OSIRIS-REx’s long-awaited 34-day launch window opens Sept. 8, shortly after 4 p.m., Arizona time. The UA-led mission is set to launch from Cape Canaveral, Florida with the goal of rendezvousing with the asteroid Bennu and retrieving a sample from its surface. 

Scientists hope Bennu, which was chosen because of its size, composition and proximity to Earth, will give insights into the solar system and the origins of life on Earth. OSIRIS-REx is the first NASA mission to collect samples from an asteroid and bring them back to Earth. 

Related: Behind the scenes of OSIRIS-REx and the team that keeps it all running.

The spacecraft will orbit the sun for a year then head toward Bennu, which it is scheduled to reach in 2018. After spending a few years surveying the surface and mapping potential sample sites, scientists will select the final site, at which OSIRIS-REx will make contact with Bennu’s surface. 

The window for departure from Bennu and the journey back to Earth will open in March 2021. The spacecraft should land September 2023, approximately two and a half years after leaving Bennu and seven years after launching from earth. 

OSIRIS-REx, which will launch aboard an Atlas V rocket has a month-long launch period due to the fact that it is launching during the middle of Florida’s hurricane season. 

Want to celebrate the launch? 

Everyone is invited to a launch party on Sept. 8 starting at 2 p.m. on the UA Mall. KAMP Student Radio will emcee the event, which will offer a live-stream of the launch, music, giveaways, trivia and guest speakers. 

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