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🛰️ SATELLITE · HISTORICAL RECORD

Kobal't No. 521

Re-entered 4 Jul 1991

Kobal't No. 521 (NORAD 21315, COSPAR 1991-036A) was a SU satellite that re-entered Earth's atmosphere on 4 Jul 1991, launched on 24 May 1991 on the Kobal't mission. It was operated by UNKSR as part of the Kobal't programme. The spacecraft was built by TSSKB on the Yantar'-4K2 bus, with a mass of 2,886 kg. Like most satellites in low orbits, it was gradually slowed by atmospheric drag until re-entry. Historical record from Orbital Radar's satellite archive, cross-referenced with the live satellite catalogue.

1991
launched
1991
re-entered
0
years on orbit
2,886
kg mass

Lifecycle

Launched24 May 1991 · on the Kobal't mission
Operational4 Jul 1991 · entered service
Retired4 Jul 1991 · end of operational service
Re-entered4 Jul 1991 · atmospheric re-entry — object destroyed

Specifications

NORAD ID21315
COSPAR1991-036A
TypeSatellite
OperatorUNKSR
Country / StateSU
ManufacturerTSSKB
BusYantar'-4K2
Mass2,886 kg
ProgrammeKobal't
CategoryIMG
OrbitLEO (LLEO/I)
Altitude185 × 364 km
Inclination67.1°

Frequently asked questions

What happened to Kobal't No. 521?

Kobal't No. 521 re-entered Earth's atmosphere on 4 Jul 1991, ending a mission that began with its launch in 1991. Objects in low orbits are gradually slowed by atmospheric drag until they fall back and burn up on re-entry.

When did Kobal't No. 521 re-enter the atmosphere?

Kobal't No. 521 re-entered on 4 Jul 1991, according to Orbital Radar's historical catalogue records.

Who operated and built Kobal't No. 521?

Kobal't No. 521 was operated by UNKSR and built by TSSKB (SU).

Historical record from the Orbital Radar satellite archive. Sources & methodology: data sources. Accessed 2026-09-06.