With the retirement of the space shuttles last year, NASA turned to the private sector to develop and fly freight to the station and is looking to do the same for crew transportation.

“Every time they have a successful mission, that gives the non-believers one more opportunity to get onboard and root for us and help us make this thing happen,” Bolden said.

Unlike the Russian, European and Japanese freighters that service the station, Dragon is designed to return to Earth intact, rather than burn up in the atmosphere, so it can bring back research and equipment from the station. That return capability has been missing since the shuttle’s retirement.

Dragon is scheduled to depart the station on Oct. 28 and to splash down into the Pacific Ocean off the coast of California.

SpaceX has a separate NASA contract to upgrade its Dragon capsule to carry humans as well. Boeing and privately owned Sierra Nevada also have NASA backing for space taxi design work.

In addition to SpaceX, NASA has also hired Orbital Sciences to fly cargo to the station. Orbital’s Antares rocket is expected to make a debut flight later this year.