Delays on two high-profile launches have been announced. SpaceX's (News - Alert) first Falcon 9/Dragon launch under its NASA COTS demonstration contract has slipped to Thursday, Dec. 9, at the earliest, while the last flight of space shuttle Discovery has been pushed back to February at the earliest.

In a press conference earlier this morning, SpaceX said the engine nozzle on the Falcon 9's second stage might have a problem and the company is currently taking a closer look at it. If the nozzle has to be replaced, SpaceX would attempt a launch on Friday or Saturday. Should the Falcon 9/Dragon launch not clear the pad, the company would have to reschedule for a future date.

SpaceX's latest delay is the latest in a series of hiccups the company has run into with the Falcon 9/Dragon demonstration flight. The flight was initially penciled for late October before aiming to early November. The early November date was pushed back to December due to conflicts with the launch attempt for space shuttle Discovery and for more some engineering review time with the Dragon capsule.

Even last week's static engine test of the Falcon 9 launcher didn't go quite as planned. An initial attempt on Dec. 3, to run a two-second "hot" engine test with all engines firing on the bolted-down Falcon 9, ended up at an abort at T-1.1 seconds. Two more attempts on Dec. 4, resulted in the third one yielding successful.

But Falcon 9/Dragon's hiccups are nothing compared to space shuttle Discovery's woes. The last flight of OV-130 was originally scheduled to take place on Nov. 3, but was first pushed back to Nov. 7, then late November and into early December due to a series of technically problems. The most serious problem, external cracks on two "stringers" of the shuttle's external tank, have now put the next shuttle launch attempt into early February. While the U-shaped aluminum brackets have been fixed, managers want to conduct more detailed test and analysis before signing off on a launch.

As a result, the delay will also push back the last official flight of the space shuttle program to no earlier than April.

How all these delays will ultimately affect resupply of the International Space Station is unclear. The first COTS resupply by SpaceX and/or Orbital is not likely to happen before the end of 2011 while a last-shot contingency flight of space shuttle Atlantis now might not be possible until the fall of 2011, given the push backs of the last official on-the-books shuttle flights.