Since NASA's InSight mission deployed its dome-shaped seismometer on the dusty surface of Mars in December, there was great hope that the Lander of Robotics would quickly discover its first Marsquake or "Marsquake". Well, the wait has finally come to an end – the mission's Seismic Experiment on Internal Structure (SEIS) confirmed its first faint rumble from the red planet confirming this Mars on April 6 (on the 128th Martian Day or Sol of Mission) seismically active.
"We have been waiting months for a signal like this," said Philippe Lognonné, SEIS team leader at the Institute for Physique du Globe in Paris (IPGP) in France, in a statement by NASA. "It's so exciting to finally have evidence that Mars is still seismically active, and we look forward to sharing detailed results as we have the opportunity to analyze them."
NASA hopes to use such seismic signals for Mars a kind of health check. Like a doctor putting a stethoscope on a patient's chest, InSight does something similar: it tries to 'hear' what's ticking the planet. On earth, the cacophony of seismic signals bouncing off our planet is distorted when they hit regions of varying density. By measuring these seismic waves, we have come to know the various unreachable layers deep underground.
The interior of Mars is a mystery; The planet does not have a global magnetic field for reasons we have not fully understood yet, and its volcanic activity was extinguished hundreds of millions of years ago. If the planet is geologically (or more accurately "isological") dead, how can it generate any Marsquakes? It is believed that the planet shrinks on cooling and crackles with small quakes that echo throughout the interior of Mars. Mission scientists also want to be aware of meteorite impacts that create their own mini-dithers, perhaps turning InSight into a real-time meteorite detector.
So far, Marsquakes have been a theoretical possibility, but now we know they are there. They can be used by InSight to understand what is below the surface of the planet.
According to mission scientists, this first Marsquake is a pipsqueak and nothing like the trembling we're used to in Southern California. On Mars, however, this weak quake is characterized by the comparative silence of the quiet innards of Mars. Other weaker seismic signals were also heard (March 1
Although the April 6 event was too weak to be informed about the Martian interior, scientists are upset because we've seen something like this – on the Moon.
"The Martian Sol 128 event is exciting because its size and longer duration correspond to the profile of lunar earthquakes discovered during the Apollo missions on the lunar surface," said Lori Glaze, director of the Planetary Science Division at NASA -Headquarters.
During the Apollo program, astronauts placed five seismometers on the lunar surface, tracking thousands of "moonquakes" between 1969 and 1977, and even helped model his formation. Although InSight is just a seismometer on Mars, scientists hope it will give us a window into the mysterious Martian interior that we know so little about.
"Initial readings from InSight continue the science that began with NASA's Apollo missions," InSight Principal Investigator Bruce Banerdt of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, said in a press release. "So far, we have collected background noise, but this first event officially opens a new field: Marseismology!"