InSight lander deposits its main sensor on the surface of Mars
After completing a 300 million mile journey in space, touching down on the Martian surface, and taking a few days' break to primp itself and snap a few selfies, NASA's InSight lander has now completed yet another important milestone by placing its seismometer on the surface of the Red Planet. The sensor will collect a great portion of the mission's scientific data and will combine with a heat probe to investigate the internal structure of Mars, even registering much of the local "weather," from dust devils to meteorite strikes.
TheSEIS instrument – short for "SeismicExperiment for Interior Structure"– is the first seismometer to be deployed to the surface of Mars inover 40 years. Its two predecessors were aboard each of the Vikinglanders (which landed in 1976), but they were unable to collectuseful data because they were housed on the landers themselves, wheretheir measurements were easily thrown off by vibrations caused bywinds and the nearby equipment.
Tocircumvent the problem, this time around NASA designed a seismometerthat could be manipulated by a mechanical arm and deposited directlyon the Martian surface. The exact spot was carefully chosen afterscientists back on Earth examined pictures of the terrain in theimmediate surroundings, within the 5-ft (1.5 m) reach of thearm. This long-awaited step was successfully completed on December19.
Inearly January, the mechanical arm will be deployed once more to placea protective cover which will shield the seismometer from wind interference. This will complete the deployment of the sensor,so that the valuable data collection may begin atlast.
"Seismometerdeployment is as important as landing InSight on Mars," saidInSight Principal Investigator Bruce Banerdt. "The seismometeris the highest-priority instrument on InSight: We need it in order tocomplete about three-quarters of our science objectives."
Specifically, SEIS will be able to register seismic waves caused by"marsquakes," the impact from meteorite strikes (NASA expects to record up to 10 of them over the course of the mission), and, because of the extreme sensitivity of the instrument, even weatherphenomena like dust devils, which are sometimes the cause ofmarsquakes.
Bylate January, the robotic arm will come to life once again to deploya second instrument – an advanced heat probe – onto the surface.The probe will slowly and autonomously dig a few meters into theground with a hammering motion. The vibrations generated by theburrowing process will then be picked up by SEIS and used to understandthe structure of the subsurface.
NASAexpects that the analysis of the seismic activity will producereliable data on the inner composition of the Red Planet, providinguseful insights into how this and other bodies in our solar systemhave formed.