Normally you don’t want dust to get into your spacecraft. That was certainly true for the InSight mission to Mars, until it died. Now, however, it’s acting as a dust collector, and Mars Reconnaissance Orbiter (MRO) scientists couldn’t be happier.
The High Resolution Imaging Science Experiment (HiRISE) onboard MRO monitors and images the surface. In particular, it has been imaging landing sites on Mars to track dust accumulation on the surface. The idea is to see how quickly the landers and their nearby environments get covered. It doesn’t just focus on landing sites, though. It also checks places like impact craters to track surface changes in and around those regions. As you can see from its latest image above, taken on April 1st, 2024, it’s getting tough to spot the InSIGHT lander thanks to ever-growing accumulations of dust.
HiRISE has been checking in on the InSIGHT lander ever since it first deployed on Mars. Early images show the hardware in fairly good detail right after landing. Then, over time, as Martian winds take their toll, it’s obvious the spacecraft is getting coated in dust. That’s also true of other spacecraft that HiRISE images from time to time.
The best image of the InSight lander taken by HiRISE in 2019. HiRISE scientists were looking for dust devil tracks and other changes in the surface due to dust. Credit: NASA/JPL-Caltech/UArizona
Why care about dust? Although we know a great deal about Mars, there’s still a lot to figure out. Wind deposition of dust is part of the so-called aeolian processes that alter the Martian surface appearance. They’re named after the Greek wind god Aeolus. Dust storms are certainly visible on Mars from Earth, but we can’t really “see” their deposits easily without getting close to (or on) the planet. Other activities, such as dust devils, also redistribute dust around the planet. All this activity creates wind streaks, sand, and dust deposits, and covers up spacecraft on the surface.
The study of the aeolian process is one of the HiRISE instrument’s major science themes. There’s not much water action to change the surface. Nor is there any Martian volcanic activity to muck up the landscape. Impact craters do tear up the surface, but they aren’t frequent. That leaves aeolian activity as a major player in Mars surface changes. Image after image shows dunes, ripples, wind streaks, dust devil tracks, and other features created by the winds. The HiRISE imaging project gives a “wide-angle” view of aeolian effects on the Red Planet and how its various surface units change over time.
The InSight lander performed almost flawlessly during its four years in operation on Mars. Although one of its instruments, the “mole” had some difficulties performing its digging action, the mission as a whole was quite successful. The seismograph monitored Marsquakes throughout the mission, which gives details about the Martian interior. It also differentiated between quakes from Mars’s interior and those caused by impacts. The spacecraft other instruments sampled the remnants of the weak magnetic field and monitored the Martian weather.
The InSight lander not only measured seismic motions on Mars, but also sampled the atmosphere and listened to its winds. Courtesy: NASA/JPL.As increasing levels of dust covered InSight’s solar panels, mission scientists had to power down many of its systems. The seismometer was the last one to be shut off. The spacecraft was officially considered “dead” after mission controllers didn’t hear from it after two attempts at communication. The last time anybody heard from it was December 15, 2022.
These days, although the instruments are silent and the solar panels are dead, the spacecraft is passively and rapidly accumulating dust. That gives scientists a chance to understand just how the surface changes thanks to aeolian activity.
Revisiting InSight
Aeolian Themes for HiRISE
Winds of Mars
InSight Mission Ends
