Orbital Sciences Corp.'s Cygnus capsule was supposed to arrive Sunday, four days
after its launch. But the rendezvous was aborted because of a discrepancy in navigation data between the two vessels.
The Virginia company has developed and tested a software repair to sync up the two sets of GPS data. Different formats inadvertently were used for reporting time, said company spokesman Barron Beneski. NASA's Bruce Manners, a commercial space project executive, called it a "very small, simple fix."
Despite the quick remedy, NASA and Orbital Sciences agreed Monday to delay this second delivery attempt until at least Saturday. That's because of an impending manned mission from Kazakhstan; it would have cut it too close and created too big a workload to squeeze in the Cygnus before then.
Three astronauts are scheduled to blast off on a Russian rocket Wednesday and arrive at the space station later in the day. That will round out the crew to the normal six.
This is the maiden voyage of the Cygnus and therefore considered a test flight.
Only one other private company has attempted space station shipments: Space Exploration Technologies Corp. of California, good for three deliveries over the past 1 1/2 years. SpaceX launches from Cape Canaveral, while Orbital Sciences flies from Wallops Island, Va.
NASA is contracting with the two companies to keep the 260-mile-high outpost stocked.
Manners said the Cygnus has plenty of fuel and opportunities for numerous approaches. A firm delivery date will be chosen following the Soyuz arrival late Wednesday.
Orbital Sciences Corp.: http://www.orbital.com/Antares-Cygnus/