NASA’s latest Mars lander, InSight, successfully touched down on the surface of the Red Planet this afternoon, surviving an intense plunge through the Martian atmosphere. It marks the eighth picture-perfect landing on Mars for NASA, adding to the space agency’s impressive track record of putting spacecraft on the planet. And now, InSight’s two-year mission has begun, one that entails listening for Marsquakes to learn about the world’s interior.
After six and a half months of traveling through space, InSight hit the top of Mars’ atmosphere a little before 3PM ET. It then made a daring descent to the surface, performing a complex multistep routine that slowed the lander from more than 12,000 miles per hour to just 5 miles per hour before it hit the ground. To get to the surface safely, InSight had to autonomously deploy a supersonic parachute, gather radar measurements, and ignite its thrusters all at the right time. Altogether, the landing took just under seven minutes to complete, prompting the nickname “seven minutes of terror.”
During the plunge, two tiny spacecraft above Mars gathered data of the entire event. The pair of probes are known as the MarCO satellites, and they actually launched in May with InSight from California. The two satellites are modified CubeSats, a type of standardized spacecraft made out of 10-centimeter cubes. They’ve been traveling to Mars on their own ever since launch, making them the first CubeSats to ever go into deep space.
The MarCO satellites flew over the Red Planet as InSight performed its landing, coming within 2,175 miles of the surface. InSight sent out multiple signals during its fall that the MarCO satellites received, deciphered, and then sent back to Earth. That gave NASA engineers an almost real-time understanding of how each step in the landing process occurred.
Then, once InSight made it to the surface, the lander sent out an initial signal to Earth announcing its safe arrival. Seven minutes later, the spacecraft used an even more powerful radio to send a bigger signal, verifying the earlier alert, and sending NASA more details about its status. A few minutes later, InSight sent back its very first picture from the Martian surface, showing the terrain that it had landed on.
NASA engineers in mission control applauded as each update from the landing occurred. Toward the end, a flight controller listed off the descending altitude of InSight until confirmation came that it had landed on the surface. When that happened, mission control exploded into cheers and applause as the InSight celebrated a successful landing after many years of preparation.
There’s still more data about the landing that’s coming NASA’s way. The space agency’s Mars Reconnaissance Orbiter, which is in orbit around Mars, observed the entire event from space and will send that information to Earth in about three hours. InSight also has to unfurl its solar panels, which are crucial for powering the spacecraft while it’s on Mars. Without the panels, the mission doesn’t happen. NASA’s Mars Odyssey — which is already in orbit around Mars — will fly over InSight to see what’s going on with the panels and then let NASA know in five and a half hours.
Once that confirmation occurs, InSight’s mission can get underway in earnest. While on the surface of Mars, InSight will stay very still so that it can measure the tiny wobbles of the planet during Marsquakes, using the sound waves from these events to figure out what the planet’s interior is made of. Over the next two to three months, InSight will use a robotic arm to deploy its primary two instruments: a seismometer and a self-hammering nail. The seismometer will listen for the quakes, while the nail will drill almost 16 feet underneath the crust to measure Mars’ internal temperature.
In the months ahead, InSight should uncover a deeper knowledge of Mars’ interior than we’ve ever had before.