Columbus is a science laboratory that is part of the International Space Station (ISS) and is the largest single contribution to the ISS made by the European Space Agency (ESA).
Like the Harmony and Tranquility modules, the Columbus laboratory was constructed in Turin, Italy by Rome based Alcatel Alenia Space with respect to structures and thermal control. The functional architecture (including software) of the lab was designed by EADS in Germany where it was also integrated before being flown to the Kennedy Space Center (KSC) in Florida in an Airbus Beluga. It was launched aboard Space Shuttle Atlantis on February 7, 2008 on flight STS-122. It is designed for ten years of operation. The module is controlled by the Columbus Control Centre, located at the German Space Operations Centre, part of the German Aerospace Center in Oberpfaffenhofen near Munich, Germany.
The European Space Agency has spent €1.4 billion (about US$2 billion) on building Columbus, including the experiments that will fly in it and the ground control infrastructure necessary to operate them.[1]
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The laboratory is a cylindrical module with two end cones. It is 4,477 mm (15 ft) in external diameter and 6,871 mm (23 ft) in overall length, excluding the projecting external experiment racks. Its shape is very similar to that of the Multi-Purpose Logistics Modules (MPLMs), since both were designed to fit in the cargo bay of a Space Shuttle orbiter. The starboard end cone contains most of the laboratory's on-board computers. The port end cone contains the Common Berthing Mechanism.
ESA chose EADS Astrium Space Transportation as prime contractor for Columbus. The Columbus flight structure, the micro-meteorite protection system, the active and passive thermal control, the environmental control, the harness and all the related ground support equipment were designed and qualified by Alcatel Alenia Space in Turin, Italy as defined by the PICA - Principle (for definition see History below); the related hardware was pre-integrated and sent as PICA in September 2001 to Bremen. The lab was then fully integrated and qualified on system level at the EADS Astrium Space Transportation facilities in Bremen, Germany.
In November 2007, Columbus was moved out of the KSC Space Station Processing Facility, and installed into the payload bay of the Atlantis orbiter for launch on ISS assembly flight 1E.[2][3] During cryo-filling of the space shuttle External Tank (ET) with liquid hydrogen and liquid oxygen prior to the first launch attempt on December 6, 2007, two of four LH2 ECO sensors failed a test. Mission rules called for at least three of the four sensors to be in working order for a launch attempt to proceed. As a result of the failure, the Launch Director Doug Lyons postponed the launch, initially for 24 hours. This was later revised into a 72 hour delay, resulting in a next launch attempt set for Sunday December 9, 2007. This launch attempt was scrubbed when one of the ECO sensors again failed during fuelling.
The ECO sensors external connector was changed on the space shuttle external tank, causing a two month delay in the launch. Columbus was finally launched successfully on the third attempt at 2:45pm EST, February 7, 2008.[4] Once at the station, Canadarm2 removed Columbus from the docked shuttle's cargo bay and attached it to the starboard hatch of Harmony (also known as Node 2), with the cylinder pointing outwards on February 11, 2008.[5]
Activities in the lab are controlled on the ground by the Columbus Control Centre (at DLR Oberpfaffenhofen in Germany) and by the associated User Support Operations Centres throughout Europe.
The laboratory can accommodate ten active International Standard Payload Racks (ISPRs) for science payloads. Agreements with NASA allocate to ESA 51% usage of the Columbus Laboratory.[6] ESA is thus allocated five active rack locations, with the other five being allocated to NASA. Four active rack locations are on the forward side of the deck, four on the aft side, and two are in overhead locations. Three of the deck racks are filled with life support and cooling systems. The remaining deck rack and the two remaining overhead racks are storage racks.
In addition, four un-pressurized payload platforms can be attached outside the starboard cone, on the Columbus External Payload Facility (CEPF).[7] Each external payload is mounted on an adaptor able to accommodate small instruments and experiments totalling up to 230 kilograms (507 lb).[8]
The following European ISPRs have been initially installed inside Columbus:
The first external payloads were mounted on Columbus by crew members of the mission STS-122 mission. The three payloads mounted are:
Planned additional external payload:
See also:
Columbus was originally planned as part of the Columbus program, an ESA program to develop an autonomous manned space station that could be used for a variety of microgravity experiments. The program ran from 1986 to 1991 and included three components: a Man-Tended Free Flyer (MTFF) element serviced by the Hermes shuttle, an Attached Pressurized Module (APM), and a Polar Platform (PPF). After several budget cuts and cancellation of Hermes shuttle, all that remained in the Columbus program was the APM, finally renamed to Columbus.
When only the APM was left in the program there were not enough tasks for the two main contributors Germany and Italy represented by MBB-ERNO and Alenia respectively. As compromise the PICA (Pre Integrated Columbus APM) - Principle was invented meaning a split responsibility where Alenia as a co-prime is responsible for the overall Columbus configuration, the mechanical and thermal/life support systems, HFE and harness design/manufacturing whereas EADS Astrium Space Transportation is responsible for the overall Columbus design and all Avionics systems including electrical harness design and software.[10] Splitting off systems engineering responsibility and harness design under separate fixed-price contracts was found not to be advantageous with respect to efficiency and fast decision making as financial reasonings were pre-dominant in the last phase of development and verification.
The structure used for Columbus is based on the MPLM module built for NASA by Thales Alenia Space. In 2000 the pre-integrated module (structure including harness and tubing) was delivered to Bremen in Germany by the Co-prime contractor Alenia. The final integration and system testing was performed by the overall prime contractor EADS Astrium Space Transportation, after that the initial Payload was integrated and the overall complement checked-out.
On May 27, 2006 Columbus was flown from Bremen, Germany to Kennedy Space Center on board an Airbus Beluga.
The final schedule was much longer than originally planned due to development problems (several caused by the complex responsibility splitting between the Co-prime and the Overall prime contractor) and design changes introduced by ESA but being affordable due to the Shuttle problems delaying the Columbus launch for several years. The main design change was the addition of the External Payload Facility (EPF), which was driven by the different European Payload organizations being more interested in outer space than internal experiments. Also the addition of a terminal for direct communications to/from ground, which could have been used also as back-up for the ISS system, was studied but not implemented for cost reasons.
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