An Atlas V rocket just successfully launched NASA’s OSIRIS-REx vehicle into space from Cape Canaveral, Florida, initiating the spacecraft’s journey to grab a sample from an asteroid and bring it back to Earth. The probe’s expedition isn’t exactly a short one, though. It will take OSIRIS-REx seven years to rendezvous with the asteroid, scoop up a small sample of materials off the space rock, and then return back to our planet. If all goes according to plan, it'll be the first time NASA brings back pieces of an asteroid, allowing researchers to closely study the chemical makeup of Bennu in laboratories here on Earth.

OSIRIS-REx is now on its way into a heliocentric orbit. In two weeks, NASA will turn all the spacecraft's instruments on to see if they're working properly. Then it's smooth sailing for OSIRIS-REx, as it spends the next year traveling around the Sun. The spacecraft will eventually swing back by Earth in September 2017 and use the planet’s gravity to change the plane of its orbit, putting it in the same plane as Bennu. Then it’s another year of traveling through space until OSIRIS-REx reaches the asteroid in August 2018.

That’s when the spacecraft’s mapping campaign begins. OSIRIS-REx will scout out the best place to grab a sample off of Bennu’s surface. And in July 2020, it will attempt to grab up to 60 grams (two ounces) of asteroid material with its TAGSAM — a small robotic arm with a sampling device attached at the end. In a process that takes just five seconds, the spacecraft will extend the robotic arm toward Bennu and gently tap the asteroid with the sampling device. Then the TAGSAM will release a burst of nitrogen gas, causing any loose material on Bennu to shoot up into the sampling device.

After it grabs its sample, OSIRIS-REx is slated to head back to Earth in March 2021, arriving in September 2023. But only a portion of the spacecraft will make it back to solid ground. A container carrying the asteroid sample will separate from the rest of OSIRIS-REx and land on Earth with the help of a parachute. The rest of OSIRIS-REx will stay in space and continue on an orbit around the Sun. However, NASA does have the option to use the spacecraft for future missions.

If the sample survives that trip to Earth, it will be the largest amount of materials to come back from space since the Apollo era. NASA researchers will spend two years cataloging and analyzing the particles in the sample, hoping to better understand the chemical components of Bennu. That could tell us a lot about the chemicals that made up the early Solar System and whether or not the building blocks for life came to Earth on early asteroids. However, the biggest findings from the sample may not occur for some time. NASA plans to set aside 75 percent of the sample at NASA’s Johnson Space Flight Center in Houston. That way future generations of scientists can analyze these space rocks, once more robust analysis techniques are invented.