NASA's unmanned spacecraft OSIRIS-REx entered the orbit of asteroid Bennu on Monday. The feat set two new records, as Bennu became the smallest space object to be circled by a human-made spacecraft and OSIRIS-REx reached the lowest orbit of a space object by a human spacecraft.

OSIRIS-REx is the first-ever US mission designed to explore an asteroid and return a sample of its dust back to Earth. Bennu measures about 1,600 feet (500 meters) in diameter and is located some 70 million miles (110 million kilometers) from Earth.

The spaceship left Cape Canaveral, Florida two years ago and arrived at Bennu's location on December 3, 2018. After closely studying the asteroid for several weeks, OSIRIS-REx entered Bennu's orbit on New Year's Eve, at approximately a mile from its center.

Each orbit around the asteroid is expected to take 62 hours and OSIRIS-REx will be flying around Bennu through mid-February 2019. The spacecraft will map the asteroid in high resolution during this time.

"Entering orbit around Bennu is an amazing accomplishment that our team has been planning for years," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson.

NASA described OSIRIS-REx's orbit around Bennu as "a leap for humankind," because no spacecraft has ever "circled so close to such a small space object — one with barely enough gravity to keep a vehicle in a stable orbit."

By 2020, OSIRIS-Rex is expected to touch the asteroid with its robotic arm and collect approximately two ounces (60 grams) of material from Bennu's surface. The spacecraft will then return to Earth in 2023.

Bennu was chosen from some 500,000 asteroids in the solar system because it orbits close to Earth's path around the Sun, is the right size for scientific study, and is one of the oldest asteroids known to NASA.

Scientists are hoping the OSIRIS-Rex mission to Bennu will help uncover more about the early formation of the solar system, as well as how to find precious resources like metals and water in asteroids.