Another space lander on Mars has reached the end of its mission. NASA abandons the InSight project because it is losing power due to the dust accumulated on its solar panels. The agency has stated that it will continue to use the probe’s seismometer to record earthquakes until the current is exhausted. For this reason, flight controllers will monitor InSight until the end of this year before abandoning it definitively.
“There is no sadness in the team. We are still focused on the operation of the spacecraft” said Bruce Banerdt, the principal scientist at the Jet Propulsion Laboratory (JPL). Since landing on Mars in 2018, InSight has detected more than 1,300 earthquakes. The largest ever recorded, with a magnitude of 5, occurred just two weeks ago. With InSight, NASA abandons its second project on the Red Planet. A global dust storm had already put Opportunity out of commission in 2018. In the case of InSight, it was simply a matter of dust accumulation, particularly in greater quantities in the last year.
The InSight mission
The primary purpose of the lander was to study the morphology and geological evolution of Mars (ref.). InSight has provided a lot of information in this field. By studying the internal structure and composition of rocks, it has been possible to understand how the Red Planet was formed and structured. Other instruments on board the lander worked to measure the rate of Martian tectonic activity and the impact of meteorites.
Another goal of InSight was to study the geology in three layers of Mars: crust, mantle, and core. Scientists have discovered that the crust is slightly thinner than expected, ranging from 25 to 40 km. The upper layer of the crust is about 10 kilometers thick and less dense than the lower crust. Core of Mars is molten and considerably larger than expected, with a radius of about 1,800 kilometers. The data have helped explain how Mars’ core can still be molten despite having cooled considerably since its formation.
InSight also monitored the upper mantle using seismic waves that travel through depths of about 800 kilometers before returning to the surface. The strong and cold outer shell, the lithosphere, is about 500 kilometers thick, above a relatively cold mantle compared to Earth’s mantle. Determining the composition and structure of the layers and the rate at which heat filters from them has helped us better understand the geological history of the Martian surface.
New ideas on propulsion
The other two functioning NASA spacecraft on the Martian surface, Curiosity and Perseverance, are still working perfectly, thanks to the use of atomic energy. This difference with InSight has led to a rethink of the use of photovoltaics for future missions to Mars. Planetary science director Lori Glaze has emphasized that, as an alternative to atomic energy, new technology should be tested for cleaning panels before this type of power becomes standard.
The lander is currently generating one-tenth of the power it receives from the sun. Deputy project manager Kathya Zamora Garcia stated that initially it had enough energy to operate an electric oven for an hour and 40 minutes. Now, we are down to 10 minutes. The team had anticipated the accumulation of dust but hoped that a gust of wind could clean the solar panels. This has yet to happen after 1235 Sols (Martian days), despite several thousand dust devils brushing past the lander. “None of them hit us hard enough to blow the dust off the panels” Banerdt told reporters.