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Cygnus OA-7

NSSDCA/COSPAR ID: 2017-019A

Description

Orbital ATK’s Cygnus spacecraft, alongside SpaceX’s Dragon, is one of two spacecraft NASA use to deliver cargo to the International Space Station as part of the Commercial Resupply Services (CRS) program. Cygnus first flew in 2013, conducting a demonstration mission under NASA’s Commercial Orbital Transportation Services (COTS) program. The Cygnus spacecraft consists of a pressurized cargo module (PCM) and a service module built with Orbital’s experience of developing free-flying spacecraft with its GEOStar and LEOStar satellite busses. The cargo module was constructed by Thales Alenia Space and is derived from the Multi-Purpose Logistics Modules (MPLMs) that were carried to the station during the Space Shuttle program. An enhanced version of the Cygnus, with an extended cargo module and redesigned solar arrays and fuel tanks, debuted in December 2015 and is now the standard for all missions.

Cygnus was a late addition to the Commercial Orbital Transport Services program, taking the place of Rocketplane Kistler’s K-1 vehicle, whose funding was canceled in 2007 after the company had been unable to meet project milestones. Orbital was awarded the contract to develop Cygnus in February 2008 as part of a second round of bidding. In December 2008 Orbital was awarded a Commercial Resupply Services contract for eight resupply missions. This was reduced by one following enhancements to the Cygnus spacecraft and the use of the more powerful Atlas rockets for the OA-4 and OA-6 launches, which reduced the number of missions that would be needed to deliver the required amount of payload. NASA has since extended the original CRS contract to eleven missions and awarded Orbital a new contract under the second phase of the CRS program for a minimum of six additional flights. However, Tuesday’s mission – OA-7 – will be the last of those in the original award to fly.

The OA-7 spacecraft is named the SS John Glenn, after the astronaut who was the first American to orbit the Earth. Glenn, a member of NASA’s original Mercury Seven astronaut group, was born in July 1921 and became the third American to fly in space aboard his Friendship 7 spacecraft during February 1962’s Mercury-Atlas 6 mission. Launching atop an Atlas LV-3B rocket – a modified Atlas D missile – Glenn’s capsule completed three orbits of the Earth before being deorbited for landing in the Atlantic Ocean, almost five hours after liftoff. Glenn was the fifth man to fly in space – following Soviet cosmonauts Yuri Gagarin and Gherman Titov, who completed orbital missions aboard Vostok spacecraft, and American astronauts Alan Shepard and Virgil ‘Gus’ Grissom, who made suborbital flights aboard Mercury spacecraft boosted by smaller Redstone rockets. Before his selection as an astronaut, Glenn served in the US Marine Corps as a naval aviator, seeing action in the Pacific during the Second World War and in the Korean War before becoming a test pilot.

As the first American to complete an orbital space mission, Glenn became a national hero. This status resulted in him being removed from active flight status and he subsequently resigned from NASA to enter politics. As a member of the Democratic Party, Glenn was elected to Congress in 1974 as a Senator for the state of Ohio, serving until 1999. Glenn made a bid for the Presidency in the 1984 election, losing the Democratic nomination to Walter Mondale. John Glenn returned to space in 1998, at the age of 77, flying as a payload specialist aboard Space Shuttle Discovery during the STS-95 mission. In the process, Glenn became the oldest person to fly in space, a record which still stands. He was the last member of the Mercury Seven to fly a space mission, and the only Mercury astronaut to fly aboard the Shuttle. The last surviving member of the Mercury Seven, Glenn died on 8 December last year. He was laid to rest at Arlington National Cemetery with full military honors earlier this month.

Alternate Names

    Facts in Brief

    Launch Date: 2017-04-18
    Launch Vehicle: Atlas V
    Launch Site: Cape Canaveral, United States

    Funding Agency

    • National Aeronautics and Space Administration (United States)

    Discipline

    • Resupply/Refurbishment/Repair

    Additional Information

    Questions and comments about this spacecraft can be directed to: Coordinated Request and User Support Office

     
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