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Habitable module LM1, Image courtesy T. Richter - click to enlarge

Spacelab was a manned scientific module for the US Space Shuttle. A Memorandum of Understanding signed 24 September 1973 between NASA and the ESA gave Europe the responsibility to fund, design, and build Spacelab.

The Spacelab system has several components: The habitable pressure module, the pallet, the Igloo, the Instrument Point System, and a connecting tunnel.

Pressure Module

spacelab diagram
Credit: NASA

The Pressure Module was configurable as either a Long Module (LM) or a Short Module (SM). The short configuration was never used. The long version consisted of two 4.1 m diameter aluminum cylinders with conical end pieces. Experiment racks were integrated on the module floor outside the module itself, then slid into one end along support beams. Space above the ceiling and beneath the floor were used for storage. There were two 1.3 m apertures located on the top. The forward aperture contained a window and the aft aperture had an airlock for exposing experiments to space. Two of the pressure modules were built. LM1 is on display at the Steven F. Udvar-Hazy Center. LM2 is on display at the Bremenhalle exhibit atop Terminal 3 in the Bremen Airport, Bremen, Germany.


Credit: ESA

Pallets were U-shaped and were fully integrated before being inserted into the payload bay. These pallets proved to be so useful that they were often used on missions not related to Spacelab.


igloo and pallet
Foreground: Igloo, Background: Pallet (Credit: NASA)

On missions were the pressure module was not present, a pressurized Igloo accommodated experiment avionics. Two Igloos were manufactured. They were 2.4 m high with a diameter of 1.1 m.

Instrument Pointing System

Credit: NASA

The Instrument Pointing System (IPS) provided precision pointing and control of astronomical telescopes. The above photo is from the December 1990 ASTRO-1 mission.


On missions which included a pressure module, a tunnel was connected from one end of the pressure module directly to the shuttle cabin so astronauts could enter in shirt sleeves.

spacelab 1
Spacelab-1 in orbit, 1983 (Credit: NASA)

Spacelab Missions
Shuttle Flight Launch Date Mission Pressurized Module Unpressurized Modules
STS-9 28 November 1983 Spacelab-1 LM1 1 Pallet
51-B 29 April 1985 Spacelab-3 LM1 MPESS
51-F 29 July 1985 Spacelab-2 Igloo 3 Pallets, IPS
61-A 30 October 1985 Spacelab-D1 LM2 MPESS
STS-35 2 December 1990 ASTRO-1 Igloo 2 Pallets, IPS
STS-40 5 June 1991 SLS-1 LM1  
STS-42 22 January 1992 IML-1 LM2  
STS-45 24 March 1992 ATLAS-1 Igloo 2 Pallets
STS-50 25 June 1992 USML-1 LM1 EDO
STS-47 12 September 1992 Spacelab-J LM2  
STS-56 8 April 1993 ATLAS-2 Igloo 1 Pallet
STS-55 26 April 1993 Spacelab-D2 LM1 USS
STS-58 18 October 1993 SLS-2 LM2 EDO
STS-65 8 July 1994 IML-2 LM1 EDO
STS-66 3 November 1994 ATLAS-3 Igloo 1 Pallet
STS-67 2 March 1995 ASTRO-2 Igloo 2 Pallets, EDO
STS-71 27 June 1995 Spacelab-Mir LM2  
STS-73 20 October 1995 USML-2 LM1 EDO
STS-78 20 June 1996 LMS LM2 EDO
STS-83 4 April 1997 MSL-1 LM1 EDO
STS-94 1 July 1997 MSL-1R LM1 EDO
STS-90 17 April 1998 Neurolab LM2 EDO

ASTRO: Astronomical Observatory
ATLAS: Atmospheric Laboratory for Applications and Science
EDO: Extended Duration Orbiter
IML: International Microgravity Laboratory
IPS: Instrument Pointing System
LM: Long Module
LMS: Life and Microgravity Spacelab
MPESS: Mission Peculiar Experiment Support Structure
MSL: Microgravity Sciences Laboratory
SLS: Spacelab Life Sciences
USML: US Microgravity Laboratory


Page last modified: 11 February 2022 09:16:20.