After two failed contact attempts, NASA has decided to retire the InSight Mars mission after four years of service.
Mission controllers at the agency’s Jet Propulsion Laboratory (JPL) in Southern California were unable to contact the Mars mission after two consecutive attempts. Due to this, they concluded that the spacecraft’s solar-powered batteries have run out of energy – a state engineers refer to as a ‘dead bus.’
Previously, NASA had decided to bid farewell to the mission if it missed two communication attempts, hence why the Mars mission has now been retired. They will continue to listen for a signal, just in case, but hearing from it at this point is considered unlikely.
“I watched the launch and landing of this mission, and while saying goodbye to a spacecraft is always sad, the fascinating science InSight conducted is cause for celebration,” said Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate in Washington.
“The seismic data alone from NASA’s Discovery Program mission offers tremendous insights – not just into Mars – but other rocky bodies, including Earth.”
What was the Mars mission?
The InSight Mars mission set out to study the deeper interior of Mars. The lander data has yielded details about the planet’s interior layers, the surprisingly strong remnants beneath the surface of its extinct magnetic dynamo, weather on the planet, and lots of quake and seismic activity.
Its highly sensitive seismometer, along with daily monitoring performed by the French Space Agency and the Marsquake Service, detected 1,319 marsquakes. These included quakes caused by meteorite impacts, the largest of which unearthed boulder-size chunks of ice late last year.
Impacts from the Mars mission helped scientists determine the age of the planet’s surface, and data from the seismometer provides scientists a way to study the planet’s crust, mantle, and core.
“With InSight, seismology was the focus of a mission beyond Earth for the first time since the Apollo missions, when astronauts brought seismometers to the Moon,” explained Philippe Lognonné of Institut de Physique du Globe de Paris, principal investigator of InSight’s seismometer.
“We broke new ground, and our science team can be proud of all that we’ve learned along the way.”
The seismometer was the last science instrument that remained powered on, as dust accumulating on the lander’s solar panels gradually reduced its energy, a process that began before NASA extended the Mars mission earlier this year.
A lasting legacy
Laurie Leshin, Director of JPL, which manages the mission, stated: “InSight has more than lived up to its name. As a scientist who’s spent a career studying Mars, it’s been a thrill to see what the lander has achieved, thanks to an entire team of people across the globe who helped make this mission a success.
“Yes, it’s sad to say goodbye, but InSight’s legacy will live on, informing and inspiring future missions.”
All Mars missions face challenges, with InSight being no different. The lander featured a self-hammering spike, that was intended to dig 15 metres down and trail a sensor-laden tether to measure the heat within the planet. This would have enabled scientists to calculate how much energy was left over from Mars’ formation.
Designed for the loose, sandy soil that was seen on other missions, the spike could not gain traction in the unexpectedly clumpy soil around InSight. The instrument, which was produced by the German Aerospace Center (DLR), was eventually buried just slightly below the surface, collecting valuable data on the physical and thermal properties of the Martian soil along the way. This is useful for any future human or robotic missions that attempt to dig underground.
The Mars mission buried the spike to the extent possible, thanks to engineers at JPL and DLR using the lander’s robotic arm in inventive ways. Primarily intended to set science instruments on the Martian surface, the arm and its small scoop also helped to remove dust from InSight’s solar panels as power began to diminish.
Counterintuitively, the mission determined that they could sprinkle dirt from the scoop onto the panels during windy days, allowing the failing granules to gently sweep dust off the panels.
Bruce Banerdt of JPL, the mission’s principal investigator, concluded: “We’ve thought of InSight as our friend and colleague on Mars for the past four years, so it’s hard to say goodbye. But it has earned its richly deserved retirement.”
JPL manages InSight for NASA’s Science Mission Directorate. InSight is part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.
