Today's launch of Orbital Sciences' Cygnus spacecraft to the International Space Station (ISS) has been scrubbed. According to NASA, thick cloud and disturbed weather at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida prohibited the liftoff of the unmanned Orbital Sciences/ATK Cygnus CRS-4 mission and launch control ordered a 24-hr postponement at 6:11 pm EST.
This is the fourth mission for the Cygnus to the ISS and the first since Orbital Sciences/ATK Cygnus CRS-3 was destroyed in the launch pad explosion of an Antares booster in 2014.
According to Orbital Sciences, the launch was originally scheduled for 5:55 pm EST and no technical difficulties were reported. However, as the afternoon progressed, the local weather deteriorated to the point where it violated safety guidelines and the launch was postponed. The new launch time has been set at 5:55 pm EST tomorrow.
Named "S.S. Deke Slayton II" after the Mercury 7 astronaut and commander of the Apollo-Soyuz mission in 1975, today's launch would have been the first for the enhanced Cygnus, which carries 53 percent more cargo weight. It's loaded with about 7,700 lb (3,500 kg) of food, clothing, crew supplies, spare parts, equipment, and science experiments for the ISS as part of Orbital Sciences' Commercial Resupply Services (CRS) contract with NASA.
The Orbital Sciences/ATK Cygnus CRS-3 mission was lost when its Antares launcher exploded on the pad on October 28, 2014 at NASA's Wallops Flight Facility. Orbital ATK says that until the Antares returns to service in 2016, future Cygnus missions will rely on the ULA Atlas V rocket.