NASA’s Martian mole successfully captured what is likely the first-ever recorded tremor on the red planet, and it sounds eerily peaceful.
The Mars lander Insight put out the French-built seismometer, Seismic Experiment for Interior Structure, or SEIS, in December on the Martian surface. On April 6, SEIS picked up a quiet signal that appeared to be coming from inside the planet, according to NASA.
A quake of this intensity wouldn’t have registered on Earth, according to the French space agency, Centre National d’Études Spatiales, or CNES, but because there is almost no excess noise on Mars, the extremely sensitive sensors picked up the tremor.
Unfortunately, “the seismic event was too small to provide useful data on the Martian interior, which is one of InSight's main objectives, according to CNES, the agency that provided SEIS.
What InSight’s teams can compare the tremors to are those measured on the moon by Apollo astronauts between 1969 and 1972, which revealed the moon is still geologically active. Insight’s team members believe the same is true for Mars.
"We've been collecting background noise up until now, but this first event officially kicks off a new field: Martian seismology,” InSight principal investigator Bruce Banerdt said.
Three weaker seismic signals were also detected March 14, April 10 and April 11, according to NASA.
Scientists are still examining the data to determine the exact cause of the signals detected.
The detection of the soft tremble was a major accomplishment in engineering and an international collaboration, according to the CNES news release.
While the SEIS instrument was provided for by CNES, InSight’s Marsquake Service team, led by the Swiss Federal Institute of Technology, identified the tremors.
On Earth, seismometers can be placed underground to better detect quakes without interference but SEIS is on the Mars surface and gets help from a protective shield built by NASA’s Jet Propulsion Laboratory to block wind and extreme temperature changes.
Unlike earthquakes, which happen on faults created by the motion of tectonic plates, Mars and the moon do not have tectonic plates. According to NASA, Mars tremors are caused by the process of cooling that, over time, creates stress on the planet’s interior until it is strong enough to break the crust.
Associate Administrator of the NASA Science Mission Directorate Thomas Zurbuchen said this is the first step in a new field of study on "Marsquakes."
This is just the beginning for InSight and its sensitive seismometer.
“We are delighted about this first achievement and are eager to make many similar measurements with SEIS in the years to come,” Charles Yana, SEIS mission operations manager at CNES said.
InSight has also gifted us other first “sounds” form the Martian surface.
On Tuesday CNES, JPL and NASA released the greatest hits of the first Mars sounds, including peculiar noises made by Martian wind, the “likely Marsquake” and noises from the lander’s robotic arm moving.