On Wednesday, December 19, 2018, NASA’s InSight lander deployed its first instrument — the Seismic Experiment for Interior Structure (SEIS) — onto the surface of Mars.
NASA’s InSight lander placed its seismometer on Mars on December 19, 2018. Image credit: NASA / JPL-Caltech.
“Seismometer deployment is as important as landing InSight on Mars,” said InSight principal investigator Dr. Bruce Banerdt, from NASA’s Jet Propulsion Laboratory.
“SEIS is the highest-priority instrument on InSight. We need it in order to complete about three-quarters of our science objectives.”
The instrument was gently placed onto the ground directly in front of the lander, about as far away as the arm can reach — 5.367 feet (1.636 m) away.
It will allow scientists to peer into the Martian interior by studying ground motion — also known as marsquakes.
Each marsquake acts as a kind of flashbulb that illuminates the structure of the planet’s interior. By analyzing how seismic waves pass through the layers of the planet, scientists can deduce the depth and composition of these layers.
“Having the seismometer on the ground is like holding a phone up to your ear,” said Dr. Philippe Lognonne, principal investigator of SEIS from Institut de Physique du Globe de Paris and Paris Diderot University.
“We’re thrilled that we’re now in the best position to listen to all the seismic waves from below Mars’ surface and from its deep interior.”
In the coming days, the InSight team will work on leveling SEIS, which is sitting on ground that is tilted 2 to 3 degrees.
The first seismometer science data should begin to flow back to Earth after the instrument is in the right position.
“InSight’s timetable of activities on Mars has gone better than we hoped,” said InSight project manager Dr. Tom Hoffman, also from NASA’s Jet Propulsion Laboratory.
“Getting the seismometer safely on the ground is an awesome Christmas present.”
