Cygnus CRS Orb-4 (S.S. Deke Slayton II)

This is the 4th mission under NASA's Commercial Resupply Service agreement with Orbital ATK. The unmanned Cygnus cargo vessel delievered approximately 3,500 kg (7,700 lbs.) of supplies and science experiments to the International Space Station. The craft features a longer, enhanced cargo module and remained berthed to the station for 2 months.