WASHINGTON — For the eighth time ever, humanity has achieved one of the toughest tasks in the solar system: landing a spacecraft on Mars.
The InSight lander, operated by NASA and built by scientists in the United States, France, and Germany, touched down in the vast, red expanse of Mars’ Elysium Planitia just before 3 p.m. Monday
There it will operate for the next two Earth years, deploying a seismometer, a heat sensor, and radio antenna to probe the red planet’s interior. Scientists hope that InSight will uncover signs of tectonic activity and clues about the planet’s past. Those findings could illuminate how Mars became the desolate desert world we see today.
Mission control at the Jet Propulsion Laboratory in Pasadena, Calif., erupted in applause, hugs, and tears as soon as the lander touched down.
‘‘That was awesome,’’ one woman said, wiping her eyes and clasping her colleague’s hand. A few minutes later, a splotchy red and brown image appeared on the control room’s main screen — InSight’s first photograph from its new home.
The interminable stretch from the moment a spacecraft hits the Martian atmosphere to the second it touches down on the rusty surface is what scientists call ‘‘the seven minutes of terror.’’
Because it takes that time for light signals to travel 100 million miles to Earth, scientists have no control over the process. All they can do is program the spacecraft with their best technology and wait. More than half of all missions don’t make it safely to the surface.
The tension was palpable Monday at JPL, where InSight was built and will be operated. At watch parties around the globe — NASA’s headquarters in Washington, the Nasdaq tower in Times Square, the grand hall of the Museum of Sciences and Industry in Paris, a public library in Haines, Alaska — legs jiggled and fingers were crossed as minutes ticked toward the landing.
At about 11:47 a.m., engineers received a signal indicating InSight had entered the Martian atmosphere. The spacecraft plummeted to the planet’s surface at a pace of 12,300 miles per hour. Within two minutes, the friction roasted InSight’s heat shield to a blistering 2,700 degrees. In another two minutes, a supersonic parachute deployed to help slow down the spacecraft. Radar was powered on.
From there, the most critical descent checklist unfolded at a rapid clip: 15 seconds to separate the heat shield. Ten seconds to deploy the legs. Activate the radar. Jettison the back shell. Fire the retrorockets. Orient for landing.
At 12:01 p.m., scientists heard a tiny X-band radio beep — a signal that InSight is active and functioning.
The mission’s objective is to determine what Mars is made of and how it has changed since it formed 4 billion years ago. The results could help solve the mystery of how the planet became a dry, desolate world.
“What we would like to understand is what is the geology, what is the interior of Mars like, how different it is from Earth,’’ said Avi Loeb, chairman of the astronomy department at Harvard University.
Martin Finucane of Globe staff contributed to this report.
