Orbital-2, also known as Orb-2, was the third flight of the Orbital Sciences'

uncrewed resupply spacecraft Cargo spacecraft are robotic spacecraft that are designed to carry cargo, possibly to support space stations' operation by transporting food, propellant and other supplies. This is different from a space probe, whose missions are to conduct scien ...

Cygnus, its third flight to the

International Space Station The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...

, and the fourth launch of the company's Antares

launch vehicle A launch vehicle or carrier rocket is a rocket designed to carry a payload (spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pad, launch pads, supported by a missile launch contro ...

. The mission launched from the Mid-Atlantic Regional Spaceport (MARS) on 13 July 2014 at 16:52:14 UTC.

Spacecraft

This was the second of eight scheduled flights by Orbital Sciences under the Commercial Resupply Services (CRS-1) contract with

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

. It was the last planned usage of the enhanced Castor 30B second stage for this CRS Orb-x series. In an Orbital Sciences tradition, the Cygnus spacecraft was named the ''S.S. Janice Voss'' after

Janice E. Voss Janice Elaine Voss (October 8, 1956 – February 6, 2012) was an American engineer and a NASA astronaut. Voss received her B.S. in engineering science from Purdue University, her M.S. in electrical engineering from MIT, and her PhD in aeronautic ...

, a NASA astronaut and Orbital employee who died on 6 February 2012.

Launch and early operations

The mission was originally scheduled to launch on 1 May 2014 but the launch was delayed to 6 May 2014, then to 17 June 2014, then to 1 July 2014, again to 10 July 2014, again to 11 July 2014 due to test stand failure of an AJ-26 engine, to 12 July 2014 due to

weather Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere, the ...

, and finally to 13 July 2014, again due to weather. Orb-2 launched on 13 July 2014 at 16:52:14 UTC with berthing to the ISS following 3 days later on 16 July 2014. The Cygnus Orb-2 delivered of cargo to ISS and disposed of about of trash through destructive reentry.

Mission highlights

* Flight Day 1 (launch): after a 10-minute flight sequence, Antares launched Cygnus into orbit on the same plane as the

, but significantly below it. Cygnus then deployed its solar arrays after separation from Antares. After a series of checks, ground controllers commanded Cygnus to begin increasing its altitude. * Flight Days 2 and 3: Cygnus continued to increase its altitude to match that of the space station. * Flight Day 4: NASA made a go/no-go decision for Cygnus to berth with the station whereupon Cygnus first autonomously approached within below the space station, where it stopped and held position. Astronauts aboard the station then commanded Cygnus to a "free drift" mode, where they captured it with the station's robotic arm attached to the station's nadir node. * Flight Day 5 to Day 36: ISS Astronauts opened Cygnus' hatch, unloaded the payload and filled it with cargo for disposal. * Flight Day 36 through Day 41 Cygnus was detached from the station and maneuvered a safe distance away. Engineering tests were conducted for 2 days before a series of engine burns were conducted to slow the spacecraft for reentry over the South Pacific Ocean, where it and the cargo inside were destroyed.

Manifest

Total weight of cargo: * Crew supplies: ** Crew care packages ** Crew provisions ** Food * Hardware: ** Crew health care system hardware ** Environment control and life-support equipment ** Electrical power system hardware ** Extravehicular robotics equipment ** Flight crew equipment ** PL facility ** Structural and mechanical equipment ** Internal thermal control system hardware * Science and research: ** CubeSats and deployers ** Japan Aerospace Exploration Agency dynamic surf hardware ** Human research program resupply * Computer supplies: ** Command and data handling ** Photo and TV equipment * Spacewalk tools:

Images

File:Antares Orb-2 rollout (201407100001HQ).jpg, Night rollout from the Horizontal Integration Facility (HIF). File:Antares Orb-2 at Wallops pad (201407100027HQ).jpg, Raising of the rocket into launch position. File:Antares Orb-2 launch from Wallops (201407130015HQ).jpg, The Antares launch vehicle clears the TEL at liftoff. File:Orbital Sciences CRS Flight 2 liftoff from Arbuckle Neck.JPG, The launch as seen from a viewing site.

References