After three delays, Orbital Science Corporation’s Antares launch system has successfully completed its first test mission: delivering a dummy Cygnus supply capsule into orbit. Designed primarily to ferry supplies to the International Space Station (ISS), the success of the Antares mission leads to more opportunities for commercial space travel.
NASA retired its space shuttles in 2011 and it has been contracting with the Russians as well as private firms to deliver both cargo and astronauts to the space station. Other rockets have preceded Antares, most notably SpaceX’s Dragon, but the Antares’ Cygnus capsule is larger and can carry more cargo. When the first real supply capsule is launched, it will carry two tons of supplies to the ISS in one shot.
The Antares rocket itself is a combination of existing rocket technologies. Its liquid-fueled first stage takes its cue from the Soviet Zenit rocket, while the second stage is provided by ATK, the same contractor that built the rocket boosters for NASA’s space shuttles. Orbital has successfully integrated these systems with its own Modular Avionics Control Hardware.
The Antares rocket’s first stage burns for four minutes as it carries the spacecraft to an altitude of 70 miles. At this point, its fuel supply is depleted, and the burned out first stage is dropped while the rocket continues on for another 93 seconds on its second stage. The Cygnus capsule has its own power, propulsion and navigation systems, as well as a pressurized cargo compartment, with capabilities that are very similar to Dragon.
Orbital has one more test flight planned under its contract with NASA before it begins to deliver real cargo to the ISS. After the next successful test flight, Orbital is contracted to launch eight payloads to the ISS by 2016. If all goes well, the first delivery mission will begin in late June.
Via New Scientist