HOUSTON — Though tentatively targeted for early January, the NASA-sponsored Space Exploration Technologies Inc. (SpaceX) cargo resupply demonstration mission of the Falcon 9 and Dragon spacecraft to the International Space Station could slip a little later into the new year.

“I think January is pretty aggressive,” Alan Lindenmoyer, manager of NASA’s Commercial Orbital Transportation Services (COTS) program, said following presentations on the status of the six-year-old cargo initiative before the American Astronautical Society national conference here Nov. 15. “At the end of this month, we will know better.”

Nonetheless, 2012 promises to be a year for major strides by SpaceX and Orbital Sciences Corp., representatives from the two COTS participants told the aerospace gathering.

During the SpaceX demonstration mission, the Dragon spacecraft will attempt to rendezvous with the space station, allowing the U.S. crewmembers to grapple and berth the supply craft using Canadarm2.

The mission’s timing will depend on the outcome of NASA’s SpaceX flight software assessments to identify potential hazards posed by two Orbcomm data-relay satellites carried by the Falcon 9 as secondary payloads and possible impingements of Dragon thruster firings on the station’s outstretched solar panels, Lindenmoyer says.

In addition, NASA intends to brief its Russian partners on the SpaceX mission strategy before signing off on the flight, according to Bill Gerstenmaier, NASA’s associate administrator for human exploration and operations.

Plans for a January liftoff from Cape Canaveral AFS are subject to change depending on the software test results and outcome of discussions with Russia, Gerstenmaier said from Moscow, where he was following the Nov. 16 docking of the Soyuz TMA-22 crew with the space station.

Meanwhile, Orbital Sciences is preparing for a late February/early March flight test of the Taurus II/Cygnus rocket and cargo carrier from the Mid-Atlantic Regional Spaceport at the Wallops Flight Facility in Virginia, says Frank Culbertson, Orbital’s senior vice president and deputy general manager.

Orbital’s commercial cargo carrier could be ready for a rendezvous and berthing demonstration flight as soon as late April, Culbertson says.