3MP No. 51P

Re-entered 10 Aug 1973

3MP No. 51P (NORAD 6776, COSPAR 1973-053A) was a SU satellite that re-entered Earth's atmosphere on 10 Aug 1973, launched on 9 Aug 1973 on the 3MP No. 51P mission. It was operated by IKI / BABTS as part of the 3M programme. The spacecraft was built by NPOL on the Mars bus, with a mass of 2,050 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.

1973

launched

1973

re-entered

years on orbit

2,050

kg mass

Lifecycle

Launched9 Aug 1973 · on the 3MP No. 51P mission

Operational9 Mar 1974 · entered service

Retired9 Mar 1974 · end of operational service

Re-entered10 Aug 1973 · atmospheric re-entry — object destroyed

Specifications

NORAD ID6776

COSPAR1973-053A

TypeSatellite

OperatorIKI / BABTS

Country / StateSU

ManufacturerNPOL

BusMars

Mass2,050 kg (1,900 kg dry)

Programme3M

CategoryPLAN

OrbitHEO (EEO)

Inclination51.5°

Frequently asked questions

What happened to 3MP No. 51P?

3MP No. 51P re-entered Earth's atmosphere on 10 Aug 1973, ending a mission that began with its launch in 1973. Objects in low orbits are gradually slowed by atmospheric drag until they fall back and burn up on re-entry.

When did 3MP No. 51P re-enter the atmosphere?

3MP No. 51P re-entered on 10 Aug 1973, according to Orbital Radar's historical catalogue records.

Who operated and built 3MP No. 51P?

3MP No. 51P was operated by IKI / BABTS and built by NPOL (SU).

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

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