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🛰️ SATELLITE · HISTORICAL RECORD

Bion No. 4L

Re-entered 22 Aug 1977

Bion No. 4L (NORAD 10172, COSPAR 1977-074A) was a SU satellite that re-entered Earth's atmosphere on 22 Aug 1977, launched on 3 Aug 1977 on the Bion No. 4 mission. It was operated by IMBP / TSSKB as part of the Bion programme. The spacecraft was built by TSSKB on the Bion bus, with a mass of 2,040 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.

1977
launched
1977
re-entered
0
years on orbit
2,040
kg mass

Lifecycle

Launched3 Aug 1977 · on the Bion No. 4 mission
Operational22 Aug 1977 · entered service
Retired22 Aug 1977 · end of operational service
Re-entered22 Aug 1977 · atmospheric re-entry — object destroyed

Specifications

NORAD ID10172
COSPAR1977-074A
TypeSatellite
OperatorIMBP / TSSKB
Country / StateSU
ManufacturerTSSKB
BusBion
Mass2,040 kg
ProgrammeBion
CategoryBIO
OrbitLEO (LLEO/I)
Altitude215 × 392 km
Inclination62.8°

Frequently asked questions

What happened to Bion No. 4L?

Bion No. 4L re-entered Earth's atmosphere on 22 Aug 1977, ending a mission that began with its launch in 1977. Objects in low orbits are gradually slowed by atmospheric drag until they fall back and burn up on re-entry.

When did Bion No. 4L re-enter the atmosphere?

Bion No. 4L re-entered on 22 Aug 1977, according to Orbital Radar's historical catalogue records.

Who operated and built Bion No. 4L?

Bion No. 4L was operated by IMBP / TSSKB and built by TSSKB (SU).

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