The launch of a SpaceX Falcon 9 rocket carrying a Dragon cargo ship loaded with crew supplies and science gear bound for the International Space Station — along with Christmas presents for the lab's crew — was called off Wednesday due to dangerously high upper-level winds.
SpaceX engineers planned to set up for a second launch try at 12:29:23 p.m. ET Thursday, when forecasters expect an 80 percent chance of favorable ground weather and more benign winds aloft.
As usual with most Falcon 9 launches, SpaceX plans to attempt recovery of the rocket's first stage, with landing on a company droneship stationed in the Atlantic Ocean about 210 miles east of Jacksonville, Florida.
Two minutes after the first stage touches down, the Dragon cargo ship will be released from the second stage, kicking off a three-day rendezvous with the space station.
Included in the Dragon's science cargo are eight beefed-up, genetically engineered "mighty mice," subjects of an experiment with 40 rodents to learn more about the loss of muscle and bone mass in weightlessness; a study sponsored by beer maker Anheuser Busch to study the germination of barley in space; and an advanced combustion experiment to shed more light on how flames propagate in microgravity.
"This particular Dragon will carry a little more than 2,100 pounds of science payload, including the external cargo that will be going to the orbiting laboratory," said Bryan Dansberry, assistant program scientist for NASA's International Space Station Program Science Office.
"When the Dragon splashes down about a month later in the Pacific Ocean, it'll be bringing home ... roughly 1,800 pounds of science samples and other material. By my count, this mission will enable 38 investigations, 23 of them new investigations across a wide range of science and technology areas. And when it returns it'll be bringing back samples and material from about 54 investigations."
The day after the Dragon's launch, the Russians plan to launch another cargo ship -- Progress MS-13/74P -- loaded with several tons of propellant, supplies and equipment. Liftoff from the Baikonur Cosmodrome in Kazakhstan is targeted for 4:34 a.m. Friday (12:34 p.m. local time).
With the Progress on its way, the Dragon spacecraft will pull up to within about 30 feet of the lab complex early Sunday and then stand by while Italian astronaut Luca Parmitano, operating the spacelab's robot arm, locks onto a grapple fixture.
From there, flight controllers at the Johnson Space Center in Houston will remotely operate the arm to pull the Dragon in for berthing at the Earth-facing port of the forward Harmony module. The Progress, meanwhile, is scheduled to dock at the Russian Pirs module early Monday.