Orbital Sciences' second Commercial Resupply Services Mission, Orb-2, to the International Space Station will launch Sunday. NASA's Orb-2 launch live stream begins at noon and the launch is scheduled for 12:52 p.m. EDT.
Orbital Sciences completed its first CRS mission, Orb-1, on Jan. 12. The mission was delayed twice, rescheduled from Jan. 7 due to cold weather and again Jan. 8 due to space weather caused by an X-class solar flare. The most recent ISS resupply mission was carried out by SpaceX on Easter Sunday. The Dragon spacecraft delivered 2.5 tons of cargo and science experiments to the space station.
The Cygnus spacecraft will be launched by an Antares rocket and will carry 3,293 pounds of supplies and experiments to the space station. Crew supplies, such as care packages and food, make up the bulk of the cargo at 1,684 pounds. Cygnus will carry 783 pounds of vehicle hardware and 721 pounds of science investigations, including several CubeSats.
Some of the science experiments include the Planet Labs' Flock 1b which consists of 28 CubeSats and will capture images of Earth. The TechEdSat-4 investigation will focus on ways to return small samples. According to NASA, TechEdSat-4's "primary objectives are to further develop a tension-based drag device, or “Exo-Brake,” and demonstrate frequent uplink/downlink control capabilities. Engineers believe exo-brakes eventually will enable small samples return from the station or other orbital platforms to Earth."
Launching on Sunday, Cygnus will arrive at the Space Station Wednesday. The spacecraft will attach to the Harmony Module and NASA's Steve Swanson, Expedition 40 Commander, and ESA astronaut Alexander Gerst will grapple Cygnus using the Canadarm2. The capture process begins at 5:15 a.m. EDT on Wednesday and installation begins at 8:30 a.m. EDT, notes NASA. Cygnus will spend a month attached to the space station and will return to Earth with close to 3,000 pounds of trash.
The Orb-2 launch live stream can be viewed below.