The capsule originally had been set to rendezvous with the space station, which flies about 260 miles above Earth, on Sunday, Sept. 22 - a full week before it did dock with the station.
That planned rendezvous was postponed, however, after engineers discovered a data format mismatch between an onboard space station navigation system and a similar system on Cygnus. The Orbital Sciences team quickly developed and uploaded a software fix.
Once the glitch was repaired, Cygnus' rendezvous with the station was pushed to Sunday so it wouldn't interfere with arrival of three new space station crew members last Wednesday.
Cygnus is scheduled to remain attached to Harmony until Oct. 22. After that, the capsule, carrying refuse from the station, will burn up on re-entry in Earth's atmosphere.
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