Tag Archives: InSight

NASA’s InSight probe peers into the heart of Mars, sees Earth-like layers

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.

Illustration of Mars’ internal structure. Image credits: IPGP / David Ducros.

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.

The inner layers of Mars are similar in nature with those on Earth, but their structure and size are very different. Image credits: Chris Bickel/Sciencel

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.

Clouds drift over the dome-covered seismometer, known as SEIS, belonging to NASA’s InSight lander, on Mars. Image credits: NASA / JPL.

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

In this artist’s concept of NASA’s InSight lander on Mars, layers of the planet’s subsurface can be seen below and dust devils can be seen in the background. Credits: IPGP/Nicolas Sarter.

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.

The two largest quakes detected by NASA’s InSight appear to have originated in a region of Mars called Cerberus Fossae, an area that was linked with landslides. Credits: NASA/JPL-Caltech/Univ. of Arizona.

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.

InSight maps Mars’ composition and chunky core for the first time

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.

Using seismic activity or ‘marsquakes’ researchers have detailed the composition of the Martian interior for the first time (Cottaar/ Science)

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.”

The InSight Lander on the surface of Mars ((NASA/JPL-Caltech))

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.”

The Mars InSight lander’s seismometer consists of a protective dome that contains three extremely sensitive sensors. (NASA/JPL-Caltech)

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.

The two largest quakes detected by NASA’s InSight appear to have originated in a region of Mars called Cerberus Fossae. Scientists previously spotted signs of tectonic activity here, including landslides. This image was taken by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter (NASA/JPL-Caltech/University of Arizona)

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.

A Comparison of Mars’ Earth’s interiors. The Martian core shown here is smaller than these new findings suggest. Whilst the crust shown is thicker.

“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.”

Thanks to NASA's InSight Mars mission we now have a good picture of the interior of another planet.
InSight captures an image of its landing site, which proved the ideal vantage point to observe marsquakes (NASA)

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.”

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

Life could have prospered beneath the surface of Mars

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

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

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

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

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

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

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

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

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

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

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

Did Life on Mars prosper Beneath its Surface?

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

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

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

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

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


NASA finds Mars’ magnetic field is 10 times stronger than expected

Part of the reason why Earth is a world teeming with life while Mars is a barren wasteland is due to the presence of our planet’s magnetic field. This invisible barrier shields the atmosphere from the harmful effects of the solar wind.

But, that’s not to say Mars doesn’t have a planetary magnetic field at all — it’s just tiny relative to Earth’s. Now, NASA’s InSight lander has found it’s actually 10 times stronger than expected.

Illustration of NASA's InSight quake-monitoring lander. Credit: NASA.
Illustration of NASA’s InSight quake-monitoring lander. Credit: NASA.

Unlike other NASA missions to the Martian surface, InSight isn’t a rover — it’s a static lander.

It touched down on the red planet surface about a year and a half ago with two major goals. One is understanding how rocky planets formed and evolved by measuring the interior structure and processes of Mars. The other is figuring out just how tectonically active Mars is today, and how often meteorites impact it.

InSight was the first mission to measure seismic activity on Mars. It also has a magnetic sensor that allows InSight to measure the strength of the magnetic field at the lander location, a hallow crater called “Homestead hollow”, found in a flat region called Elysium Planitia.

Previously, the only reliable measurements of Mars’ magnetic field were performed by orbiting satellites that were hovering hundreds of kilometers from the red planet’s surface.

According to the measurements reported in Nature Geosciences, Mars’ magnetic field is actually 10 times stronger than scientists were led to believe from satellite readings. This would make Mars’ magnetic field, while still very weak compared to Earth’s much stronger than initially thought.

Earth’s magnetic field is generated by the motion of molten iron alloys in its outer core, which acts as a planetary dynamo, generating a massive magnetic field called the magnetosphere. It extends for several tens of thousands of kilometers into space, well above the atmosphere, sheltering the planet from charged particles of the solar wind and cosmic rays that would otherwise strip away the upper atmosphere, including the ozone layer that protects life from harmful ultraviolet radiation.

Earth isn’t unique in this respect. Jupiter has masses of liquid metallic hydrogen in its outer mantle, creating the largest planetary magnetic field in the solar system. Uranus generates a global magnetosphere closer to the surface, which leads to some very strange quadrupole field effects —  rather than just a north and a south, there are another two poles. Mars also used to have a magnetic field, but it suddenly switched off around four billion years ago.

Scientists aren’t sure how the red planet lost its magnetosphere but there are currently two leading theories. The first says that its core shut down, deactivating the dynamo and consequently Mars’ global magnetic field. The other leading hypothesis suggests that massive heat generated by large asteroid impacts warmed the outer layer of the planet to such a degree that it shut down convection from the hot core to the mantle.

After Mars’ lost its magnetic field, the atmosphere soon followed. With nothing to shelter it from cosmic rays and solar storms, the atmosphere thinned to the point that it’s now roughly 100 times less dense than Earth’s atmosphere. Mars is still continuously losing its atmosphere at a rate of about 100 grams of atmospheric gas every second.

According to NASA, there are still ‘fossil’ magnetic fields embedded in certain features of the red planet’s surface. The magnetic field recently measured by InSight is believed to emanate from very old rocks that are several hundred meters below the surface.

“Geological mapping and InSight seismic data suggest that much or all of the magnetization sources are carried in basement rocks, which are at least 3.9 billion years old and are overlain by between 200 m and ~10 km of lava flows and modified ancient terrain,” the authors of the new study wrote.

The new measurements of the red planet’s magnetic field change nothing about the prospects of finding life on Mars. It’s still very low — so low that the InSight lander could also easily detect solar wind in its vicinity. Nevertheless, the new findings add to a growing body of knowledge about Mars’ internal structure and geological history.

NASA puts InSight experiment on hold because one stubborn rock is blocking their instruments

A key instrument on NASA’s Mars InSight rover has run into a problem — ground control suspects a stone.

Mars landing.

A rendering of a InSight Mission Candidate Landing Site made using topography data from the University of Arizona / NASA/.
Image credits Kevin Gill / Flickr.

The rover’s heat probe has struck an obstacle just below the red planet’s surface over the weekend and hasn’t been able to make progress since.

The Heat Flow and Physical Properties Package Problem

“The team has therefore decided to pause the hammering for about two weeks to allow the situation to be analyzed more closely and jointly come up with strategies for overcoming the obstacle,” Tilman Spohn, the principal investigator for the heat probe, wrote Tuesday in the mission logbook.

The instrument, known as the Heat Flow and Physical Properties Package, or HP³, was designed to hammer itself 16 feet (roughly 5 meters) into Mars’ underground and measure how much heat its interior leaks. This data would help researchers estimate the planet’s composition and history.

However, trouble is brewing underneath InSight — this probe (nicknamed the “mole”) encountered some kind of resistance underground over the weekend and hasn’t been able to make any progress since. Ground control (at the Jet Propulsion Laboratory in La Canada Flintridge, California) first tried to power it up last week. This first attempt failed to reach all the way to the Mars Odyssey orbiter, however, which was supposed to pass it on to InSight.

The mole was deployed last Thursday, after the team established a stable connection to the rover. It pushed its way in the red soil and made quick progress. For about five minutes. The next four hours of hammering failed to push the mole much deeper and eventually forced the device to one side — the mole is now lodged in the underground, leaning at about 15 degrees of vertical.


Artist’s concept of InSight and its instruments.
Image credits NASA / JPL-Caltech.

Current estimates place the mole at a depth of around one foot (0.3 meters). This means that the probe — measuring some 16 inches (0.4 meters) in height — is partially sticking out of the ground. Despite this, the probe likely still is burrowed “deeper than any other scoop, drill or probe on Mars before,” which was its intended purpose.

Spohn writes that the team is a bit worried but that they “tend to be optimistic.” They’re currently working on the assumption that the holdup is a buried boulder or some gravel.

This particular spot was picked for InSight to land on as it appeared to be mostly sandy and soft. However, the team was aware that such a holdup was possible. Tests carried out at JPL suggested that the probe should be able to dig its way around small rocks or layers of pebbles. Since the second attempt to hammer away at the probe didn’t do that, the team decided to put the mole on hold. They’re currently waiting to receive more data from InSight, including pictures, so they can “better assess the situation.”

But not all is lost. The probe is still intact — that’s a really good thing — so it can actually start collecting data. The team has already put it to the task. HP³ will measure how quickly a generated pulse of heat spreads through the soil. Later this week, as (Mars’ moon) Phobos passes overhead and eclipse the sun over InSight the probe will also track how the event changes surface temperatures. While not its intended role, these readings should help the team make better sense of heat flow values in Mars’ soil if and when the probe is deployed as planned.

Three-day weather data for Mars at the site of InSight lander. Notice dips at 7 AM and 7 PM in air pressure section. Credit: NASA,

InSight lander detects mysterious dips in air pressure on Red Planet (and shares Martian weather forecast)

Illustration of InSight probe with its two main instruments deployed, a heat probe (left) and seismometer (bell-shaped, right). Credit: NASA.

Illustration of InSight probe with its two main instruments deployed, a heat probe (left) and seismometer (bell-shaped, right). Credit: NASA.

NASA’s InSight lander arrived on Mars in late 2018 tasked with the mission of studying the planet’s geology. Its main instrument is a seismometer which the probe will soon use to listen to marsquakes. However, the probe is also equipped with sophisticated meteorology gear like a highly sensitive air pressure sensor that is already revealing some unexpected surprises.

The Martian surface is very thin — less than one percent of Earth’s surface pressure — but it’s enough to accommodate weather and significant air pressure differences that cause the soil to slightly tilt and rumble. Therefore, InSight’s air pressure sensor data is essential to the probe’s missions since it calibrates the seismometer.

InSight’s mission is unlike that of any spacecraft we’ve ever sent to Mars. All of our past probes have studied the planet’s environment above ground, but InSight is focused on what happens beneath the surface by listening to ‘marsquakes’. By studying these slight seismic waves, scientists want to determine what makes up the planet’s mantle and core. Basically, InSight will study seismic waves as they pass through the Red Planet, using that information as a sort of ultrasound to find out what is lurking underneath the crust.

While the seismometer isn’t operational yet, NASA scientists have been busy studying data from other sensors, including those on temperature and air pressure. Some interesting discoveries include the presence of gravity waves, the displacement of a fluid from its position of equilibrium. These are not to be confused with gravitational waves, which are disturbances in the curvature (fabric) of spacetime, and most commonly during the evenings. And in the last 72 hours, researchers measured infrasound waves with a period of only one-hundredth of a hertz over a period of 100 seconds — that’s several octaves well below the range of human hearing. According to a Forbes report, the infrasounds may be caused by a meteor crashing into the red planet’s atmosphere, a landslide, or airflow over an underlying stable local atmosphere.

The most surprising finding is a strange pattern in the air pressure data, which shows surface pressure dipping slightly twice a day, at around 7 AM and 7 PM local time. Ars Technica reports that NASA has ruled out causes linked to the sensor or heating source.

Three-day weather data for Mars at the site of InSight lander. Notice dips at 7 AM and 7 PM in air pressure section. Credit: NASA,

Three-day weather data for Mars at the site of InSight probe. Notice dips at 7 AM and 7 PM in air pressure section. Credit: NASA,

Scientists think that this feature may be due to some atmospheric wave generated by the sunrise and sunset on Mars. Alternatively, downslope air flow passing by irregular topography might lead to brief atmospheric changes.

Perhaps this anomaly may be important in answering some questions regarding the formation of dust devils on Mars. These low-pressure whirlwinds can spin at up to nearly 60 miles an hours and reach colossal heights of 10 kilometers.

A dust storm ultimately sealed the fate of the iconic Opportunity rover, which was officially declared defunct last week. Most importantly, these atmospheric disturbances could threaten human lives when astronauts finally arrive on Mars. Before any boots touch Martian soil, NASA wants to understand what are the minimum winds required to lift dust off the surface in order to forecast dust storms and dust devils.

On a different note, NASA now also has an updated page where you can monitor the weather around InSight’s landing site at Elysium Planitia. This week temperatures varied between -17°C and -10°C (3°F and 15°F) during the day and hovered around -94°C (-140°F) during the night. 

Credit: NASA/JPL-Caltech.

InSight beams back its first selfie — and what a treat!

Credit: NASA/JPL-Caltech.

Credit: NASA/JPL-Caltech.

NASA’s rovers are pretty vain. For instance, Curiosity has taken so many selfies it could make an Instagram influencer blush. Why would InSight — which made the most recent landing on Mars — be any different?

The image that InSight recently beamed back together shows InSight in all its splendor, with its solar panels extended and deck fully loaded by scientific instruments. The view is actually a composite image that stitched together several different snapshots — 11 snapshots for the lander itself and 52 for the area in front of the lander. But if this is really a selfie, where’s the arm? In fact, since the mosaic was formed with pictures taken from different angles, the robotic arm that did all the shooting isn’t visible.

InSight wasn’t just vain, though. Having an overview of InSight’s landing site is important for the mission’s engineers. And if InSight’s surroundings look boring, that’s actually perfect, according to NASA.

“The near-absence of rocks, hills and holes means it will be extremely safe for our instruments,” Bruce Banerdt, InSight’s principal investigator, said in a press release.

“This might seem like a pretty plain piece of ground if it weren’t on Mars, but we’re glad to see that.”

InSight isn’t a rover. Instead, it will stay put for the duration of its two-year mission, which is why having a plain location is so important. Over the following weeks, the probe’s robotic arm will gently deploy the mission’s two most important instruments on the Martian surface: a seismometer and a heat probe.

The seismometer will ‘listen’ for marsquakes. By studying these slight seismic waves, scientists want to determine what makes up the planet’s mantle and core. Basically, InSight will study seismic waves as they pass through the Red Planet, using that information as a sort of ultrasound to find out what is lurking underneath the crust. The heat probe will drill down to 16 feet (4.8 meters) to measure temperature, which will be useful in geological studies of Mars.

This week, InSight also radioed the first recording of Martian wind.

InSight stretches its solar panels, beams back first clear photo from Mars

Landing on Mars is an incredibly challenging feat, a process that has claimed numerous probes and spacecraft over the last 50 years. On Monday, NASA landed its InSight Probe after it had traveled for six months through 300 million miles of space. According to the latest reports from NASA engineers, InSight has now deployed its array of solar panels so that it may recharge its batteries each day. The probe also beamed back its first clear photo of the Martian surface.

The picture was taken on November 26, 2018, the same day InSight landed on the Red Planet. The probe’s camera is still covered by a transparent dust cover meant to prevent damage to the lens upon landing. Credit: NASA/JPL-Caltech.

The signal that the solar panels had been deployed successfully was transmitted to Earth at about 5:30 p.m. PST (8:30 p.m. EST) by NASA’s Mars Odyssey orbiter. The twin solar arrays are each 7 feet (2.2 meters) wide, when fully open. This now makes the lander about the size of a large 1960s convertible. But because Mars is so much farther away from the Sun than Earth, the amount of sunlight that reaches the Red Planet is also weaker. The panels should provide about 600 to 700 watts of power on a clear day and 200 to 300 watts the panels are covered in dust, which is practically the norm. Luckily, the probe’s sophisticated instruments do not require a lot of energy and InSight’s solar arrays should be more than capable of recharging the batteries.

“The InSight team can rest a little easier tonight now that we know the spacecraft solar arrays are deployed and recharging the batteries,” Tom Hoffman, InSight’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California, said in a statement. “It’s been a long day for the team. But tomorrow begins an exciting new chapter for InSight: surface operations and the beginning of the instrument deployment phase.”

InSight’s mission is unlike that of any spacecraft we’ve sent to Mars. All of our past probes have studied the planet’s environment above ground, but InSight is focused on what happens beneath the surface by listening to ‘marsquakes’. By studying these slight seismic waves, scientists want to determine what makes up the planet’s mantle and core. Basically, InSight will study seismic waves as they pass through the Red Planet, using that information as a sort of ultrasound to find out what is lurking underneath the crust.

InSight will also help scientist come to a better understanding of how the solar system formed and evolved. Both Mars and Earth are rocky planets that had lots of water on their surface during their rich history. However, the two planets look very differently today — Earth is wet and teeming with life while Mars is barren and dead.

Next, NASA will use a robotic arm to deploy instruments on the surface of Mars, among them the precious seismometer and a heat flow probe. However, it will take at least three months before there will be any seismic data available. That’s because NASA wants to make sure that the instruments are properly set up and calibrated. Meanwhile, InSight will use its weather sensors and magnetometer to make measurements from its landing site at Elysium Planitia.

Artist impresion of the InSight probe gently touching down on Mars with its descent engines fired on. Credit: NASA.

Touchdown: NASA’s InSight probe safely lands on Mars

Artist impresion of the InSight probe gently touching down on Mars with its descent engines fired on. Credit: NASA.

Artist impresion of the InSight probe gently touching down on Mars with its descent engines fired on. Credit: NASA.

NASA just landed the InSight probe on Mars after traveling more than 300 million miles through space for 205 days. InSight slowed down from a staggering 12,300 mph to 5 mph in under 6 minutes, piercing through the thin Martian atmosphere while it deployed its parachute and descent engines.

NASA engineers held their breath witnessing the delicate transition from soaring through the Martian atmosphere at breakneck speed to gently touching down on the surface of the Red Planet. Among NASA scientists, this is known as “the seven minutes of terror” — because the landing is completely out of their direct control, and it takes about seven minutes, of course.

The one-of-a-kind Mars explorer landed on a region called Elysium Planitia, a flat landscape where it will study the slight rumbles and tremors produced as the planet wobbles. Just like ‘earthquakes’, these are ‘marsquakes’  — and whatever waves the lander’s instruments will pick up might help scientists gain unprecedented insights about Mars’ interior, from its crust to its very core. This is the first mission to Mars dedicated to studying the planet’s interior.

Like earthquakes, marsquakes are vibrations of the ground. However, while an earthquake is produced by the movement of tectonic plates, scientists believe that marsquakes occur when the planet cools and contracts, causing the crust to ruck up slightly. Scientists believe that all planetary bodies experience quakes, ranging from those that vibrate fast to those that rumble low. In the 1970s, NASA’s Viking lander tried to measure quakes on Mars but its instruments weren’t sensitive enough. However, during the Apollo missions, seismometers measured thousands of tiny quakes on the moon.

InSight will also help scientist come to a better understanding of how the solar system formed and evolved. Both Mars and Earth are rocky planets that had lots of water on their surface during their rich history. However, the two planets look very differently today — Earth is wet and teeming with life while Mars is barren and dead.

So now that InSight safely landed on Mars, what’s next? Right now, NASA engineers are busy deploying the probe’s array of solar panels so it can start generating energy as soon as possible. Over the next couple of days, NASA will perform checkouts to ensure that everything is in tip-top shape, then it will deploy the scientific instruments. It’s the first time that NASA will use a robotic arm to deploy instruments on the surface of Mars, among them the precious seismometer and a heat flow probe. Immediately, NASA will start recording data about temperature, wind, and other atmospheric parameters but it will take at least three months before there will be any seismic data. That’s because NASA wants to make sure that the instruments are properly set up and calibrated. Expect interesting new science about Mars via Insight beginning with March 2019.

Mars render.

NASA’s next mission to Mars will map the planet’s interior, scheduled for May 5th

NASA’s next mission will provide InSight into the workings of Mars’ interior — and find out whether there is such a thing as a Marsquake.

Mars render.

Mars rendered in Autodesk Maya.
Image credits Kevin Gill / Flickr.

No, that’s not a typo — NASA’s InSight mission, short for Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport, leaves little room for doubt as to what it will entail — except that it will do it on Mars. There’s a lot of interest among planetary scientists about what secrets the red planet’s interior hides, and the mission aims to bring many of those to light. As part of this mission, the eponymous lander will blast off from the Vandenberg Air Force Base in California as early as May 5, according to a news release.

Red to the core?

The InSight mission will be the first in many regards: it’s the first launch to another planet from the West Coast — usually, that’s a role reserved for Cape Canaveral, Florida. It’s also the first mission dedicated to studying Mars’ deep interior, the product of 25 years of planning and effort, says the mission’s lead investigator Bruce Banerdt.

Although the launch is scheduled for the 5th of May, it will still take the lander about six months to make the 301-million-mile treck to Mars, according to NASA estimates. Another 2-3 months will be needed to get the instruments all nicely calibrated and humming at peak accuracy; all in all, the mission should last about two Earth years, which is a little over one Martian year.

According to Banerdt, InSight will collect seismic data and chart heat flows beneath the planet’s crust, all while keeping a highly-accurate eye on Mars’ north pole. He’s confident that by the mission’s end, researchers will have enough data on hand to map out the interior structure of Mars — a feat that could finally tell us what turned the planet so barren. The craft will be beaming data back since day one, however, so maybe we’ll piece things together a bit faster.

InSight’s observations extend farther than Mars alone, though. Data gleaned from the lander will help scientists better understand how rocky bodies or planets form and evolve; Banerdt described the mission as a “scientific time machine that will bring back information about the early stages of Mars’ formation four-and-a-half-billion years ago”.

Having access to this story will even help scientists better understand how Earth and our moon came to be. Down here, because our planet is still keeping active (isn’t it making us all so proud?), the same clues InSight will be looking for just aren’t available anymore; they’ve been destroyed by millions of years of erosion, mantle convection, plate tectonics, and other geological processes. Mars, luckily for us, hasn’t been active enough to cover up the traces left by its formation and early processes, according to Banerdt.

“What InSight is going to do is, it is going to sort of fill in the last big hole in our understanding of Mars. We’ve sent orbiters to Mars which have studied the entire surface, [but e]verything more than just a few feet below the surface is completely unknown territory,” he explains.

“And InSight is going to fill in the gap in our knowledge of Mars and sort of finish the reconnaissance of the exploration of Mars.”

InSight’s launch is scheduled for May 5; if anything should interfere with that date and the mission needs to be delayed, its launch window is open until June 8.