Static fire tests of Dragon, the first private spacecraft to be launched to the International Space Station (ISS), has been successful, NASA reported.

“SpaceX reports that the Static Test Fire was successful,” NASA wrote in its Twitter account.

The launch, initially scheduled for April 30, was moved to May 7 to conduct additional tests of the unmanned spacecraft’s software.

The Falcon 9 rocket and Dragon capsule, manufactured by private company SpaceX, are at Cape Canaveral undergoing final preparations ahead of the launch.

SpaceX has already conducted two successful Falcon 9 launches and a demonstration flight of the Dragon capsule in December 2010. It became the first privately built and operated spacecraft to be launched to and recovered from Earth orbit.

The Dragon can carry a payload of about six metric tons to the near-earth orbit, and recover three metric tons of payload from the orbit.

Dragon was designed and built by California-based Space Exploration Technologies, known as SpaceX as part of NASA’s Commercial Orbital Transportation Services (COTS) program to encourage private companies into developing spacecrafts delivering payloads to near-earth orbit and the ISS.