Duration of NASA’s first Commercial Crew mission remains undecided

Administrator urges public to watch May 27 launch at home

When NASA astronauts Bob Behnken and Doug Hurley climb out of their SpaceX Crew Dragon capsule and onto the International Space Station later this month, the length of their stay will depend on how much wear and tear NASA measures on their capsule as it circles Earth docked to the station, NASA officials told reporters today during a series of briefings.

NASA managers initially planned for Behnken and Hurley to spend just seven days aboard ISS, but a reduced number of crew members on the station led them to plan on a longer mission of a month to 119 days. The current crew of a U.S. astronaut and two Russian cosmonauts needs Behnken and Hurley to help tend experiments and maintain the station.

If the May 27 launch schedule holds, the liftoff of the Falcon 9 with Behnken and Hurley will mark the first launch of astronauts from U.S. soil since the final space shuttle mission in 2011.

SpaceX must complete this test mission, called Demo-2, before NASA clears its Crew Dragon design to routinely carry up to seven crew members to and from the station under the Commercial Crew program. SpaceX previously flew another Dragon capsule without crew to ISS in a March 2019 demonstration.

The capsule must remain in good enough condition to bring the pair home, because there is no backup vehicle designated for them. One particular component that will be watched closely are the solar arrays that unfurl near the bottom of the spacecraft, said Steve Stich, NASA deputy manager for Commercial Crew.

“Any solar array in low-Earth orbit tends to degrade a little bit over time,” Stich said. In the case of Dragon, the cells on the solar arrays would stop generating power after about 120 days on orbit.

ISS program manager Kirk Shireman described the mission duration as a tradeoff between keeping enough crew members at the station to complete research and needed repairs, and clearing the Crew Dragon design for routine crewed flights. This can only happen after the capsule returns Behnken and Hurley safely to Earth.

“What we’d like to do from a station perspective is keep them on orbit as long as we can,” Shireman said, and then return Behnken and Hurley to Earth once SpaceX has nearly completed the first Crew Dragon for the regular operational flights to come.

SpaceX President Gwynne Shotwell told reporters that the capsule for that flight will be shipped to Kennedy Space Center, Florida, “in the next few months.” It will carry three U.S. astronauts and an astronaut from JAXA, the Japan Aerospace Exploration Agency, to the station.

In the meantime, NASA and SpaceX are exercising social distancing ahead of the Demo-2 launch by encouraging the public to watch a livestream of the event. NASA Administrator Jim Bridenstine warned that large crowds gathering for a view of the liftoff risks spreading the coronavirus, which “could cause setbacks” for Demo-2.

“The best way we can [keep the mission on time] is to do that while keeping everyone safe, and having large crowds of hundreds of thousands of people at the Kennedy Space Center is not the way to do that,” he said.