Cygnus spacecraft
Encyclopedia
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| Description | ||
| Role: | Under development To be used to supply the International Space Station because of the retirement of the Space Shuttle |
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| Crew: | 0 | |
| Carrier Rocket: | Taurus II Taurus II Taurus II is an expendable launch system being developed by Orbital Sciences Corporation. It is a two stage vehicle designed to launch payloads weighing up to into low-Earth orbit... |
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| Dimensions | ||
| Height: | 3.66 m /4.86 m | 12.0 ft / 15.88 ft |
| Diameter: | 3.07 m /3.07 m | 10.07 ft / 10.07 ft |
| Weight (dry): | 1,500 kg/ 1,800 kg | |
| Volume: | 18.9 m3/ 26.2 m3 | |
| Delivered Payload: | 2,000 kg/ 2,700 kg | 4,400 lb/ 5,950 lb |
| Disposal Payload: | 1,200 kg | 2,600 lb |
| Performance | ||
| Endurance: | Yet to be specified | |
The Cygnus spacecraft is an unmanned resupply spacecraft
Unmanned resupply spacecraft
Unmanned resupply spacecraft are a special kind of robotic spacecraft that operate autonomously without a human crew, designed to support space station operation...
being developed by Orbital Sciences Corporation
Orbital Sciences Corporation
Orbital Sciences Corporation is an American company which specializes in the manufacturing and launch of satellites. Its Launch Systems Group is heavily involved with missile defense launch systems...
and Thales Alenia Space
Thales Alenia Space
Thales Alenia Space is an aerospace company born after the Thales Group bought the participation of Alcatel in the two joint-ventures between Alcatel and Finmeccanica, Alcatel Alenia Space and Telespazio.-History:...
as part of NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
's COTS
Commercial Orbital Transportation Services
Commercial Orbital Transportation Services is a NASA program to coordinate the delivery of crew and cargo to the International Space Station by private companies. The program was announced on January 18, 2006...
project. It is designed to transport supplies to the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...
(ISS) after the retirement of the Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...
. Since August 2000 unmanned ISS resupply missions have been regularly flown by Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
n Progress spacecraft
Progress spacecraft
The Progress is a Russian expendable freighter spacecraft. The spacecraft is an unmanned resupply spacecraft during its flight but upon docking with a space station, it allows astronauts inside, hence it is classified manned by the manufacturer. It was derived from the Soyuz spacecraft, and is...
, as well as by two flights of the European Automated Transfer Vehicle
Automated Transfer Vehicle
The Automated Transfer Vehicle or ATV is an expendable, unmanned resupply spacecraft developed by the European Space Agency . ATVs are designed to supply the International Space Station with propellant, water, air, payload and experiments...
and two flights of the Japanese H-II Transfer Vehicle
H-II Transfer Vehicle
The H-II Transfer Vehicle , called , is an unmanned resupply spacecraft used to resupply the Kibō Japanese Experiment Module and the International Space Station . The Japan Aerospace Exploration Agency has been working on the design since the early 1990s. The first mission, HTV-1, was originally...
. With the Cygnus spacecraft, NASA seeks to increase its partnerships with domestic commercial aviation and aeronautics industry.
Development
With Rocketplane KistlerRocketplane Kistler
Rocketplane Kistler was a reusable spacecraft firm originally based in Oklahoma before moving to Wisconsin. Formed in 2006 by Rocketplane Limited, Inc...
unable to meet funding obligations for its K-1 launch vehicle under the terms of the COTS agreement, NASA decided on October 18, 2007 to terminate its contract with Rocketplane Kistler and re-award its contract after a competition. On February 19, 2008 NASA announced that it had chosen Orbital Sciences as the new winner. On December 23, 2008, NASA awarded Orbital Sciences a $1.9 billion contract under the Commercial Resupply Services plan. Under this contract, Orbital Sciences will deliver up to 20 tons of cargo to the ISS through 2016 in eight Cygnus spacecraft flights.
By April 2010 Orbital had displayed a full-scale model of the Cygnus cargo delivery spacecraft at the National Space Symposium (NSS) in Colorado Springs, CO.
The first Cygnus demonstration flight was originally expected in late 2010, launched by a Taurus II
Taurus II
Taurus II is an expendable launch system being developed by Orbital Sciences Corporation. It is a two stage vehicle designed to launch payloads weighing up to into low-Earth orbit...
rocket. This has now been postponed to December 2011.
Design
The Cygnus spacecraft consists of two basic components: the service module and the cargo module. The service module is based on Orbital's STARSTAR Bus
STAR Bus is a satellite platform manufactured by Orbital Sciences Corporation with an apogee kick motor to place a communications satellite into geostationary orbit, a thruster to provide the satellite with orbital station-keeping for a 15 year mission, and solar arrays to provide the satellite...
spacecraft bus as well as components from the development of the Dawn spacecraft. It is currently expected to have a gross mass of 1,800 kg with propulsion provided by thrusters using the hypergolic propellants hydrazine
Hydrazine
Hydrazine is an inorganic compound with the formula N2H4. It is a colourless flammable liquid with an ammonia-like odor. Hydrazine is highly toxic and dangerously unstable unless handled in solution. Approximately 260,000 tons are manufactured annually...
and nitrogen tetroxide
Dinitrogen tetroxide
Dinitrogen tetroxide is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide; some call this mixture dinitrogen tetroxide, while some call it nitrogen dioxide.Dinitrogen tetroxide is a powerful oxidizer, making it highly...
and is capable of producing up to 4 kW of electrical power via two gallium arsenide solar arrrays. On November 12, 2009, Dutch Space announced it will provide solar arrays for nine Cygnus spacecraft under a contract valued at more than $35 million.
There are two types of cargo modules slated for use with the spacecraft. The first type is a pressurized cargo module based on the Italian-built Multi-Purpose Logistics Module
Multi-Purpose Logistics Module
A Multi-Purpose Logistics Module is a large pressurized container used on Space Shuttle missions to transfer cargo to and from the International Space Station . An MPLM was carried in the cargo bay of a Shuttle and berthed to the Unity or Harmony modules on the ISS. From there, supplies were...
. This version is expected to have a gross mass of 3,500 kg, a payload mass of 2,000 kg and a total pressurized volume of 18.7 m³. The second type is based on a variant of NASA's ExPRESS Logistics Carrier
EXPRESS Logistics Carrier
An ExPRESS logistics carrier is an unpressurized attached payload platform for the International Space Station that provides mechanical mounting surfaces, electrical power, and command and data handling services for Orbital Replacement Units as well as science experiments on the ISS...
. This variant will also have a gross mass of 3,500 kg with an expected payload mass of 2,000 kg, depending on the configuration being used, and an expected total cargo volume of 18.1 m³. The spacecraft will dock with the International Space Station by maneuvering close to the space station where the Canadarm2 robotic arm will grapple the spacecraft and attach it to a Common Berthing Mechanism
Common Berthing Mechanism
The common berthing mechanism is a berthing mechanism used to connect all non-Russian pressurized modules of the International Space Station....
on the Harmony module in a similar fashion to the Japanese H-II Transfer Vehicle
H-II Transfer Vehicle
The H-II Transfer Vehicle , called , is an unmanned resupply spacecraft used to resupply the Kibō Japanese Experiment Module and the International Space Station . The Japan Aerospace Exploration Agency has been working on the design since the early 1990s. The first mission, HTV-1, was originally...
. Neither cargo module provides return capability but modules can be loaded with obsolete equipment and trash for destructive reentry similar to Russian Progress modules.
A Cygnus variant with a robotic arm is being considered. Such a variant would be a space tug suitable for supporting the International Space Station, other space stations and propellant depots.
See also
- Unmanned resupply spacecraftUnmanned resupply spacecraftUnmanned resupply spacecraft are a special kind of robotic spacecraft that operate autonomously without a human crew, designed to support space station operation...
- descriptions of other similar vehicles:- Automated Transfer VehicleAutomated Transfer VehicleThe Automated Transfer Vehicle or ATV is an expendable, unmanned resupply spacecraft developed by the European Space Agency . ATVs are designed to supply the International Space Station with propellant, water, air, payload and experiments...
- a similar cargo vehicle developed by European Space AgencyEuropean Space AgencyThe European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
, it is currently in use re-supplying the International space stationInternational Space StationThe International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...
(ISS). Flight and docking is automatic. - Dragon Cargo spacecraft - a similar cargo vehicle in development, also capable of returning 3000 kg of cargo to Earth, developed by Space Exploration TechnologiesSpaceXSpace Exploration Technologies Corporation, or more popularly and informally known as SpaceX, is an American space transport company that operates out of Hawthorne, California...
- H-II Transfer VehicleH-II Transfer VehicleThe H-II Transfer Vehicle , called , is an unmanned resupply spacecraft used to resupply the Kibō Japanese Experiment Module and the International Space Station . The Japan Aerospace Exploration Agency has been working on the design since the early 1990s. The first mission, HTV-1, was originally...
- a similar cargo vehicle developed by Japan Aerospace Exploration AgencyJapan Aerospace Exploration AgencyThe , or JAXA, is Japan's national aerospace agency. Through the merger of three previously independent organizations, JAXA was formed on October 1, 2003, as an Independent Administrative Institution administered by the Ministry of Education, Culture, Sports, Science and Technology and the...
, it is currently in use. Flight is automatic, it is manually captured by an ISS robotic arm and berthed to the station. - Progress spacecraft - a similar cargo vehicle developed by Russian Federal Space AgencyRussian Federal Space AgencyThe Russian Federal Space Agency , commonly called Roscosmos and abbreviated as FKA and RKA , is the government agency responsible for the Russian space science program and general aerospace research. It was previously the Russian Aviation and Space Agency .Headquarters of Roscosmos are located...
it is currently in use. As of March 2011 it has completed 41 resupply missions to the ISS. Progress flight and docking is fully automatic, with mission control and ISS crew having a normally supervisory role only.
- Automated Transfer Vehicle