Massive meteoroid strike on Mars creates 500-feet wide crater, unearths boulder-sized blocks of water ice
Since landing in November 2018, NASA's InSight Mars lander has studied the Red Planet's crust, mantle, and core, and even detected 1,1318 marsquakes. Due to dust settling on its solar panels, unfortunately, InSight's power has largely declined in recent months, and the spacecraft is expected to shut down, in the next six weeks.
But, before a graceful exit, InSight detected a magnitude 4 marsquake on December 24, caused by a meteoroid strike estimated to be one of the biggest seen on Mars.
InSight scientists were uncertain about the origins of the quake. That is until scientists working at Malin Space Science Systems (MSSS), which built and operates two cameras aboard the Mars Reconnaissance Orbiter (MRO), spotted a "new, yawning" crater on February 11, 2022.
"It’s unprecedented to find a fresh impact of this size," Ingrid Daubar of Brown University, who leads InSight’s Impact Science Working Group, said in a statement.
"It's about 500ft wide, or about two city blocks across, and even though meteorites are hitting the planet all the time, this crater is more than 10 times larger than the typical new craters we see forming on Mars."
There's more. Scientists also found that the explosion revealed boulder-sized blocks of water ice that were buried closer to the Martian equator. This discovery is bound to have implications for NASA's plans to send astronauts to Mars.
A significant moment in geologic history
The meteoroid is estimated to have spanned 16 to 39 feet (5 to 12 meters). "The impact, in a region called Amazonis Planitia, blasted a crater roughly 492 feet (150 meters) across and 70 feet (21 meters) deep. Some of the ejecta thrown by the impact flew as far as 23 miles (37 kilometers) away," the release said.
"The image of the impact was unlike any I had seen before, with the massive crater, the exposed ice, and the dramatic blast zone preserved in the Martian dust," said Liliya Posiolova, who leads the Orbital Science and Operations Group at MSSS, and is the author of the first study. "I couldn’t help but imagine what it must have been like to witness the impact, the atmospheric blast, and debris ejected miles downrange."
"We thought a crater this size might form somewhere on the planet once every few decades, maybe once a generation," Daubar said, during a news conference held on Thursday. "So it was very exciting to be able to witness this event, and to be lucky enough that it happened while InSight was recording seismic data — that was a real scientific gift."
Seismic surface waves detected for the first time
Even though InSight Scientists had previously observed meteorite impacts, they were small and didn't produce seismic signals; instead, they produced 'body waves' that came from underground.
The quake that happened in December and another that came from a meteor impact produced surface-level seismic waves, which were the first ever to be detected on another planet.
"This is the first-time seismic surface waves have been observed on a planet other than Earth. Not even the Apollo missions to the Moon managed it," Doyeon Kim, a geophysicist and senior research scientist at ETH Zurich's Institute of Geophysics, and lead author of the second study, said in a press release.
Seismic surface waves are imperative to know more about the planet's formation and evolution. Here, it could provide information about the structure of the Red Planet's crust.
Signs of volcanic activity - Mars is not geologically dead
Another research revealed that Mars harbored molten magma, despite claims that the planet was geologically dead. "The darker shade of the dust signifies geological evidence of more recent volcanic activity – perhaps within the past 50,000 years - relatively young, in geological terms," said Simon Stähler, senior scientist at the Institute of Geophysics, ETH Zurich, and the lead author of the paper published in the journal Nature.
The study also identified that 20 recent marsquakes originated in the Cerberus Fossae, a region consisting of a series of rifts. According to Staehler, "it is possible that what we are seeing are the last remnants of this once active volcanic region or that the magma is right now moving eastward to the next location of the eruption."
The new findings could be some of the final ones as InSight wraps up operations.
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