Four new craters on Mars’ surface were discovered by an international team of researchers with NASA’s InSight mission. The team calculated and confirmed the impact locations using data from a seismometer and images from the Mars Reconnaissance Orbiter. This is the first time researchers have been able to capture the dynamics of a Mars impact. The findings of the researchers were published in the journal Nature Geoscience.
“Meteoroids and other projectiles in space can change the atmosphere and surface of any planet through impact,” said co-author and University of Maryland Geology Associate Professor Nicholas Schmerr. “We’ve seen this on Earth, where these objects can hurtle through the atmosphere, strike the ground, and leave a crater. However, we’ve never been able to simulate the dynamics of an impact on Mars, where the atmosphere is much thinner.”
Studying how impacts work on Mars is like opening a window into the fundamental processes of how terrestrial planets form. All inner solar system planets share this commonality, including Earth.Nicholas Schmerr
When space projectiles enter the planetary atmosphere and collide with the ground, they produce acoustic and seismic waves (sound waves that travel through fluid or gas) (waves that travel through a solid medium). Schmerr and his colleagues on InSight used these waves, which were measured by the SEIS (Seismic Experiment for Interior Structure) instrument on InSight, to estimate the approximate locations of the resulting impact sites while observing the unique physics that dictated the projectiles’ movements. The team then compared their approximations to high-resolution camera visuals, confirming the locations and accuracy of the team’s modeling.
These findings show how planetary seismology (the study of earthquakes and related events such as volcanic eruptions) can be used to identify seismic activity sources. This capability, according to Schmerr, may aid researchers in determining how frequently new impacts occur in the inner solar system, where both Mars and Earth reside – an observation critical to understanding the population of near-Earth objects such as asteroids or rock fragments that may pose a threat to Earth.
Additionally, using images to determine the precise location of these impacts makes their associated acoustic and seismic waves invaluable for studying the Martian atmosphere and interior. With a better understanding of marsquake locations, scientists will be able to gather essential information about the planet, such as the size and solidity of its core or its heating processes.
Geophysicists like Schmerr anticipate that new advances in planetary seismology will allow them to better investigate underlying tectonic activities and other sources of seismic activity within Mars. The findings ultimately bring researchers another step closer to understanding planetary formation and evolution.
“Studying how impacts work on Mars is like opening a window into the fundamental processes of how terrestrial planets form,” Schmerr said. “All inner solar system planets share this commonality, including Earth.”
NASA’s InSight is a robotic lander designed to study the interior structure of Mars. Active since 2018, the lander is expected to continue the InSight mission until its ability to gather solar power is fully depleted.