NASA has announced that its robotic probe InSight lander had detected a quake on April 6 (the 128th Martian day) of the 2-year mission. This marks the first time a seismological tremor has been recorded on another planet other than the Earth and its moon.
The tremor originated from inside the planet, as opposed to atmospheric influences above the surface such as wind. Scientists are analysing the data to determine exactly what caused it. Three distinct types of sounds can be heard: noise from Martian wind, the quake itself and InSight’s robotic arm as it moves to take photos.
Capturing quake an engineering feat
It was measured by InSight’s seismometer known as Seismic Experiment for Interior Structure (SEIS). This instrument was lifted on to the Martian surface by the probe’s robotic arm. Incorporating low- and high-frequency sensors, SEIS is so sensitive that it can detect surface movements smaller than a hydrogen atom. CNES, the French space agency, provided the SEIS instrument to NASA.
“InSight’s first readings carry on the science that began with NASA’s Apollo missions,” said InSight principal investigator Bruce Banerdt of California’s Jet Propulsion Laboratory in a NASA press release. “We’ve been collecting background noise up until now, but this first event officially kicks off a new field: Martian seismology!”
Even though Mars doesn’t have any tectonic plates, this first seismic signal reveals that it experiences quakes. Scientists expect InSight to detect stronger tremors.
Better understanding of what’s below Mars’ surface
“We’ve been waiting months for a signal like this,” said Philippe Lognonné, SEIS team lead at the Institut de Physique du Globe de Paris in France. “It’s so exciting to finally have proof that Mars is still seismically active. We’re looking forward to sharing detailed results once we’ve had a chance to analyze them.”
“We are delighted about this first achievement and are eager to make many similar measurements with SEIS in the years to come,” said Charles Yana, SEIS mission operations manager at CNES.
The quake is tiny by Earth’s standards. Tom Pike, professor of microengineering at mission partner Imperial College London, told the ‘BBC’: “It’s probably only a Magnitude 1 to 2 event, perhaps within 100km or so. There are a lot of uncertainties on that, but that’s what it’s looking like.” Dr Bruce Banerdt, NASA’s chief scientist on the InSight mission, added: “This particular Marsquake – the first one we’ve seen – is a very, very small one. In fact, if you live in Southern California like I do, you wouldn’t even notice this one in your day-to-life. But since Mars is so quiet, this is something that we’re able to pick up with our instrument.”
InSight touched down on Mars in November 2018 to study its deep interior. The spacecraft’s range of instruments will measure the planet’s temperature, rotation and seismic activity.