Mars is 33.9 million miles away from Earth. It takes months to journey between the two planets, which means all mission components have to last.
While NASA is using robotic landers and instruments to study Mars before human exploration, robots come with their fair share of problems.
On Earth, you can take your broken computer to tech support for repairs. But what does NASA do when its instruments need repairs? They certainly can’t send other robots or humans to make the repairs.
NASA’s recent repairs to the InSight lander give us a good view into the world of remote repairs. This often requires creativity and great caution, since scientists have to use instruments in untested ways.
HP3 and the InSight lander
The InSight lander has been on Mars since November 2018. The lander is designed to study Martian composition, atmosphere, and geology.
However, just a few months after landing on the Red Planet, InSight encountered an issue with one of its instruments that required repairs.
Onboard the InSight lander is the Heat Flow and Physics Properties Package (HP3) instrument. This instrument measures how heat flows from the interior of Mars to the planet’s surface.
HP3 has a probe called a “mole” that it uses to drill into the surface of Mars. The mole can burrow to depths of 16 feet below the surface, where it tests the thermal conductivity of Martian soil.
HP3’s mole was designed to drill up to 16 feet into the soil, but in February 2019, the instrument hit a snag. As the mole was coming out of its housing, it got stuck at just one foot beneath the surface.
The mole has remained there, stuck, since February, and the situation has NASA’s scientists perplexed.
Repairing HP3’s mole
In March, NASA used HP3’s heat probe to analyze the seismic activity around InSight. InSight hammered the ground and scientists used the seismometer to “listen” to the soil in hopes of solving the problem.
After looking at the data, scientists now hypothesize that there isn’t enough friction in the sandy soil underneath InSight. Without friction, the mole bounces in place and can’t drill.
But this isn’t a simple matter of moving the mole to another location. The mole wasn’t designed to be moved, and if it comes out of the ground, it can’t be used again. Instead, NASA plans to use InSight’s robotic arm to troubleshoot the mole.
However, it’s a risky move. The arm was designed to place instruments on the Martian surface, not to pick up and move other instruments.
InSight will carefully move HP3’s support structure so scientists can view the mole on InSight’s cameras. Scientists plan to move very carefully, avoiding damage to the instruments or lander itself. They plan to lift the HP3 housing in three steps over the course of a week.
NASA needs to get a better view of the situation before repairing the mole. If it’s a simple matter of giving the mole more friction, scientists say InSight’s robotic arm may be able to press on the soil’s surface, giving the mole more traction.
The bottom line
It’s taken months to troubleshoot and identify solutions for one error on the InSight lander. NASA has to be very cautious with their repairs because they only get one shot.
As far as next steps, NASA is still doing calculations and running simulations before moving the HP3 housing. It will be some time before the mole can move again.
Interstellar travel is fraught with danger for both humans and robots. Although these InSight repairs take time, they’re the perfect way to practice remote repairs as humans travel beyond the stars.