SpaceX Reports Problem With Dragon Capsule

Update at 12 p.m. ET: SpaceX Reports Thruster Pods Fixed

SpaceX founder and CEO Elon Musk says that at least two of the Dragon capsule's four thrusters were up and running and that engineers were working on the other two, which experienced problems earlier.

"Attempting bring up of thruster pods 2 and 4," Musk tweeted shortly after he reported that the deployment of the capsule's solar array had been successful.

Here is our original post:

The unmanned SpaceX mission to resupply the International Space Station has encountered a problem, the founder of the private space firm, Elon Musk, has announced via Twitter.

"Issue with Dragon [capsule] thruster pods. System inhibiting three of four from initializing. About to command inhibit override," Musk tweeted shortly after an otherwise successful launch of the Dragon capsule, which is carrying about a ton of supplies to the ISS.

Musk is monitoring the flight from SpaceX Mission Control in California, according to The Associated Press.

The AP reports, "the trouble cropped up nine minutes after Friday's launch from Cape Canaveral."

Update at 11:45 a.m. ET: Cargo Includes Parts For Air Purifiers, Computers

"Much-needed equipment for air purifiers" is aboard the Dragon, along with fresh fruit, seeds of a flowering weed used for research, mouse stem cells, protein crystals, astronaut meals and clothing, trash bags ... computer parts and other gear," the AP says.

Dragon's 2,300-pound payload was set to reach the space station on Saturday.

It's the first major problem with a Dragon capsule since the private, California-based Space Exploration Technologies began launches of the vehicle last year. The two previous missions went without a hitch.

SpaceX has a billion-dollar contract with NASA to resupply the ISS, and the company plans for astronauts to ride the Dragon into orbit within a few years.

The news follows what NASA described earlier as a "beautiful liftoff" of the Falcon 9 launch vehicle that carries the Dragon capsule.