SpaceX rolled the second Falcon 9 rocket to its seaside Florida launch pad and pumped propellant into the booster's fuel tanks Wednesday in a preflight countdown rehearsal.

The second Falcon 9 rocket's first stage inside the hangar at pad 40. Credit: SpaceX

A team of launch controllers powered up the two-stage rocket and filled it with kerosene and liquid oxygen propellants Wednesday afternoon, accomplishing a key exercise of the rocket and SpaceX engineers.

The test occurred on pad 40 at Cape Canaveral.

SpaceX has reserved Oct. 23 on the Air Force's Eastern Range for the Falcon 9 to blast off on its second flight. Its payload is the first functional Dragon capsule, which will make between one and three circuits around Earth and splash down in the Pacific Ocean off the coast of California.

A SpaceX spokesperson said Wednesday's wet dress rehearsal was successful.

The company plans another practice countdown soon that will culminate in a brief ignition of the Falcon's nine Merlin first stage engines, but the spokesperson did not respond to questions on its schedule.

In the months leading up to the Falcon 9's debut flight in June, SpaceX conducted two tanking exercises in February and April. A short engine test firing occurred in March.

Next month's launch will be the first time the Dragon spacecraft will fly free in orbit. An instrumented Dragon qualification unit launched June 4 on the Falcon 9's first flight, but it stayed attached to the rocket's second stage.

SpaceX is developing the Dragon to haul supplies to the International Space Station beginning next year, partially replacing the cargo transportation duties of the space shuttle after its retirement.

Orbital Sciences Corp. is working on a robotic freighter named Cygnus, which is slated for its first flight by the end of 2011.