WASHINGTON — Orbital Sciences Corp. plans to launch its first commercially contracted cargo delivery mission to the international space station Jan. 9 following a one-day delay that was prompted by concerns about solar radiation.
The team operating Orbital’s Antares rocket and Cygnus space capsule postponed the scheduled Jan. 8 launch attempt “to spend the day further examining the potential effects of the space radiation on the rocket’s avionics suite,” the Dulles, Va., company said in a statement posted on its website that day.
In a subsequent statement, which also followed a media conference call in which Orbital said it was undecided about when it would make its next launch attempt, the company said it had settled on Jan. 9. “Upon a deeper examination of the current space weather environment, Orbital’s engineering team, in consultation with NASA, has determined that the risk to launch success is within acceptable limits established at the outset of the Antares program,” the company said.
The launch, from the Mid Atlantic Regional Spaceport at NASA’s Wallops Flight Facility on Wallops Island, Va., is slated for 1:07 Eastern time, Orbital said. This would permit the cargo-laden Cygnus capsule to rendezvous with the space station early on Jan. 12, the company said.
“This is not a frequent situation,” Antonio Elias, Orbital’s chief technical officer, said during the Jan. 8 conference call. “We will make a decision later today as to whether to press for launch tomorrow, or wait until the sun gets a little quieter.”
If Orbital is unable to get the launch off Jan. 9 it could be looking at several days of additional delay. The terrestrial weather forecast for Jan. 10 calls for heavy cloud cover, which means a 70 percent chance of another scrub, according to Frank Culbertson, vice president and general manager of Orbital’s Advanced Programs group.
If the launch slips beyond Jan. 10, there is a chance of an even longer delay, Culbertson said. That is because a sensitive science payload now packed up in Cygnus might have to be unpacked and reset if it cannot be delivered to the station soon, he said.
The impending launch is the first of eight Orbital owes NASA under a $1.9 billion Commercial Resupply Services contract signed in 2008. It was supposed to happen Jan. 7, but was pushed back because of the arctic air mass that swept across the East Coast, punishing Wallops with freezing temperatures.
If NASA’s original schedule had held up, Orbital would have launched the mission already. Liftoff was originally scheduled for late December, but the flight was delayed so the space station crew could perform two spacewalks to fix a faulty ammonia pump that caused the outpost’s cooling system to malfunction prior to the winter holidays.
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