Video: Next International Space Station crew in Star City

SpaceX test-fired a Falcon 9 rocket Wednesday afternoon at NASA’s Kennedy Space Center in Florida, clearing a major hurdle before it launches Saturday night — weather permitting — with a four-person crew heading for the International Space Station.

Running two days later after a last-minute abort Sunday, a Russian Progress resupply and refueling freighter lifted off in a blanket of fog Tuesday from the Baikonur Cosmodrome to deliver three tons of cargo, propellant and water to the International Space Station.

Launch of a Russian Soyuz spacecraft Friday carrying three fresh crew members to the International Space Station will boost the lab’s crew back to six and, most important from NASA’s perspective, dramatically boost research with four crew members — three NASA astronauts and a veteran European flier — available to operate experiments in the American segment of the laboratory.