Planet Earth is about to receive a special delivery, the largest sample ever taken from an asteroid. NASA’s spacecraft will fly past Earth on Sunday and bring down at least a glass of debris it captured from asteroid Bennu, ending the seven-year search.

The sample capsule will parachute into the Utah desert as its mother ship, the Osiris-Rex spacecraft, moves away to rendezvous with another asteroid. Scientists expect to receive about a pound (250 grams) of rock and dust, far more than the roughly teaspoonful amount Japan brought back from two other asteroids. No other country has collected asteroid debris that preserves time capsules from the birth of our solar system that could help explain how Earth and life emerged.

Sunday’s landing ended with an encounter with carbon-rich Bennu, a unique pogo stick-style descent and sample capture, a 4 billion-mile (6.2 billion kilometer) journey highlighted by a stuck cap that sent part of the cache out. space. and now NASA’s first asteroid samples are returning.

“I ask myself how many heart-pounding moments you can experience in a lifetime, because I feel like I’m going to reach my limit,” said Dante Lauretta of the University of Arizona, the mission’s chief scientist.

A brief overview of the spacecraft and its cargo:

A LONG JOURNEY

The Osiris-Rex asteroid hunter launched a $1 billion mission in 2016. It reached Bennu in 2018 and spent the next two years flying around the small, rotating space rock, searching for the best place to take samples. Three years ago, the spacecraft suddenly touched down on the asteroid’s surface, dove in and reached out with its 10-foot (3-meter) vacuum cleaner, sucking up dust and rocks. The device pushed and gripped with such force that the stones got stuck in the edge of the lid. As the samples were launched into space, Lauretta and her team scrambled to get the rest of the material into the capsule. The exact amount inside will not be known until the container is opened.

ASTEROID BENNU

Discovered in 1999, Bennu is believed to be the remnant of a much larger asteroid that collided with another space rock. It’s about a third (half a kilometer) wide, the size of the Empire State Building, and its black, rugged surface is covered in rocks. Rolling like a gypsy, Bennu orbits the Sun once every 14 months and rotates every four hours. Scientists believe Bennu preserves the remains of a solar system that formed 4.5 billion years ago. It may come dangerously close and hit Earth on September 24, 2182, exactly 159 years after the first pieces of the asteroid arrived. Lauretta said studying Osiris-Rex closely could help him figure out how to manipulate Benna if necessary.

GAME DAY

Osiris-Rex will launch the sample capsule from a distance of 63,000 miles (100,000 kilometers) on Sunday morning, four hours before it is scheduled to land at the Utah Department of Defense Test and Training Range. The release team will come from spacecraft manufacturer Lockheed Martin’s control center in Colorado. Soon the mothership will separate and begin exploring another asteroid. The capsule, approximately 3 feet wide (81 centimeters) and 1.6 feet (50 centimeters) high, will hit the atmosphere at 27,650 mph (44,500 km/h) during the final 13 minutes of its descent. The main parachute will slow the last mile (1.6 kilometers) and allow descent at 18 km/h (11 mph). Once everything is deemed safe, the capsule will be flown by helicopter to a makeshift clean laboratory at the testing site. The next morning, the plane will transport the closed container full of debris to Houston, where NASA’s Johnson Space Center is located.

CLEAN THAN CLEAN

NASA curator Kevin Reiter said the new laboratory at Johnson will be confined to the Bennu debris to prevent cross-contamination with other collections. Building 31 currently houses moon rocks returned by Apollo astronauts from 1969 to 1972, as well as comet dust and solar wind particles collected during two previous missions, and Martian meteorites found in Antarctica. Asteroid samples will be processed in nitrogen-purged gloveboxes by personnel wearing clean clothing from head to toe. NASA is planning a high-profile reveal of Bennu’s riches on October 11.

ASTEROID FALL

NASA is calling this fall the Asteroid Fall, as three asteroid missions mark major milestones. Another asteroid hunter will be launched after Osiris-Rex lands on October 5. Both the NASA spacecraft and its metallic asteroid target are named Psyche. And in a month, NASA’s Lucy spacecraft will encounter its first asteroid after lifting off over Cape Canaveral, Florida, in 2021. On November 1, Lucy will fly past Dinkinesh in the main asteroid belt between Mars and Jupiter. This is a warm-up for Lucy’s unprecedented tour. A cluster of asteroids that orbit Jupiter around the sun, called the Trojans. Neither Psyche, nor Lucy, nor Osiris-Rex will collect souvenirs during its next mission to explore the asteroid Apophis in 2029.

OTHER SAMPLE RETURNS

This is the third sample NASA has returned from deep space, not counting the hundreds of pounds (kilograms) of moon rocks collected by the Apollo astronauts. The agency’s first robotic sampling failed in 2004. A capsule of solar wind particles crashed into the Utah desert and crashed, endangering the samples. Two years later, the American capsule carrying the comet dust landed unscathed. Japan’s first asteroid-sampling mission obtained microscopic grains from the asteroid Itokawa in 2010. A second trip in 2020 recovered about 5 grams (about a teaspoon) from the asteroid Ryugu. The Soviet Union returned lunar samples to Earth in the 1970s, and China returned lunar materials in 2020. Source