SpaceX has been getting ready for its first mission to the international space station for months now. SpaceX is going to be the first private spacecraft to dock with the ISS after receiving the green light from NASA for a scheduled launch on April 30. The flight readiness review was approved at the Johnson Space Center this week.
With the approval given and the mission scheduled SpaceX is on track to be the first commercial carrier to deliver a payload to the international space station. Cargo is frequently delivered to the ISS using Russian Soyuz capsules. This initial mission will have nothing aboard the Dragon capsule. However, SpaceX designed the Dragon capsule to hold up to seven passengers or cargo.
In the future SpaceX many be contracted to ferry astronauts to and from the ISS rather than astronauts hitching a ride on the Soyuz capsule. It will take about four days before the Dragon docks with the space station once it's in orbit. Dragon will remain attached to the ISS for 18 days. The days prior to docking with the station will be used for demonstration tests, including a flight around the space station to test and verify maneuverability, navigation, communication capability among other tests. SpaceX points out that success isn't guaranteed with this mission and there's a lot that can go wrong. There is a chance that the mission can be aborted at any of the testing points prior to the actual docking.