Service Module in shop
Credit: NASA. 60,788 bytes. 540 x 349 pixels.
The Alpha service module of the International Space Station had its origins a quarter century before it was launched. The Mir-2 space station was originally authorised in the February 1976 resolution setting forth plans for development of third generation Soviet space systems. It would undergo many changes over the year, with only one thing remaining constant: the starting point was always the DOS-8 base block space station core module, built as a back-up to the DOS-7 base block used in the Mir station.
DOS-8 serial number 128 was originally designed to have a three year service life in space. This was later increased to five years. The spaceframe was completed in February 1985 and major internal equipment was installed by October 1986. Until Reagan's 1983 announcement of the Star Wars programme, Mir-2 was to be a relatively modest station, a near-duplicate of Mir assembled after the end of its planned five year life.
The decision by Soviet Premier Andropov to compete with America in military dominance from space lead to a huge expansion of Soviet space station plans. As design continued the station grew to immense proportions. The draft project for this greatly expanded station was approved by NPO Energia Chief Semenov on 14 December 1987 and announced to the press as 'Mir-2' in January 1988. The station would be built in a 65 degree orbit and consist mainly of enormous 90 tonne modules. But the first launch, as always, was the DOS 8. Assembly of the station was expected to begin in 1993.
As the Soviet Union disintegrated plans for this station were scaled down. By 1991 the Energia modules were out of the picture and the drastically reduced 'Mir 1.5', was under consideration. DOS-8 would be equipped by Buran with 37KBE power modules and two operational 37KBT biotechnology modules. By 1992 Buran was now out of the picture and the plan was reduced in scale again. These revised plans were approved by the Council of Chief Designers on 24 November 1992. Mir-2 would now consist of the DOS-8 core module, and a cross beam called the NEP (scientific-energy platform). The add-on modules were reduced in size for launch by either the Soyuz or Zenit launch vehicles.
By November 1992 further financial difficulties and uncertainties with America's Freedom space station led Russia and the European Space Agency to open discussions on joint development and use of Mir-2. This circle was expanded in the summer of 1993 when Energia briefed NASA on the Mir-2. Finally in November 1983 Freedom, Mir-2, and the European and Japanese modules were incorporated into a single International Space Station. Among these is the Alpha Service Module - the DOS-8 station, finally to be launched as the second major ISS module during 2000. Maximum Diameter: 4.2 m. Electrical System: Solar cells.