars. But what about liquid water?
Based on observations in 2018, astronomers started to suspect that Mars may have underground lakes beneath some masses of ice. This was based on observations from a radar instrument aboard the ESA (European Space Agency) Mars Express orbiter.
The idea isn’t as crazy as it sounds. Earth also has a lot of underground water, and even frozen moons like Europa or Ganymede are thought to have large masses of subsurface water. Mars having a subsurface lake below its ice cap wouldn’t be all that weird — especially as the data seemed to back it up.
But the data may not back it up after all.
Radar instruments send out pulses of electromagnetic waves; the wave passes through different materials (in this case, the layers of Mars), and based on the electromagnetic properties of the material, a receiver captures the reflected waveform.
The initial analysis of this radar data showed some strong reflections, which researchers interpreted as bodies of water. But in a new study, Isaac Smith of Toronto’s York University now has a different idea.
Smith didn’t go to Mars or anything like that — he worked in a lab, freezing clays with liquid nitrogen, until they reached temperatures like those on Mars.
“The lab was cold,” Smith said. “It was winter in Canada at the time, and pumping liquid nitrogen into the room made it colder. I was bundled up in a hat, jacket, gloves, scarf, and a mask because of COVID-19. It was pretty uncomfortable.”
The clays in this case are called “smectites” — a type of rock formed by liquid water long time ago. He then subjected them to radar instruments similar to those used on Mars, to see their response. It was exactly like what the Mars Orbiter observed.
In a recent paper published in Geophysical Research Letters, researchers found that many of the “water” signals came from areas close to the surface, where it should be too cold for water to remain liquid, even when mixed with minerals commonly found on Mars (that can lower freezing temperature of water).
So we know that it’s probably too cold for liquid water to exist in those areas, and we have another likely candidate that could be responsible for the signal. Although it’s not yet possible to directly confirm whether what was on the radar data was liquid water, smectites, or maybe even something else, water is looking less and less likely.
But this is a win for science. Ultimately, the fact that researchers are able to derive so much information about a different planet, working with so little data, is remarkable.
“In planetary science, we often are just inching our way closer to the truth,” said Jeffrey Plaut of NASA’s Jet Propulsion Laboratory. “The original paper didn’t prove it was water, and these new papers don’t prove it isn’t. But we try to narrow down the possibilities as much as possible in order to reach consensus.”
With its 10th flight on Mars completed just yesterday, NASA’s Ingenuity helicopter has now flown more than a mile through the skies of our red neighbor.
In a Twitter post on Sunday, NASA confirmed that Ingenuity flew over the “Raised Ridges”, part of a fracture system inside Jezero Crater that researchers have been looking to investigate for some time now. These fractures can act as pathways for fluids underground so, if there’s water on Mars (or if there was water on Mars), these fractures would hold signs of its passing. This marked the 10th flight for the helicopter drone, and its first full mile over Mars.
“With the Mars Helicopter’s flight success today, we crossed its 1-mile total distance flown to date,” officials with NASA’s Jet Propulsion Laboratory in Pasadena, California wrote in an Instagram update late Saturday. JPL is home to the mission control for Perseverance and Ingenuity.
In an earlier Tweet, Ingenuity operations lead Teddy Tzanetos described the planned flight in a status update, calling it the most complex mission the drone has undergone so far, in terms of both navigation and performance. The helicopter was sent to investigate (fly over and photograph) 10 sites, with the mission estimated to last around 165 seconds.
Although the full details of the mission haven’t been published yet, Tzanetos explained on Friday that it would be taking off from its sixth airfield and then moving south-by-southwest about 165 feet (50 meters). From there, it was scheduled to take two pictures of Raised Ridges from two different angles, both looking south. From there, Ingenuity was scheduled to fly west and then northwest, to snap further images of the Raised Ridges area. These will be used by NASA to create stereo images of the area.
What we do know is that during the flight, Ingenuity achieved a new record height: 40 feet (12 meters) above ground.
Ingenuity was meant to operate on mars for around 30 days; it has now been hard at work for 107. It went well beyond its duties during this time, allowing ground control to test out several flight maneuvers and undergoing two software updates — one to improve its flight speed, the other to refine its camera’s color-capturing abilities. To date, it’s flown for 14 minutes on Mars, which is a bit over 112% the performance target used for tech demos back on Earth.
Still, it shows no signs of slowing down anytime soon. Since it’s running on solar panels, fuel isn’t a concern, and NASA has already extended its operations once (after Ingenuity completed its primary mission in April). We’re likely to see a similar extension in the future, as the craft is providing invaluable reconnaissance from the skies of Mars.
While Martian rovers like Curiosity or Perseverance take the spotlight, it’s the InSight lander that can help us look deep into the Red Planet. In a set of new papers, researchers analyzing 174 marsquakes presented the most in-depth data of the Red Planet, including data on its crust, mantle, and molten core.
The pulse of Mars
The three papers each focused on one of the main layers of Mars: the crust, the mantle, and the core. If those three sound familiar — well, it’s because they’re also the layers of the Earth. Researchers have known that Mars must have a similar structure of a while, but as to the detailed structure of these three layers, that’s little more than an educated guess based on gravitational measurements.
NASA’s InSight mission wanted to change that. Using its Seismic Experiment for Interior Structure (or SEIS) seismometer tool, the space agency can monitor marsquakes — or, if you will, earthquakes on Mars. The seismometer can measure the pulse of Mars by studying waves created by marsquakes, thumps of meteorite impacts, and even surface vibrations generated by activity in Mars’ atmosphere and by weather phenomena such as dust storms.
Believe it or not, most of what we know about the Earth’s deep structure comes from earthquakes. It’s not that researchers haven’t tried digging or studying the subsurface in other ways, but even the deepest hole we’ve dug doesn’t even come close to the mantle — let alone the core. So instead, researchers turned to the field of seismology to fill in the gaps.
Earthquakes (and marsquakes) produce seismic waves that spread through the planet. Like acoustic waves that reflect off of walls or other surfaces, seismic waves also reflect (or refract) when they encounter different surfaces. InSight’s SEIS tool can capture data from these waves, and based on this data, enable researchers to assess the Martian subsurface.
“What we’re looking for is an echo,” said Amir Khan of ETH Zurich, lead author of the paper on the mantle. “We’re detecting a direct sound – the quake – and then listening for an echo off a reflector deep underground.”
Another piece of important information comes from the speed of seismic waves — especially
Understanding the Red Planet
Of course, while we have thousands of seismometers on Earth, we only have one on Mars, so the level of detail we can obtain is far lower — but it’s still better than anything we’ve had so far.
The first step is establishing just how big these large layers are, and then look for any details that can be pieced together.
“Layering within the crust is something we see all the time on Earth,” said Brigitte Knapmeyer-Endrun of the University of Cologne, lead author on the paper about the crust. “A seismogram’s wiggles can reveal properties like a change in porosity or a more fractured layer.”
The first finding was that the crust was thinner than expected, and that it appears to have two or three sub-layers. It goes as deep as 12 miles (20 km) if it has two sub-layers, or 23 miles (37 km) if there are three.
Extrapolated across the planet, this suggests the Martian crust averages between 24 and 72 kilometers thick, and “both of those are actually on the thin end of our pre-mission expectations,” Panning says. Some models had previously put the crust at 100 kilometers thick, but according to these results, that’s not exactly the case. Earth’s crust is 5 to 70 km thick.
Meanwhile, the mantle goes down 969 miles (1,560 km), and the core has a radius of 1,137 miles (1,830 km). The Martian mantle doesn’t have the depth and pressure needed to create a lower mantle — a type of layer that is present on Earth. This layer helped insulate the Earth’s core when the planet formed, so without it, Mars may have cooled much faster than the Earth (also depending on what the core is made of).
Researchers also explain that the core must be molten — if it were solid, some of the observed waves wouldn’t have been possible.
Where no man has gone before
The study offers an unprecedented opportunity to understand not just the structure of Mars, but the structure of all rocky planets.
“This study is a once-in-a-lifetime chance,” said Simon Stähler of the Swiss research university ETH Zurich, lead author of the core paper. “It took scientists hundreds of years to measure Earth’s core; after the Apollo missions, it took them 40 years to measure the Moon’s core. InSight took just two years to measure Mars’ core.”
Unlike Earth, Mars doesn’t have any big earthquakes, because it doesn’t have any tectonic plates. The vast majority of earthquakes on Earth happen due to the movement of these tectonic plates, whereas on Mars, quakes are caused by rock faults, fractures, landslides, or by the rocks contracting as the planet continues to cool — which means these earthquakes are not as strong. Out of the 174 recorded quakes, not one was over 4.0 in magnitude.
“We’d still love to see the big one,” said JPL’s Mark Panning, co-lead author of the paper on the crust. “We have to do lots of careful processing to pull the things we want from this data. Having a bigger event would make all of this easier.”
InSight’s way around this challenge is through precision: it can measure vibrations on the scale of a hydrogen atom, and without the oceans and human activity to create noise, it can measure much more peacefully.
This is the first time we have information about another planet’s core and mantle. Researchers have previously only mounted seismometers on Earth and the Moon.
As InSight records data from more marsquakes, NASA researchers will continue to analyze them and piece together more and more information about the Red Planet’s inside. After all, you don’t get the chance to find a planet’s core very often.
We are closer than ever before to understanding the composition of Mars thanks to the first observations of seismic activity on the planet made by the InSight lander. The NASA-led project, which landed on the surface of the Red Planet in November 2018 with the goal of probing beneath the Martian surface, observed several so-called ‘marsquakes’ which reveal details about its crust, mantle, and core.
InSight’s primary findings which are detailed in three papers published today in the journal Science, represent the first time scientists have been able to produce a detailed picture of the interior of a planet other than Earth.
“We are seeking to understand the processes that govern planetary evolution and formation, to discover the factors that have led to Earth’s unique evolution,” says Amir Khan, ETH Zurich and the University of Zurich, whose team used direct and surface reflected seismic waves to reveal the structure of Mars’ mantle. “In this respect, the InSight mission fills a gap in the scientific exploration of the solar system by performing an in-situ investigation of a planet other than our own.”
The results from the ongoing NASA mission–with the full title ‘Interior Exploration using Seismic Investigations, Geodesy and Heat Transport’— could reveal key insights into the Red Planet‘s formation and evolution, as well as helping us understand the key differences between our planet and Mars.
“One big question we would like to understand is why Earth is the only planet with liquid oceans, plate tectonics, and abundant life?” adds Khan. “Mars is presently on the edge of the solar system’s habitable zone and may have been more hospitable in its early history. Whilst we don’t yet know the answers to these questions, we know they to be found are on Mars, most likely within its interior.”
InSight first detected the presence of marsquakes from its position in Elysium Planitia near the Red Planet’s equator in 2019 and has since picked up more than 300 events–more than 2 a day–tracing many of them back to their source.
What is really impressive is what researchers can do with these quakes, using them as a diagnostic tool to ‘see’ deep into the planet’s interior.
“Studying the signals of marsquakes, we measured the thickness of the crust and the structure of the mantle, as well as the size of the Martian core,” Simon Stähler, a research seismologist at ETH Zurich, tells ZME Science. “This replicates what was done on Earth between 1900 and 1940 using the signals of earthquakes.”
From the Crust of Mars…
The observations made by InSight have allowed researchers to assess the structure of Mars’ crust, allowing them to determine its thickness and other properties in absolute numbers for the first time. The only values we previously had for the Martian crust were relative values that showed differences in thickness from area to area.
“As part of the bigger picture on the interior structure of Mars, we have determined the thickness and structure of the Martian crust,” Brigitte Knapmeyer-Endrun, a geophysicist at the University of Cologne’s Institute of Geology, tells ZME Science. “Previous estimates could only rely on orbital data–gravity and topography–that can accurately describe relative variations in crustal thickness, but no absolute values. These estimates also showed a wide variability.”
With data collected regarding the crustal thickness at InSight’s landing area, new seismic measurements, and data collected by previous missions, the team could map the thickness across the entire Martian crust finding an average thickness of between 24 and 72 km.
Knapmeyer-Endrun explains that the data she and her team collected with InSight’s Seismic Experiment for Interior Structure (SEIS), particularly the very broad-band (VBB) seismometer–an instrument so sensitive it can record motion on an atomic scale–and information from the Marsquake Service (MQS) at ETH Zurich, suggest that the Red Planet’s crust is thinner than models have thus far predicted.
“We end up with two possible crustal thicknesses at the landing site–between 39 and 20 km– but both mean that the crust is thinner than some previous estimates and also less dense than what was postulated based on orbital measurements of the surface.”
Knapmeyer-Endrun continues by explaining that the InSight data also reveals the structure of the Martian crust as multi-layered with at least two interfaces that mark a change in composition. In addition to this, the team can’t rule out the presence of a third crustal layer before the mantle.
“The crust shows distinct layering, with a surficial layer of about 10 km thickness that has rather low velocities, implying that it probably consists of rather porous–fractured–rocks, which is not unexpected due to the repeated meteorite impacts,” says the geophysicist adding that we see something similar on the Moon, but the effect is more extreme due to that smaller body’s much thinner atmosphere.
Knapmeyer-Endrun is pleasantly surprised regarding just how much information InSight has been able to gather with just one seismometer.”It’s surprising we were really able to pull all of this information about the interior of Mars from the recordings of quakes with magnitudes of less than 4.0 from a single seismometer,” she explains. “On Earth, we would not be able to even detect those quakes at a comparable distance. We typically use 10s or even 100s of seismometers for similar studies.”
And the marsquake data collected by InSight has not just proven instrumental in assessing the thickness and composition of the planet’s crust, it has also allowed scientists to probe deeper, to the very core of Mars itself.
…To the Martian Mantle and Core
Using direct and surface reflected seismic waves from eight low-frequency marsquakes Khan and his team probed deeper beneath the surface of Mars to investigate the planet’s mantle. They found the possible presence of a thick lithosphere 500km beneath the Martian surface with an underlying low-velocity layer, similar to that found within Earth. Khan and his co-author’s study reveals that the crustal layer of Mars is likely to be enriched with radioactive elements. These elements heat this region with this warming reducing heat in lower layers.
It was these lower regions that Stähler and his colleagues investigated with the use of faint seismic signals reflected by the boundary between the Martian mantle and the planet’s core. What the team discovered is that the Red Planet’s core is actually larger than previously calculated, with a radius of around 1840 km rather than previous estimates of 1600km. This means the core begins roughly halfway between the planet’s surface and its centre.
From the new information, we can also determine the core’s density and extrapolate its composition.
“We now know for sure the size of the core and it’s significantly larger than it had been thought to be for a long time,” says Stähler. “Because we found that the core is quite large, we, therefore, know it is not very dense. This means that Mars must have accumulated a substantial quantity of light, volatile elements such as sulfur, carbon, oxygen, and hydrogen.”
This ratio of lighter elements is greater than that found within Earth’s denser core, and it could give us important hints about the differences in the formation of these neighbouring worlds.
“Somehow these light elements needed to get into the core. It may mean that the formation of Mars happened faster than Earth’s,” Stähler says. “These observations have fueled speculation that Mars might represent a stranded planetary embryo that depicts the chemical characteristics of the solar nebula located within the orbit of Mars.”
As just Knapmeyer-Endrun did, Stähler expresses some surprise regarding just how successful InSight has been in gathering seismological data, emphasising the role good fortune has played in the mission thus far.
“We were able to observe reflections of seismic waves from the core–like an echo–from relatively small quakes. And the quakes were just in the right distance from the lander. Had we landed in another location, it would not have worked out,” the seismologist says. “And the landing site was only selected because it was flat and had no rocks, so it was really pure luck.”
Stähler says that he and his team will now attempt to use seismic waves that have crossed the core of Mars to determine if the planet’s core possesses a solid-iron inner-core like Earth, or if it is entirely liquid. Just one of the lingering questions that Knapmeyer-Endrun says InSight will use marsquakes to tackle over the coming years.
“There are still multiple open questions that we’d like to tackle with seismology. For example, which geologic/tectonic features are the observed marsquakes linked to? At which depth do olivine phase transitions occur in the mantle? And Is there a solid inner core, like on Earth, or is the whole core of Mars liquid?” says the geophysicist.
And if we are to go by track record, the smart money is on InSight answering these questions and more. “Within just 2 years of recording data on Mars, this single seismometer has been able to tell us things about the crust, mantle and core of Mars that we’ve been speculating about for decades.”
A nail-biter of a flight saw Ingenuity take to the Martian skies for 166.4 seconds and reaching a maximum speed of 5 m/s (or 10 mph, the speed of a brisk run). During this flight, Ingenuity covered about 625 meters (2,050 feet), showcasing the advantages that flight missions can offer for exploring new planets.
NASA’s Mars helicopter Ingenuity is the first aircraft ever to fly on a celestial body other than the Earth. Ingenuity was only meant to serve as a proof of concept, showing that flight on Mars (in a thin, rarefied atmosphere) can be done. It was only meant to carry out three flights as a proof of concept — but now, Ingenuity just completed its ninth flight, and a daring one at that.
For its latest flight, Ingenuity flew from the Perseverance rover, taking a shortcut to the Séítah region (meaning “amidst the sand” in Diné Bizaad, the Navajo language). Séítah is interesting to researchers but is difficult to cover by land due to its sandy ripples. Flying Ingenuity over the area was a risk and NASA acknowledged it was pushing the vehicle past its limits — but the risk paid off.
Flying across the Martian dunes 183 million miles from the Earth, Ingenuity clearly showed its worth, not just by exploring otherwise inaccessible terrain, but also through the distance it covered on Mars.
The distance covered by Ingenuity in this single flight is comparable to what the Spirit rover has explored in its entire mission on the Red Planet.
“We believe Ingenuity is ready for the challenge, based on the resilience and robustness demonstrated in our flights so far,” NASA said in a press release. “Second, this high-risk, high-reward attempt fits perfectly within the goals of our current operational demonstration phase. A successful flight would be a powerful demonstration of the capability that an aerial vehicle, and only an aerial vehicle, can bring to bear in the context of Mars exploration.”
Until now, Ingenuity has kept close to its terrestrial exploration partner — the Perseverance rover. This is the main operation NASA is looking at (the ability of a flying craft to accompany an extraterrestrial rover) but Ingenuity is increasingly showing that it can do a lot of things on its own.
The flight was a nerve-wracking one, though. Ingenuity’s navigation system wasn’t meant to deal with this type of fluctuating topography, so the team had to work around this difficulty.
In the end, although NASA hasn’t released any data from the flight, the mission proved to be a success. Not only did Ingenuity manage to take photos of previously unexplored terrain, but it also showed that its operational limits can be stretched even further. We have likely not seen the full range of what the brave little helicopter can accomplish.
After sending a few photos of its landing site, China’s Mars rover is now driving around and exploring the surface, said state-run Xinhua news agency said.
The first images beamed back by Zhurong were black-and-white images taken by the rover’s obstacle avoidance camera, as well as a color image taken by a navigation camera of the rear of the rover showing that its solar panel and antenna have unfolded normally, China’s Space Administration (CNSA) said.
China is now only the second nation after the United States to successfully put a probe on the surface of Mars and operate it for a significant length of time. Chinese scientists hope to get at least 90 Martian days of service out of the six-wheeled robot at its location on Utopia Planitia, a vast terrain in the planet’s northern hemisphere.
Zhurong, named after a god of fire in Chinese mythology, weights 240 kilograms and is equipped with six scientific instruments. It was launched by a type of rocked called Long March 5 from the Wenchang Spacecraft Launch Site in Hainan, China, on July last year. The rover then spent seven months en route to Mars before entering its orbit.
Its mission is to study the planet’s topography, geology, and atmosphere, seeking to understand the distribution of ice in the region. A tall mast carries cameras to take pictures and aid navigation, while five additional instruments will investigate the mineralogy of local rocks and the general nature of the environment, including the weather.
The mission, named Tianwen-1 or “Quest for Heavenly Truth,” is one of three that launched last summer, along with NASA’s Perseverance rover, which landed on Mars in February, and the United Arab Emirates’ Hope Probe. Unlike the US and China, the UAE probe is not intended to land on Mars but instead to study the planet from orbit.
“As the international scientific community of robotic explorers on Mars grows, the United States and the world look forward to the discoveries Zhurong will make to advance humanity’s knowledge of the Red Planet,” Bill Nelson, NASA’s administrator, said in a statement, congratulating China on the first images of the mission.
China’s President Xi Jinping sent his congratulations on the successful Mars mission, hailing it as an “important step in China’s interstellar exploration.” China had already attempted to reach Mars in 2011 with the Yinghuo-1 probe. But the mission failed due to a malfunction that stranded the probe in Earth’s orbit shortly after launch.
The country’s space program reached world headlines earlier this month because of an out-of-control rocket that plunged into the Indian Ocean. The rocket, Long March 5B, had launched as part of China’s new space station into orbit in late April and had then been left to hurtle through space uncontrolled until Earth’s gravity pulled it back in.
China is already a space power in its own right, after sending astronauts into space, powering probes to the Moon, and landing; only the US and Russia can claim this. China still has a way to go to catch up with the US and Russia, as it’s lacking the decades of experience the two countries can boost
China has come a long way in its race to catch up with the United States and Russia, whose astronauts and cosmonauts have decades of experience in space exploration, but it’s making great strides. Already, China wants to send people to its new lunar station by 2022.
However, the country has also drawn international criticism recently due to its inability to control return of one of its rockets, which ultimately disintegrated over the Indian Ocean in an uncontrolled landing back to Earth.
China successfully landed its six-wheeled Zhurong rover on Mars, early on May 14. Similar to the touchdown of its American counterpart, Perseverance, which reached the red planet in February, the Chinese vehicle used a combination of a protective capsule, a parachute, and a rocket platform to make the descent. Now, Zhurong has released its first pictures from the Utopia Planitia landing site, a vast region in the planet’s northern hemisphere.
Up until Zhurong, only NASA had mastered landing on Mars. All other countries that tried before either crashed or lost contact soon after their vehicle reached the surface.
Zhurong, which means God of Fire, was carried to Mars on the Tianwen-1 orbiter, which arrived above the planet in February. Since then, the probe had been patiently orbiting the planet, surveying Utopia Planitia in search of the safest place to target a landing.
The images released by the China National Space Administration include a black-and-white photo taken by the obstacle avoidance camera from the front of the rover, showing a ramp from the lander extending to the surface. The message is clear: this is supposed to be the historical moment right before the rover’s wheels touch the surface of Mars.
The second image is in color and shows the back of Zhurong, including the rover’s antenna and fully deployed solar panels.
Additionally, China released a brief video showing the lander separating from the orbiter that carried the rover to Mars. This dive through Mars’ atmosphere, known as the “seven minutes of terror”, is considered the most challenging part of any voyage to Mars’ surface.
Zhurong’s successful landing on Mars is the latest in a series of major milestones for China’s space program. In December 2020, China successfully landed a spacecraft on the moon’s surface in a mission to retrieve lunar surface samples, only the third country to do so after the United States and the Soviet Union decades ago. In 2016, China launched its second space laboratory, Tiangong 2, and is planning the launch of a third space station soon.
Unlike its American predecessors, Zhurong has a very flexible schedule. Its mission is set to run for only 90 days during which it will use its instruments to investigate local rocks and the general natural environment, including the weather. The colossal Utopia Planitia basin, measuring over 3,000 kilometers across, was formed by an impact early in the planet’s history. Scientists believe it once held an ancient ocean.
The next rover bound for Mars is Rosalind Franklin, previously known as the ExoMars rover, part of the international ExoMars program led by the European Space Agency and the Russian Roscosmos State Corporation. The mission was scheduled to launch in July 2020 but was postponed to 2022.
It came, it saw, it conquered — after four successful return flights, Ingenuity (the first man-made machine to take flight on another planet) is now embarking on a new adventure: flying from place to place, accompanying the Perseverance rover, and studying Mars from above.
There’s a drone *on Mars*
Ingenuity was meant to be just a proof of concept, a stepping stone for future missions. But it already is more than just that.
After having its Wright Brothers moment and taking off in a rarefied atmosphere (the Martian atmosphere is just 1% as dense as that on the Earth), it carried out three more flights, each longer than the previous. For each of these flights, though, it went in one direction and then returned to its original launch area (named after the Wright Brothers).
The fifth flight was different, though. After rising up to 33 feet (10 meters) and capturing high-resolution color images of its new neighborhood, it went south and safely landed at a new location.
“We bid adieu to our first Martian home, Wright Brothers Field, with grateful thanks for the support it provided to the historic first flights of a planetary rotorcraft,” said Bob Balaram, chief engineer for Ingenuity Mars Helicopter at JPL. “No matter where we go from here, we will always carry with us a reminder of how much those two bicycle builders from Dayton meant to us during our pursuit of the first flight on another world.”
A new step
The flight marks a transition to a new phase in its mission. This will focus on assessing what capabilities such a device can provide, especially as a complement to the Perseverance rover. The helicopter can scout and provide detailed aerial imaging, information that could greatly benefit future exploration missions on Mars. The rover-helicopter duo will work together to unlock unprecedented research capability.
So far, everything is going according to plan — which, when you’re working remotely with instruments on another planet, is already a fantastic achievement. But in some regards, Ingenuity is even surpassing what its engineers had hoped for.
“The power system that we fretted over for years is providing more than enough energy to keep our heaters going at night and to fly during the day,” a NASA press release mentioned. “The off-the-shelf components for our guidance and navigation systems are also doing great, as is our rotor system. You name it, and it’s doing just fine or better.”
Of course, at any point, something could go wrong. After all, Ingenuity has fulfilled its original mission and is now trying on an extended schedule (proof that even on Mars, those that work well are assigned overtime).
NASA engineers are fully aware of the risks, and they’re taking things step by step.
“We will now be flying over unsurveyed terrains and transfer to airfields that are not well characterized so there’s a higher probability of a bad landing,” explained MiMi Aung, Ingenuity’s project manager.
“We will be celebrating each day that ingenuity survives and operates beyond the original window.”
“The plan forward is to fly Ingenuity in a manner that does not reduce the pace of Perseverance science operations,” said Balaram. “We may get a couple more flights in over the next few weeks, and then the agency will evaluate how we’re doing. We have already been able to gather all the flight performance data that we originally came here to collect. Now, this new operations demo gives us an opportunity to further expand our knowledge of flying machines on other planets.”
Still, it’s hard to not get excited at the prospect of a helicopter assisting a rover to explore another planet. It’s barely been a century since the first human flight, and now we’re already sending flying devices to other planets. Just a few decades ago, this would have seemed like science fiction more than an actual possibility — yet here we are.
We hope to be reporting on Ingenuity for a long time.