HS-351 Satellite Bus
Data current as of 2026-07-20.
The HS-351 bus accounts for 4 cataloged objects, of which 4 are in orbit and 0 are active. Most are built by HSES. The largest operator on this bus is COM. The first launched in 1976, the most recent in 1981.
4
In orbit
0
Active
4
Total launched
0
Reentered
HS-351 launched per year
Still in orbit Click a year to list its satellites.
Typical specifications
Most common values across cataloged HS-351 satellites.
| Manufacturer | HSES |
|---|---|
| Purpose | Communication |
| Launch mass | 748 kg |
| Dry mass | 590 kg |
| Length | 3.5 m |
| Diameter | 2.4 m |
| Span | 6.3 m |
| Shape | Cyl + Ant |
| Power | Solar cells (body mounted), batteries |
| Propulsion | SVM-4A |
| Design life | 7 years |
| Equipment | 24 C-band transponders |
| Typical orbit | 1436 min period, 8° inclination |
Top operators
COM 4
Top countries
US 4
HS-351 satellites
Track any of them live in KeepTrack.
| Name | NORAD | COSPAR | Owner | Launched | Orbit | Status | Track |
|---|---|---|---|---|---|---|---|
| ESIAFI 1 (COMSTAR 4) Comstar 204 | 12309 | 1981-018A | COM | Feb 21, 1981 | 1436 min, 8.6° | Inactive | ◉ |
| COMSTAR 3 Comstar 203 | 10975 | 1978-068A | COM | Jun 29, 1978 | 1452 min, 9.5° | Inactive | ◉ |
| COMSTAR 2 Comstar 202 | 09047 | 1976-073A | COM | Jul 22, 1976 | 1440 min, 7.9° | Inactive | ◉ |
| COMSTAR 1 Comstar 201 | 08838 | 1976-042A | COM | May 13, 1976 | 1443 min, 7.9° | Inactive | ◉ |
Frequently asked questions
How many HS-351 satellites are there?
The catalog lists 4 objects built on the HS-351 bus. 4 are in orbit and 0 have reentered.
How many HS-351 satellites are in orbit?
4 HS-351 objects are currently in orbit, of which 0 carry an active status.
Who builds the HS-351 bus?
The HS-351 bus is most commonly built by HSES.
When did the first HS-351 satellite launch?
The first cataloged HS-351 satellite launched in 1976, and the most recent in 1981.