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🛰️ SATELLITE · HISTORICAL RECORD

TDA 4

Re-entered 11 Jul 1966

TDA 4 (NORAD 2186, COSPAR 1966-046A) was a US satellite that re-entered Earth's atmosphere on 11 Jul 1966, launched on 1 Jun 1966 on the TDA 4 mission. It was operated by MSC as part of the TDA programme. The spacecraft was built by MCDA on the TDA bus, with a mass of 910 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.

1966
launched
1966
re-entered
0
years on orbit
910
kg mass

Lifecycle

Launched1 Jun 1966 · on the TDA 4 mission
Operational14 Jun 1966 · entered service
Retired14 Jun 1966 · end of operational service
Re-entered11 Jul 1966 · atmospheric re-entry — object destroyed

Specifications

NORAD ID2186
COSPAR1966-046A
TypeSatellite
OperatorMSC
Country / StateUS
ManufacturerMCDA
BusTDA
Mass910 kg
ProgrammeTDA
CategorySS
OrbitLEO (LLEO/I)
Altitude286 × 288 km
Inclination28.9°

Frequently asked questions

What happened to TDA 4?

TDA 4 re-entered Earth's atmosphere on 11 Jul 1966, ending a mission that began with its launch in 1966. Objects in low orbits are gradually slowed by atmospheric drag until they fall back and burn up on re-entry.

When did TDA 4 re-enter the atmosphere?

TDA 4 re-entered on 11 Jul 1966, according to Orbital Radar's historical catalogue records.

Who operated and built TDA 4?

TDA 4 was operated by MSC and built by MCDA (US).

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