After seven months of traveling through space, the NASA InSight mission has landed on Mars. A few minutes after landing, InSight sent the official "beep" to NASA to signal that it was alive and well, including a photo of the Martian surface where it landed.
Mission Control at NASA's Jet Propulsion Laboratory exploded into celebratory applause and cheers after the touchdown was confirmed. The landing was watched around the world and even broadcast live on the Nasdaq Stock Market tower in New York City's Times Square.
During a post-landing NASA press conference, the astronauts on the International Space Station called down to congratulate the mission team and said they "got some goosebumps" watching the coverage.
"Today, we successfully landed on Mars for the eighth time in human history," NASA Administrator Jim Bridenstine said. "InSight will study the interior of Mars and will teach us valuable science as we prepare to send astronauts to the Moon and later to Mars. This accomplishment represents the ingenuity of America and our international partners, and it serves as a testament to the dedication and perseverance of our team. The best of NASA is yet to come, and it is coming soon."
Bridenstine said that Vice President Mike Pence called to congratulate the entire team.
InSight, or Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is going to explore a part of Mars that we know the least about: its deep interior. It launched May 5. InSight will spend two years investigating the interior where the building blocks below the planet's surface recorded its history.
To reach Mars, InSight cruised 301,223,981 miles at a top speed of 6,200 miles per hour in space, followed by two cube satellites. The suitcase-size spacecraft, called MarCO, are the first cube satellites to fly into deep space. MarCO shared data about InSight when it entered the Martian atmosphere for the landing.
"We've studied Mars from orbit and from the surface since 1965, learning about its weather, atmosphere, geology and surface chemistry," said Lori Glaze, acting director of the Planetary Science Division in NASA's Science Mission Directorate. "Now we finally will explore inside Mars and deepen our understanding of our terrestrial neighbor as NASA prepares to send human explorers deeper into the solar system."
The first image taken by InSight includes the dust cover still on the lens, which will be removed this week. The black specks are dust, and there's a rock in the left foreground. To the right is one footpad of the lander.
InSight robotically guided itself through the landing. The landing itself is a tricky maneuver. NASA engineers don't call it "seven minutes of terror" for nothing. In less time than it takes to hard-boil an egg, InSight slowed from 12,300 mph to 5 mph before it gently landed on the surface of Mars, according to NASA.
"While most of the country was enjoying Thanksgiving with their family and friends, the InSight team was busy making the final preparations for Monday's landing," said Tom Hoffman of JPL, InSight's project manager. "Landing on Mars is difficult and takes a lot of personal sacrifices, such as missing the traditional Thanksgiving, but making InSight successful is well worth the extraordinary effort."
Only 40% of missions sent to the Red Planet by any agency have been successful. Part of this is due to the thin Martian atmosphere, which is only 1% of Earth's, so there's nothing to slow something trying to land on the surface.
Like the Phoenix spacecraft, InSight had a parachute and retro rockets to slow its descent through the atmosphere, and three legs suspended from the lander absorbed the shock of touching down on the surface.
But the engineers prepared the spacecraft to land during a dust storm if need be.
About 20 minutes before landing, InSight separated from the cruise stage that helped bring it all the way to Mars and turned to position itself for entering the atmosphere.
At 2:47 p.m. ET, the entry, descent and landing phase began, and InSight came blazing into the atmosphere at 12,300 mph. Peak heating of the protective heat shield reached 2,700 degrees Fahrenheit two minutes later. This is when the intense heat caused a temporary drop in the radio signal from the craft.
Then, the parachute deployed, the craft separated from the heat shield, deployed its three legs and activated radar to sense how far it is from the ground. After getting that radar signal, it separated from the remaining shell and parachute, firing its descent engines known as retrorockets to help slow it down even more.
In ballet-like fashion, InSight executed a gravity turn to make sure the lander was in the right position before touching down. It slowed until it reached a consistent 5 mph. Then, it touched down at 2:54 p.m. ET.
Just before 3 p.m. ET, InSight sent a signal to let scientists on Earth know that it's alive and well.
"We hit the Martian atmosphere at 12,300 mph, and the whole sequence to touching down on the surface took only 6½ minutes," Hoffman said. "During that short span of time, InSight had to autonomously perform dozens of operations and do them flawlessly -- and by all indications, that is exactly what our spacecraft did."
Bruce Banerdt of JPL, InSight's principal investigator, said, "It's taken more than a decade to bring InSight from a concept to a spacecraft approaching Mars -- and even longer since I was first inspired to try to undertake this kind of mission. But even after landing, we'll need to be patient for the science to begin."
What happens next
InSight's two-year science mission won't begin right away. It will take two to three months for the robotic arm to place the mission's instruments on the surface. Meanwhile, mission scientists will photograph what can be seen from the lander's perspective and monitor the environment. Science data isn't expected until March.
Later Monday, mission scientists should be able to confirm that the spacecraft's solar arrays have unfurled.
"We are solar-powered, so getting the arrays out and operating is a big deal," Hoffman said. "With the arrays providing the energy, we need to start the cool science operations. We are well on our way to thoroughly investigate what's inside of Mars for the very first time."
InSight landed at Elysium Planitia, called "the biggest parking lot on Mars" by astronomers. Because it won't be roving over the surface, the landing site was an important determination. This spot is open, flat, safe and boring, which is what the scientists want for a stationary two-year mission.
InSight will unfurl its solar panels and robotic arm and study the entire planet from its parking spot. It's along the Martian equator, bright and warm enough to power the lander's solar array year-round.
The suite of geophysical instruments on InSight sounds like a doctor's bag, giving Mars its first "checkup" since it formed. Together, those instruments will take measurements of Mars' vital signs, like its pulse, temperature and reflexes -- which translates to internal activity like seismology and the planet's wobble as the sun and its moons tug on Mars.
These instruments include the Seismic Experiment for Interior Structures to investigate what causes the seismic waves on Mars the Heat Flow and Physical Properties Package to burrow beneath the surface and determine heat flowing out of the planet and the Rotation and Interior Structure Experiment to use radios to study the planet's core.
"Landing was thrilling, but I'm looking forward to the drilling," Banerdt said. "When the first images come down, our engineering and science teams will hit the ground running, beginning to plan where to deploy our science instruments. Within two or three months, the arm will deploy the mission's main science instruments, the Seismic Experiment for Interior Structure (SEIS) and Heat Flow and Physical Properties Package (HP3) instruments."
Meanwhile, the mission for MarCO has ended. But it proves that cube satellites can survive the trek into deep space.
"Every Mars landing is daunting, but now with InSight safely on the surface, we get to do a unique kind of science on Mars," JPL director Michael Watkins said. "The experimental MarCO CubeSats have also opened a new door to smaller planetary spacecraft. The success of these two unique missions is a tribute to the hundreds of talented engineers and scientists who put their genius and labor into making this a great day."