After more than a decade of work and much anticipation, the University of Arizona-led OSIRIS-REx mission will swipe a sample from the asteroid Bennu's rocky surface on Oct. 20 from the Nightingale sample site.

The mission team successfully completed a first rehearsal last month, and on Tuesday, NASA approved a second rehearsal date of Aug. 11 and the Touch-and-Go, or TAG, sample collection event in October.

The original target date for sample collection was planned for late August, but the new Oct. 20 date will allow the team more time to prepare, in the wake of the COVID-19 pandemic.

"From the project's inception, and from experience on previous missions, the principal investigator, Dante Lauretta, myself and the team laid out a methodical schedule with strategically placed schedule margin with the knowledge that we need to accommodate unexpected events along the way," said Heather Enos, deputy principal investigator for the OSIRIS-REx mission. "The fact that this is such a long mission means there's more opportunity to experience the unexpected. We knew that and planned for it. I'm in awe of how adaptable this team is."

OSIRIS-REx has three major partners: Lockheed Martin, NASA's Goddard Space Flight Center and the University of Arizona. They're currently using remote communications, Enos said, but for big operations, such as rehearsal and sample collection, there is a lot of value in having your team in one location.

After the first rehearsal on April 14, the team decided to schedule more time between the second rehearsal and sample collection.

"We want to provide the team more time to see if there's anything we can to do improve the mission's probability of success," Enos said. "We gave them two more weeks between rehearsal and sample collection. We were expecting a 25-meter (about 80-foot) target radius, but we quickly learned that Bennu's rocky surface would only allow for two to four meters (less than 14 feet) to work with."

The OSIRIS-REx spacecraft arrived at the asteroid Bennu in December 2018 and has since been surveying and studying the asteroid from orbit. The mission is scheduled to leave Bennu in March 2021 and return to Earth on Sept. 24, 2023.