NRL 20 Satellite Bus
Data current as of 2026-07-20.
The NRL 20 bus accounts for 8 cataloged objects, of which 4 are in orbit and 0 are active. 4 have reentered. Most are built by NRL. The largest operator on this bus is National Reconnaissance Office. The first launched in 1960, the most recent in 1965.
4
In orbit
0
Active
8
Total launched
4
Reentered
NRL 20 launched per year
Still in orbit Since reentered Click a year to list its satellites.
Typical specifications
Most common values across cataloged NRL 20 satellites.
| Manufacturer | NRL |
|---|---|
| Purpose | SIGINT |
| Launch mass | 25 kg |
| Dry mass | 25 kg |
| Length | 0.5 m |
| Diameter | 0.5 m |
| Span | 0.5 m |
| Shape | Sphere |
| Power | Solar cells, batteries |
| Propulsion | None |
| Design life | ca. 34 month (average) |
| Equipment | TR-17 SECOR transponder (#(1)); TR-27 SECOR transponder (#5) |
| Typical orbit | 103 min period, 70° inclination |
Top operators
Top countries
US 8
NRL 20 satellites
Track any of them live in KeepTrack.
| Name | NORAD | COSPAR | Owner | Launched | Orbit | Status | Track |
|---|---|---|---|---|---|---|---|
| SECOR 5 (EGRS 5) EGRS V | 01506 | 1965-063A | ACE/GIMR | Aug 10, 1965 | 122 min, 69.2° | Inactive | ◉ |
| GREB GREB | 00731 | 1964-001E | NRO/NRL | Jan 11, 1964 | 103 min, 69.9° | Inactive | ◉ |
| GGSE 1 (GGRS) GGSE 1 | 00728 | 1964-001B | NRO/NRL | Jan 11, 1964 | 103 min, 69.9° | Inactive | ◉ |
| LOFTI 2A Lofti IIB | 00601 | 1963-021B | NRL | Jun 15, 1963 | 88 min, 69.9° | Reentered | ◉ |
| FTV 1292 NRL PL112 | 00598 | 1963-021E | NRO/NRL | Jun 15, 1963 | 89 min, 69.9° | Reentered | ◉ |
| CALSPHERE 1A NRL PL121 | 00513 | 1962-067E | NRO/NRL | Dec 13, 1962 | 88 min, 70.2° | Reentered | ◉ |
| BLACK SPHERE NRL PL120 | 00502 | 1962-067A | NRO/NRL | Dec 13, 1962 | 89 min, 70.2° | Reentered | ◉ |
| SOLRAD 1 (GREB) GRAB 1 | 00046 | 1960-007B | Naval Research Laboratory | Jun 22, 1960 | 99 min, 66.7° | Inactive | ◉ |
Frequently asked questions
How many NRL 20 satellites are there?
The catalog lists 8 objects built on the NRL 20 bus. 4 are in orbit and 4 have reentered.
How many NRL 20 satellites are in orbit?
4 NRL 20 objects are currently in orbit, of which 0 carry an active status.
Who builds the NRL 20 bus?
The NRL 20 bus is most commonly built by NRL.
When did the first NRL 20 satellite launch?
The first cataloged NRL 20 satellite launched in 1960, and the most recent in 1965.