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Long Duration Exposure Facility

LDEF, shortly before deployment, flies on the RMS arm of Space Shuttle Challenger over Baja California.

Mission type
Materials research

Operator
NASA

COSPAR ID
1984-034B

SATCAT №
14898

Website
setas-www.larc.nasa.gov/LDEF/

Mission duration
2076 days

Distance travelled
1,374,052,506 km (853,796,644 mi)

Orbits completed
32,422

Spacecraft properties

Manufacturer
Langley

Launch mass
9,700 kg (21,400 lb)

Start of mission

Launch date
April 6, 1984, 13:58:00 (1984-04-06UTC13:58Z) UTC

Rocket
Space Shuttle Challenger
STS-41-C

Launch site
Kennedy LC-39A

End of mission

Recovered by
Space Shuttle Columbia
STS-32

Recovery date
January 12, 1990, 15:16 (1990-01-12UTC15:17Z) UTC

Landing date
January 20, 1990, 09:35:37 UTC

Landing site
Edwards Runway 22

Orbital parameters

Reference system
Geocentric

Regime
Low Earth

Eccentricity
7.29E-4

Perigee
473.0 km (293.9 mi)

Apogee
483.0 km (300.1 mi)

Inclination
28.5 degrees

Period
94.2 minutes

NASA’s Long Duration Exposure Facility, or LDEF (acronym pronounced “EL-deaf”), was a school bus-sized cylindrical facility designed to provide long-term experimental data on the outer space environment and its effects on space systems, materials, operations and selected spore’s survival.[1][2] It was placed in low Earth orbit by Space Shuttle Challenger in April 1984. The original plan called for the LDEF to be retrieved in March 1985, but after a series of delays it was eventually returned to Earth by Columbia in January 1990.[2]
It successfully carried science and technology experiments for about 5.7 years, that have revealed a broad and detailed collection of space environmental data. LDEF’s 69 months in space provided scientific data on the long-term effects of space exposure on materials, components and systems that has benefited NASA spacecraft designers to this day.[3]

Contents

1 History
2 Launch
3 Experiments

3.1 EXOSTACK

4 Retrieval
5 See also
6 References
7 External links

History[edit]
Researchers identified the