Today, NASA introduced nine astronauts who will fly to the International Space Station (ISS) on the first flights of the Boeing and SpaceX commercial crew systems. Eight are members of the NASA astronaut corps while the ninth, Chris Ferguson (a former NASA astronaut), works for Boeing. NASA said additional crew members will be assigned later by its ISS partners.

NASA Administrator Jim Bridenstine made the announcement to an enthusiastic crowd at Johnson Space Center (JSC) in Texas. Among the dignitaries in attendance were Republican members of the Texas congressional delegation: Senator Ted Cruz and Representatives Brian Babin, John Culberson, and Pete Olson. Cruz chairs the space subcommittee of the Senate Commerce, Science, and Transportation Committee. Babin chairs the space subcommittee of the House Science, Space, and Technology Committee and represents JSC in Congress. Culberson chairs the Commerce-Justice-Science subcommittee of the House Appropriations Committee, which funds NASA. Olson and Culberson both represent districts near JSC.

The event was a celebration, not a time to talk about the launch delays for both Boeing and SpaceX revealed over the past two days. Only SpaceX President and COO Gwynne Shotwell alluded to them, thanking the members of Congress for their support and the American public for “your patience, your dedication to allowing us to finish this job. We’re not going to let you down. Ad astra.”

SpaceX’s Crew Dragon/Falcon 9 and Boeing’s CST-100 Starliner/Atlas V systems are being built as public-private partnerships with NASA. Under their contracts with NASA, both companies must launch an uncrewed test flight followed by a crewed test flight before the systems are certified for operational use. Bridenstine stressed yesterday that NASA does not set the dates. “We don’t dictate the timelines to them. They tell us what their timeline is and then we’re going to buy their service.” NASA does, however, make public the dates the companies are targeting. As of yesterday, they are:

The crews announced today are for the crewed test flights and the first post-certification flight. No dates have been made public for the post-certification flights.

Boeing CST-100 Starliner Crewed Flight Test: Eric Boe (NASA), Chris Ferguson (Boeing), Nicole Mann (NASA) Post-Certification Flight: Josh Cassada (NASA), Suni Williams (NASA)

SpaceX Crew Dragon Crewed Test Flight (“Demo-2”): Robert Behnken (NASA), Doug Hurley (NASA) Post-Certification Flight: Victor Glover (NASA), Mike Hopkins (NASA)



Both spacecraft can accommodate four astronauts. The test flights originally were expected to carry two each, but NASA revealed earlier this year that it was considering adding a third to Boeing’s with the potential of “operationalizing” that mission to deliver crew that would remain aboard the ISS. NASA said the decision was in response to a proposal from Boeing and if SpaceX made a similar proposal, the agency would consider it.

When operational, the spacecraft will ferry crews to and from ISS, a partnership among the United States, Russia, Canada, Japan, and 11 European countries operating under the aegis of the European Space Agency (ESA). Pursuant to the Intergovernmental Agreement that governs the partnership, NASA is responsible for transporting not only U.S. astronauts, but those from Canada, Japan and Europe.

Russia transports its own crews and, since 2011 when the U.S. space shuttle program was terminated, is the only partner that can send people to ISS at all. NASA pays Russia to fly U.S. and other non-Russian crew members. The point of the commercial crew program is to restore the ability to “launch American astronauts on American rockets from American soil,” an oft-used phase. Bridenstine said yesterday, however, that he expects Russians to fly on the commercial crew vehicles, too. “We are committed to our partnership with Russia on the International Space Station even after we have crew. We will be launching on Soyuz rockets, we want them to launch on commercial crew rockets.”

In a press release today, NASA said: “Additional crew members will be assigned by NASA’s international partners at a later date.”

Once the commercial crew systems are operational, it will be possible to increase the size of the crews who remain aboard ISS for long-duration (4-6 month) missions from six to seven. That was the original plan: three from Russia and four from NASA and its European, Canadian and Japanese counterparts.

The number of crew who can remain on the ISS for extended periods is limited by available resources (air, water, food, power, etc.) and the ability to evacuate them in an emergency. NASA cancelled its own plans to build “lifeboats.” The space shuttle could only remain attached to ISS for about two weeks, so for all 18 years that ISS has been permanently occupied, Soyuz has been the only available lifeboat. Thus the number of people who could remain for long duration missions is dictated by how many Soyuzes are attached. Typically there are two, setting the crew size at six.

The four-person commercial crew vehicles are designed to serve as lifeboats, so once they are operational, the standard crew size can grow to seven. That is very important because a great deal of crew time is spent maintaining the ISS rather than conducting scientific experiments, which was a primary motivation for building the ISS in the first place. The seventh crew member’s time is expected to be devoted to science. Thomas Zurbuchen, NASA Associate Administrator for NASA’s Science Mission Directorate, made that point in a tweet today.