The launch team at Cape Canaveral Air Force Station in Florida continues working through its steps methodically as we tick toward a liftoff at 4:10 p.m. of the SpaceX Falcon 9 and Dragon spacecraft. Thirty minutes to go before the latest cargo flight to the International Space Station commences.
At Space Launch Complex 40, where the Falcon and Dragon stand ready for space, the cryogenic liquid oxygen tanks continue to be topped off as small portions of the super-cold propellant evaporate during the last minutes of the countdown. The Merlin engines mix liquid oxygen with refined kerosene to generate the thrust needed to lift the rocket and its payload about 250 miles into space at a speed of about 17,500 mph to meet the station.