DMSP Block 4A Satellite Bus
Data current as of 2026-07-20.
The DMSP Block 4A bus accounts for 4 cataloged objects, of which 4 are in orbit and 0 are active. Most are built by RCA. The largest operator on this bus is AFSSD. The first launched in 1966, the most recent in 1967.
4
In orbit
0
Active
4
Total launched
0
Reentered
DMSP Block 4A launched per year
Still in orbit Click a year to list its satellites.
Typical specifications
Most common values across cataloged DMSP Block 4A satellites.
| Manufacturer | RCA |
|---|---|
| Purpose | Meteorology |
| Launch mass | 79 kg |
| Dry mass | 79 kg |
| Length | 0.7 m |
| Diameter | 0.8 m |
| Span | 0.8 m |
| Shape | Oct Cyl |
| Power | Solar cells, batteries |
| Propulsion | ? |
| Equipment | ? |
| Typical orbit | 98 min period, 99° inclination |
Top operators
AFSSD 2 SAMSO 2
Top countries
US 4
DMSP Block 4A satellites
Track any of them live in KeepTrack.
| Name | NORAD | COSPAR | Owner | Launched | Orbit | Status | Track |
|---|---|---|---|---|---|---|---|
| OPS 1264 (DMSP 4A F4) OPS 1264 | 02980 | 1967-096A | SAMSO | Oct 11, 1967 | 98 min, 99.2° | Inactive | ◉ |
| OPS 7202 (DMSP 4A F3) OPS 7202 | 02920 | 1967-080A | SAMSO | Aug 23, 1967 | 102 min, 98.6° | Inactive | ◉ |
| OPS 6073 (DMSP 4A F2) OPS 6073 | 02669 | 1967-010A | AFSSD | Feb 8, 1967 | 101 min, 99.1° | Inactive | ◉ |
| OPS 6026 (DMSP 4A F1) OPS 6026 | 02418 | 1966-082A | AFSSD | Sep 16, 1966 | 100 min, 98.3° | Inactive | ◉ |
Frequently asked questions
How many DMSP Block 4A satellites are there?
The catalog lists 4 objects built on the DMSP Block 4A bus. 4 are in orbit and 0 have reentered.
How many DMSP Block 4A satellites are in orbit?
4 DMSP Block 4A objects are currently in orbit, of which 0 carry an active status.
Who builds the DMSP Block 4A bus?
The DMSP Block 4A bus is most commonly built by RCA.
When did the first DMSP Block 4A satellite launch?
The first cataloged DMSP Block 4A satellite launched in 1966, and the most recent in 1967.