A launch Saturday would lead to docking Sunday, November 27, for the Dragon to deliver important research, crew supplies and hardware to the crew aboard the orbiting laboratory. Docking coverage will begin at 6 a.m. with the spacecraft planned to arrive at the space station around 7:30 a.m. Just 10 minutes before the 3:54 p.m. EST liftoff, the countdown continued. Fueling of the Falcon 9 second stage had already begun. The next steps were to chill the Falcon 9’s engines to condition them for launch, run the prelaunch checks on the flight computer, and then bring the rocket’s propellant tanks to flight pressure. SpaceX had given a “go for launch.” Then shortly before liftoff, mission managers scrubbed the launch due to poor weather conditions in the area of NASA’s Kennedy Space Center in Florida. The rocket due to launch is the SpaceX Falcon 9, a two-stage vehicle topped by the company’s uncrewed Dragon spacecraft. The first stage of the Falcon 9 is powered by nine Merlin engines that ignite at T-0. The rocket’s second stage has a single Merlin engine that takes over after separation of the first stage. Merlin engines run on a combination of cryogenic liquid oxygen and a refined kerosene fuel called RP-1. Installed atop the rocket, the cargo Dragon spacecraft is loaded with cargo bound for the International Space Station. The Dragon offers a pressurized section as well as an unpressurized “trunk” section for additional cargo. Loaded about the trunk is the next pair of ISS Roll Out Solar Arrays (iROSAs). Also located in the trunk are the spacecraft’s own power-producing solar arrays.
