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// missile early warning · 1991

IBSS-SPAS

Free-flying experiment carried on Space Shuttle mission STS-39. IBSS-SPAS was launched on April 28, 1991 aboard a Space Shuttle from Cape Canaveral & Kennedy. Latest status in GCAT: attached to another object (May 1, 1991).

COSPAR 1991-031BNORAD 21244United States

Identity

Name in GCAT
IBSS/SPAS
Common name
IBSS-SPAS
Payload designation
SPAS-2
International designator
1991-031B
NORAD catalog number
21244
GCAT identifier
S21244
UN registration
ST/SG/SER.E/258

Mission

Mission type
Missile early warning, Technology
Use
Defense
Program
SPAS
Owner
SDIO
Country
United States
Builder
Deutsche Aerospace AG (DASA)-Ottobrunn
Platform (bus)
SPAS

Launch

Date
April 28, 1991 · 11:33 UTC
Launch record
1991-031Success
Spaceport
Cape Canaveral & Kennedy · pad LC39A

Orbit and fate

Orbit class (GCAT)
LLEO/I
Perigee
242 km
Apogee
257 km
Inclination
56.99°
Status
Attached to another object
Status date
May 1, 1991
Last known active
May 4, 1991
End of operations
May 4, 1991

Size

Mass
1,835 kg
Dry mass
1,793 kg
Length
4.8 m
Diameter
1.50 m
Span
4.8 m

Source: GCAT payload, deep-space and lander catalogs, Jonathan C. McDowell (CC BY 4.0); Wikidata Q5915906 (CC0).