Mars lander InSight’s power diminishing fast, end of mission in sight?

InSight, which has hit headlines this week with the realtime recording of sound from the Mars when meteoroids struck Mars’ surface at four places since its landing on the Red Planet in November 2018, is nearing the end of its mission by mid-2023.

The first NASA mission to explore Mars’ deep interior, InSight rover landed on Mars surface on Nov. 26, 2018, in the Elysium Planitia region and collected enormous data over the past four years.

To its credit, the lander has detected more than 1,300 marsquakes since touching down on Mars, providing information that has allowed scientists to measure the depth and composition of Mars’ crust, mantle, and core.

As power on the spacecraft diminishes, the InSight team hopes to maximize the science and increase the possibility of recording additional marsquakes.

However, the lander achieved a milestone when NASA released the sound of a meteoroid striking Mars that was captured by its Reconnaissance Orbiter’s High Resolution Imaging Science Experiment (HiRISE) camera. The sound resembled like a “bloop” due to a peculiar atmospheric effect and the sound can be heard three times.

In addition, the InSight lander has provided visuals of three craters created between 2020 and 2021, ranging between 53 and 180 miles (85 and 290 kilometers) at Elysium Planitia.

It has proved a point that Mars has escaped from many such meteoroids as its atmosphere is just 1 per cent as thick as Earth’s, and several meteoroids pass through it without disintegrating, according to NASA. InSight’s team also said other impacts may have been obscured by noise from wind or by seasonal changes in the atmosphere.

The data helps NASA scientists to know the impact rate and estimate the age of different surfaces by counting its impact craters. The more they find, the older is the surface.

Auto shutdown of seismometer deferred

Initially, the lander was to automatically shut down the seismometer, its last operational science instrument by the end of June in order to conserve energy, surviving on what power its dust-laden solar panels can generate until around December.

Now, the team plans to program the lander to keep the seismometer operate three more months though batteries get discharged sooner and cause the spacecraft to run out of power soon. The team hopes that it might enable the seismometer to detect additional marsquakes.

“InSight hasn’t finished teaching us about Mars yet,” said Lori Glaze, director of NASA’s Planetary Science Division in Washington. “We’re going to get every last bit of science we can before the lander concludes operations.”

This collage shows three other meteoroid impacts that were detected by the seismometer on NASA’s InSight lander and captured by the agency’s Mars Reconnaissance Orbiter using its HiRISE camera. / NASA/JPL

As of September 10, 2022, InSight was generating an average of 420 watt-hours of energy per Martian day, or sol. The tau, or level of dust cover in the atmosphere, was estimated at .80 (typical tau levels outside of dust season range from 0.6-0.7).

All instruments but the seismometer have already been powered down. Like other Mars spacecraft, InSight has a fault protection system that automatically triggers “safe mode” in threatening situations and shuts down all but its most essential functions, allowing engineers to assess the situation. Low power and temperatures beyond pre-determined limits can trigger safe mode.

Seisomometer helps detect more Marsquakes

To enable the seismometer to continue to run for as long as possible, the mission team is turning off InSight’s fault protection system. While this will enable the instrument to operate longer, it leaves the lander unprotected from sudden, unexpected events that ground controllers wouldn’t have time to respond to.

“The goal is to get scientific data all the way to the point where InSight can’t operate at all, rather than conserve energy and operate the lander with no science benefit,” said Chuck Scott, InSight’s project manager at NASA’s Jet Propulsion Laboratory in Southern California.