Object D Satellite Bus
Data current as of 2026-07-20.
The Object D bus accounts for 5 cataloged objects, of which 2 are in orbit and 0 are active. 3 have reentered. Most are built by OKB1. The largest operator on this bus is OKB1. The first launched in 1958, the most recent in 1964.
2
In orbit
0
Active
5
Total launched
3
Reentered
Object D launched per year
Still in orbit Since reentered Click a year to list its satellites.
Typical specifications
Most common values across cataloged Object D satellites.
| Manufacturer | OKB1 |
|---|---|
| Purpose | Magnetospheric research |
| Launch mass | 350 kg |
| Dry mass | 350 kg |
| Length | 1.5 m |
| Diameter | 0.65 m |
| Span | 4 m |
| Shape | Domed Cyl+Ant+pan |
| Power | 6 deployable solar arrays, batteries |
| Propulsion | SRM |
| Typical orbit | 156 min period, 61° inclination |
Top operators
OKB1 5
Top countries
SU 5
Object D satellites
Track any of them live in KeepTrack.
| Name | NORAD | COSPAR | Owner | Launched | Orbit | Status | Track |
|---|---|---|---|---|---|---|---|
| ELEKTRON 4 Elektron-4 | 00830 | 1964-038B | OKB1 | Jul 10, 1964 | 1271 min, 65.9° | Reentered | ◉ |
| ELEKTRON 3 Elektron-3 | 00829 | 1964-038A | OKB1 | Jul 10, 1964 | 156 min, 60.8° | Inactive | ◉ |
| ELEKTRON 2 Elektron-2 | 00748 | 1964-006B | OKB1 | Jan 30, 1964 | 120 min, 56.7° | Reentered | ◉ |
| ELEKTRON 1 Elektron-1 | 00746 | 1964-006A | OKB1 | Jan 30, 1964 | 158 min, 60.9° | Inactive | ◉ |
| SPUTNIK 3 3-y Sovetskiy ISZ | 00008 | 1958-004B | OKB1 | May 15, 1958 | 88 min, 65.1° | Reentered | ◉ |
Frequently asked questions
How many Object D satellites are there?
The catalog lists 5 objects built on the Object D bus. 2 are in orbit and 3 have reentered.
How many Object D satellites are in orbit?
2 Object D objects are currently in orbit, of which 0 carry an active status.
Who builds the Object D bus?
The Object D bus is most commonly built by OKB1.
When did the first Object D satellite launch?
The first cataloged Object D satellite launched in 1958, and the most recent in 1964.