Scientists Puzzled by Sudden, Super-Loud Rumble Inside Mars
Frank Landymore
Wed, October 18, 2023
Captain Shook
In May of last year, NASA's Insight Mars lander detected an enormous seismic tremor reverberating just below the planet's surface. At a magnitude 4.7, it's the most powerful ever detected on the Red Planet — and indeed anywhere off world.
Ever since, the puzzling "marsquake" has had scientists scrambling for an explanation. Mars has long been considered a geologically "dead" planet, meaning there are few signs of volcanic activity, let alone of the kinds that would rattle the planet like that.
Initially, the most likely explanation scientists put forward was that the reverberations could have been caused by a meteoroid impact.
But a new study, published in the journal Geophysical Research Letters, found that after months of scouring the planet's surface, no evidence of a fresh impact has been discovered — meaning the tremendous tremor came from deep within the planet.
"We didn't find a crater," lead author Benjamin Fernando at the University of Oxford, told Scientific American, "which strongly suggests this event was tectonic."
Stressed Out
It would be a hard impact to miss. Anything large enough to send out a record-shattering marsquake after smashing into the surface would blow open a crater hundreds of feet in diameter. That points to some sort of tectonic activity as being the culprit, and adds to an emerging body evidence that Mars' deceased status is dead wrong.
"We still think that Mars doesn't have any active plate tectonics today, so this event was likely caused by the release of stress within Mars' crust," Fernando said in a statement about the work. "These stresses are the result of billions of years of evolution; including the cooling and shrinking of different parts of the planet at different rates."
Most of the data gathered about Mars' seismic activity so far indicates that it's originating from a huge pair of trenches known as the Cerberus Fossae, which are believed to be the open wounds of an underlying fault where magma interactions could still persist.
Insight's data on the monster marsquake, however, pinpoints the source of its reverberations as far beyond the faults, to the planet's southeast. It appears that some other mysterious phenomenon is behind the almighty tremor, and for now, scientists will have to see what shakes out.
"Clearly there's a massive piece of the tectonic and seismic puzzle that we haven't yet unraveled," Fernando told SA.
More on Mars: Amazing Video Soars Over Mars' Epic "Labyrinth of Night"
Laura Baisas
Tue, October 17, 2023
An artist's illustration of a cutaway of Mars along with the paths of seismic waves from two separate quakes in 2021. These seismic waves, detected by NASA’s InSight mission, were the first ever identified to enter another planet’s core.
A giant seismic event on Mars—a “marsquake”—that shook the Red Planet last year had an unexpected source, surprising astrophysicists from around the world. They suspected a meteorite strike. Instead, enormous tectonic forces within Mars’s crust, which caused vibrations that lasted for six hours, caused the quake and not a meteorite strike. The findings are described in a study published October 17 in the journal Geophysical Research Letters.
[Related: Two NASA missions combined forces to analyze a new kind of marsquake.]
NASA’s InSight lander recorded the magnitude 4.7 marsquake on May 4, 2022, which scientists named S1222a. Its seismic signal was similar to those of previous quakes that were caused by meteorite impacts, so the team began to search for an impact crater.
In the new study, a team from the University of Oxford worked with the European Space Agency, Chinese National Space Agency, the Indian Space Research Organisation, and the United Arab Emirates Space Agency to scour more than 55 million square miles on Mars. Each group examined the data coming from its own satellites to look for a crater, dust cloud, or other signature of a meteorite impact. Because the search came up empty, they now believe that S1222a was caused by the release of huge tectonic forces from within the Martian interior.
That doesn’t mean Mars’s tectonic plates are moving the way they do during an earthquake. The best available evidence suggests the planet is remaining still. “We still think that Mars doesn’t have any active plate tectonics today, so this event was likely caused by the release of stress within Mars’ crust,” study co-author and University of Oxford planetary geophysicist Benjamin Fernando said in a statement. “These stresses are the result of billions of years of evolution; including the cooling and shrinking of different parts of the planet at different rates.”
While Fernando explains that scientists do not fully understand why some parts of Mars seem to have more stress than others, these results can help them investigate further. “One day, this information may help us to understand where it would be safe for humans to live on Mars and where you might want to avoid!” he said.
This spectrogram shows the largest quake ever detected on another planet. Estimated at magnitude 5, this quake was discovered by NASA's InSight lander on May 4, 2022. CREDIT: NASA/JPL-Caltech/ETH Zurich.
S1222a was one of the last events recorded by NASA’s InSight mission before its end. The InSight lander launched in May 2018 and survived “seven minutes of terror” to touch down on Mars, where it studied the planet’s interior and seismology for years. The last of the spacecraft’s data was returned in December 2022, after increasing dust accumulation on its solar panels caused InSight to lose power.
[Related: InSight says goodbye with what may be its last wistful image of Mars.]
In its four years and 19 days of service, InSight recorded more than 1,300 marsquakes. At least eight of these events were from a meteorite impact; the largest two formed craters that were almost 500 feet in diameter. If the S1222a event was formed by an impact, the team estimates that the crater to be would have been at least 984 feet in diameter.
The team is applying knowledge from this study to other work, including future missions to our moon and the tectonics that are similar to California’s famed San Andreas fault located on one of Saturn’s moons named Titan. They also hope that it encourages additional major international collaborations to study the Red Planet and beyond.
“This has been a great opportunity for me to collaborate with the InSight team, as well as with individuals from other major missions dedicated to the study of Mars,” study co-author and New York University Abu Dhabi astrophysicist Dimitra Atri said in a statement. “This really is the golden age of Mars exploration!"
Mars was shaken by its strongest marsquake ever in 2022. Now we know what caused it
Sharmila Kuthunur
Tue, October 17, 2023
Artist's concept depicts NASA's InSight lander after it has deployed its instruments on the Martian surface.
The strongest-ever quake to violently shake Mars arose not because of a crashing asteroid but rather the tectonic forces within the planet itself, scientists reported on Tuesday (Oct. 17). The new findings show the Red Planet is more seismically active than previously thought.
On May 4, 2022, NASA's now-retired InSight lander recorded a magnitude 4.7 quake, five times stronger than the previous record holder of magnitude 4.2 that InSight measured in 2021. Unlike most marsquakes that cease within an hour, the reverberations from the summer quake continued for a record six hours, marking the strongest and longest quake ever recorded on another planet.
After landing in Elysium Planitia on Mars in November 2018, Insight sensed over 1,300 marsquakes, at least eight of which were traced to asteroid impacts. The signal from the massive May 2022 quake, measured by a sensitive seismometer onboard the lander, was similar to others caused by asteroid strikes, so scientists began searching for a fresh, 300-meter wide crater on Mars and a plume of dust, both of which would have appeared immediately after an asteroid impact. Teams in India, China, Europe and the United Arab Emirates searched for these indicators using their respective orbiters circling Mars, but they were never found, scientists say. That's why after months of searching, scientists concluded that the quake was tectonic in origin.
Related: Scientists hail scientific legacy of NASA's Mars InSight lander
Conventional wisdom holds that unlike Earth, Mars is too small and too cold to host tectonic processes. Earth's tectonic plates — massive, irregularly shaped rocks whose boundaries are buried beneath oceans — move in response to forces in the mantle (the layer between its crust and core) and usually lead to landslides and earthquakes. Mars' surface, however, is not broken in the same way Earth's is, so plate tectonics are not believed to occur on the Red Planet.
Related Stories:
— This may be the last Mars photo from NASA's InSight lander before it dies on the Red Planet
— NASA's InSight Mars lander spotted from orbit, covered in dust
— See a sunrise on Mars in this stunning view from NASA's InSight lander (photo)
Instead, the quake detected by InSight was likely caused by the release of billion-year-old stress within Mars' crust which formed and evolved due to various parts of the planet cooling and shrinking at different rates, according to the new study.
"We still do not fully understand why some parts of the planet seem to have higher stresses than others, but results like these help us to investigate further," Benjamin Fernando, a postdoctoral fellow at the University of Oxford in the U.K., said in a statement. "One day, this information may help us to understand where it would be safe for humans to live on Mars and where you might want to avoid!"
This research is described in a paper published Tuesday (Oct. 17) in the journal Geophysical Research Letters.
Researchers reveal source of largest ever Mars quake
Tue, October 17, 2023
Artist's concept depicts NASA's InSight lander after it has deployed its instruments on the Martian surface.
The strongest-ever quake to violently shake Mars arose not because of a crashing asteroid but rather the tectonic forces within the planet itself, scientists reported on Tuesday (Oct. 17). The new findings show the Red Planet is more seismically active than previously thought.
On May 4, 2022, NASA's now-retired InSight lander recorded a magnitude 4.7 quake, five times stronger than the previous record holder of magnitude 4.2 that InSight measured in 2021. Unlike most marsquakes that cease within an hour, the reverberations from the summer quake continued for a record six hours, marking the strongest and longest quake ever recorded on another planet.
After landing in Elysium Planitia on Mars in November 2018, Insight sensed over 1,300 marsquakes, at least eight of which were traced to asteroid impacts. The signal from the massive May 2022 quake, measured by a sensitive seismometer onboard the lander, was similar to others caused by asteroid strikes, so scientists began searching for a fresh, 300-meter wide crater on Mars and a plume of dust, both of which would have appeared immediately after an asteroid impact. Teams in India, China, Europe and the United Arab Emirates searched for these indicators using their respective orbiters circling Mars, but they were never found, scientists say. That's why after months of searching, scientists concluded that the quake was tectonic in origin.
Related: Scientists hail scientific legacy of NASA's Mars InSight lander
Conventional wisdom holds that unlike Earth, Mars is too small and too cold to host tectonic processes. Earth's tectonic plates — massive, irregularly shaped rocks whose boundaries are buried beneath oceans — move in response to forces in the mantle (the layer between its crust and core) and usually lead to landslides and earthquakes. Mars' surface, however, is not broken in the same way Earth's is, so plate tectonics are not believed to occur on the Red Planet.
Related Stories:
— This may be the last Mars photo from NASA's InSight lander before it dies on the Red Planet
— NASA's InSight Mars lander spotted from orbit, covered in dust
— See a sunrise on Mars in this stunning view from NASA's InSight lander (photo)
Instead, the quake detected by InSight was likely caused by the release of billion-year-old stress within Mars' crust which formed and evolved due to various parts of the planet cooling and shrinking at different rates, according to the new study.
"We still do not fully understand why some parts of the planet seem to have higher stresses than others, but results like these help us to investigate further," Benjamin Fernando, a postdoctoral fellow at the University of Oxford in the U.K., said in a statement. "One day, this information may help us to understand where it would be safe for humans to live on Mars and where you might want to avoid!"
This research is described in a paper published Tuesday (Oct. 17) in the journal Geophysical Research Letters.
Researchers reveal source of largest ever Mars quake
Nina Massey, PA Science Correspondent
Tue, October 17, 2023
Researchers have revealed the possible cause of the largest ever Mars quake.
A global team of scientists, led by the University of Oxford, suggest the 4.7 magnitude quake was not the result of meteorite hitting the planet, and was instead caused by enormous tectonic forces within Mars’ crust.
The event caused vibrations to reverberate through the planet for at least six hours, and was recorded by Nasa’s InSight lander on May 4 2022.
The event, dubbed S1222a, was similar to previous quakes known to be caused by meteoroid impacts, and led to an international search for a fresh crater.
Although Mars is smaller than Earth, the two planets have similar land surface areas because Mars has no oceans.
In order to survey the huge amount of ground – 144 million km2 – study lead Dr Benjamin Fernando of the University of Oxford worked with the European Space Agency, the Chinese National Space Agency, the Indian Space Research Organisation, and the United Arab Emirates Space Agency.
This is thought to be the first time that all missions in orbit around Mars have collaborated on a single project.
Each team used data from their satellites orbiting Mars to look for a new crater, or any other tell-tale signature of an impact, like a dust cloud appearing in the hours after the quake.
However, after several months of searching, the researchers have announced that no fresh crater was found.
Dr Fernando said: “We still think that Mars doesn’t have any active plate tectonics today, so this event was likely caused by the release of stress within Mars’ crust.
“These stresses are the result of billions of years of evolution; including the cooling and shrinking of different parts of the planet at different rates.
“We still do not fully understand why some parts of the planet seem to have higher stresses than others, but results like these help us to investigate further.
“One day, this information may help us to understand where it would be safe for humans to live on Mars and where you might want to avoid.”
He added: “This project represents a huge international effort to help solve the mystery of S1222a, and I am incredibly grateful to all the missions who contributed.
“I hope this project serves as a template for productive international collaborations in deep space.”
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