Cygnus is on its way to the ISS

An Antares rocket, carrying a Cygnus cargo spacecraft, lifts off Wednesday from the Mid-Atlantic Regional Spaceport in Virginia, en route to the ISS. (credit: NASA/Bill Ingalls)

Orbital’s Cygnus cargo spacecraft is now on its way to becoming the second commercial cargo vehicle to service the International Space Station. The Antares rocket carrying the Cygnus cargo spacecraft lifted off on schedule at 10:58 am EDT (1458 GMT) Wednesday and placed the Cygnus spacecraft into earth orbit. The countdown and launch went well: the only concern was during a time in the countdown when it appeared that, in a worst-case scenario, a launch failure could, given atmospheric conditions, create enough overpressure that occupants of several houses were asked, if they were home. to stand outside in the event windows broke. (As it turned out, the concern subsided and, of course, there was no explosion.)

Since launch, Cygnus has been going through its paces. The spacecraft performed overnight “free drift and abort” demonstrations, the first of ten milestones for the spacecraft as it proceeds to the station, and also carried out two orbit-raising engines burns. A third thruster burn is planned for Thursday afternoon. If everything continues on schedule—something that can’t be guaranteed on a test flight, although everything has gone well so far—Cygnus will arrive at the ISS and be grappled by the station’s robotic arm as early as 7:25 am EDT (1125 GMT) Sunday.

Once there, Cygnus will remain attached to the station for 30 days before departing for a destructive reentry. The spacecraft is carrying 700 kilograms of supplies, more than any previous commercial cargo mission to the station, Orbital’s Frank Culbertson said at a post-launch press conference (a subtle dig at SpaceX’s three Dragon flights to the station.) Culbertson added Orbital would be ready to fly another Cygnus mission, the first of eight under a commercial resupply contract with NASA, as early as December, although NASA officials said they will make a decision on whether Orbital or SpaceX will fly in the December launch opportunity after this test flight.