International Space Station Supply Run By Orbital ATK Delayed

Orbital ATK, one of NASA's prime shippers, was supposed to return its Antares rocket to flight this month after a nearly two-year grounding.

This Tuesday May 31, 2016 image from video provided by NASA shows an Orbital ATK full-power test of the upgraded Antares medium-class rocket using new RD-181 engines at the at Virginia Space's Mid-Atlantic Regional Spaceport at NASA Wallops Island Test Flight Facility in Wallops Island, Va. (NASA via AP)
This Tuesday May 31, 2016 image from video provided by NASA shows an Orbital ATK full-power test of the upgraded Antares medium-class rocket using new RD-181 engines at the at Virginia Space's Mid-Atlantic Regional Spaceport at NASA Wallops Island Test Flight Facility in Wallops Island, Va. (NASA via AP)

A space station supply run by a Virginia company has slipped to September.

Orbital ATK, one of NASA's prime shippers, was supposed to return its Antares rocket to flight this month after a nearly two-year grounding. But on Wednesday, the company delayed liftoff of the retooled, unmanned rocket until mid-September.

This Tuesday May 31, 2016 image from video provided by NASA shows an Orbital ATK full-power test of the upgraded Antares medium-class rocket using new RD-181 engines at the at Virginia Space's Mid-Atlantic Regional Spaceport at NASA Wallops Island Test Flight Facility in Wallops Island, Va. (NASA via AP)This Tuesday May 31, 2016 image from video provided by NASA shows an Orbital ATK full-power test of the upgraded Antares medium-class rocket using new RD-181 engines at the at Virginia Space's Mid-Atlantic Regional Spaceport at NASA Wallops Island Test Flight Facility in Wallops Island, Va. (NASA via AP)

Antares flights have been on hold since an October 2014 launch explosion at Wallops Island, Virginia. Orbital ATK says it needs more time to inspect and test the rocket. The company also has to fit into the International Space Station schedule.

Orbital ATK used another company's rocket from Cape Canaveral, Florida, to fulfill its obligations to NASA, following the Antares accident. But now the company wants to get back on track at Wallops.

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