Transit
Operated by US Navy
Data current as of 2026-07-20.
Transit was the first operational satellite navigation system, built for the US Navy to fix the positions of ships and submarines. It served from the 1960s until GPS superseded it, and pioneered the Doppler navigation later refined by modern systems.
Transit accounts for 92 cataloged objects, of which 14 are in orbit and 0 are active. 78 have reentered. The first launched in 1960, the most recent in 2019. The busiest year was 2004, with 8 added. Most fly near a 90-degree inclination with an orbital period around 107 minutes.
14
In orbit
0
Active
92
Total launched
78
Reentered
Transit launched per year
Still in orbit Since reentered Click a year to list its satellites.
Typical specifications
Most common values across cataloged Transit satellites.
| Manufacturer | APL |
|---|---|
| Purpose | Navigation |
| Launch mass | 59 kg |
| Dry mass | 59 kg |
| Length | 0.9 m |
| Diameter | 0.5 m |
| Span | 0.9 m |
| Shape | Sphere |
| Power | SNAP-9A RTG |
| Propulsion | ? |
| Design life | Operated until 1964, with transmissions ceasing due to radiation damage from the Starfish Prime nuclear test. |
| Equipment | ? |
| Typical orbit | 107 min period, 90° inclination |
Spacecraft buses
The platforms Transit satellites are built on.
Launched on
Transit satellites
Track any of them live in KeepTrack.
| Name | NORAD | COSPAR | Bus | Launched | Orbit | Status | Track |
|---|---|---|---|---|---|---|---|
| TRANSIT 20 DEB deb NNS O-20 | 44565 | 1973-081E | · | Sep 1, 2019 | 105 min, 89.9° | Inactive | ◉ |
| TRANSIT 16 DEB NNS O-13 insulation | 38530 | 1967-048H | · | Jun 1, 2012 | 94 min, 89.6° | Reentered | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 38523 | 1966-005N | · | Jun 1, 2012 | 93 min, 90.0° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 38522 | 1963-038R | · | Jun 1, 2012 | 96 min, 90.0° | Reentered | ◉ |
| TRANSIT 18 DEB NNS O-18 insulation | 42668 | 1968-012G | · | Jun 1, 2009 | 94 min, 89.9° | Reentered | ◉ |
| TRANSIT 18 DEB NNS O-18 insulation | 35416 | 1968-012F | · | Jun 1, 2009 | 106 min, 90.0° | Inactive | ◉ |
| TRANSIT 13 DEB NNS O-9 insulation | 42667 | 1966-041J | · | Apr 1, 2007 | 95 min, 90.1° | Reentered | ◉ |
| TRANSIT 15 DEB NNS O-12 insulation | 29276 | 1967-034L | · | May 1, 2006 | 94 min, 90.2° | Reentered | ◉ |
| TRANSIT 15 DEB NNS O-12 insulation | 29265 | 1967-034K | · | May 1, 2006 | 96 min, 90.1° | Reentered | ◉ |
| TRANSIT 15 DEB NNS O-12 insulation | 29180 | 1967-034J | · | May 1, 2006 | 95 min, 90.1° | Reentered | ◉ |
| TRANSIT 14 DEB NNS O-10 insulation | 29138 | 1966-076J | · | May 1, 2006 | 92 min, 88.7° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 43290 | 1964-083U | · | May 1, 2004 | 93 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 43289 | 1964-083T | · | May 1, 2004 | 94 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 41927 | 1964-083S | · | May 1, 2004 | 93 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 38527 | 1964-083R | · | May 1, 2004 | 93 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 38526 | 1964-083Q | · | May 1, 2004 | 93 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 38525 | 1964-083P | · | May 1, 2004 | 92 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 38524 | 1964-083N | · | May 1, 2004 | 92 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 2 | 28248 | 1964-083M | · | May 1, 2004 | 93 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 27479 | 1963-038P | · | Jul 1, 2002 | 94 min, 90.0° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 26912 | 1965-048Q | · | Sep 1, 2001 | 95 min, 90.1° | Reentered | ◉ |
| TRANSIT 16 DEB NNS O-13 insulation | 33508 | 1967-048G | · | Aug 1, 2000 | 92 min, 89.5° | Reentered | ◉ |
| TRANSIT 14 DEB NNS O-10 insulation | 26817 | 1966-076H | · | Jul 1, 2000 | 105 min, 88.8° | Inactive | ◉ |
| TRANSIT 16 DEB NNS O-13 insulation | 26531 | 1967-048F | · | Aug 1, 2000 | 92 min, 89.6° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 24811 | 1965-048N | · | Jan 1, 1999 | 106 min, 90.1° | Reentered | ◉ |
| TRANSIT 5B-2 DEB deb Transit VBN-2 | 42666 | 1963-049P | · | Jan 9, 1998 | 94 min, 89.8° | Reentered | ◉ |
| TRANSIT 10 DEB NNS O-6 insulation | 25576 | 1965-109F | · | Dec 1, 1998 | 92 min, 89.0° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 25408 | 1967-092L | · | Jul 1, 1998 | 90 min, 89.2° | Reentered | ◉ |
| TRANSIT 5B-2 DEB deb Transit VBN-2 | 25156 | 1963-049N | · | Jan 9, 1998 | 106 min, 89.9° | Inactive | ◉ |
| TRANSIT 9 DEB Transit VC insulation | 25056 | 1964-026J | · | Nov 1, 1997 | 92 min, 90.4° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 24807 | 1967-092K | · | May 1, 1997 | 90 min, 89.1° | Reentered | ◉ |
| TRANSIT 10 DEB NNS O-6 insulation | 24705 | 1965-109E | · | Dec 1, 1996 | 102 min, 89.1° | Inactive | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 24704 | 1966-005M | · | Oct 1, 1996 | 92 min, 89.9° | Reentered | ◉ |
| TRANSIT 9 DEB Transit VC insulation | 24272 | 1964-026H | · | Jul 1, 1996 | 92 min, 90.5° | Reentered | ◉ |
| TRANSIT 16 DEB NNS O-13 insulation | 23562 | 1967-048E | · | Apr 1, 1995 | 91 min, 89.5° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 26815 | 1965-048P | · | 1994 | 91 min, 90.0° | Reentered | ◉ |
| TRANSIT 15 DEB NNS O-12 insulation | 22172 | 1967-034H | · | Oct 1, 1992 | 96 min, 90.0° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 21945 | 1965-048M | · | Jun 1, 1991 | 92 min, 90.0° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 20652 | 1967-092J | · | May 1, 1990 | 93 min, 89.2° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 20470 | 1963-038N | · | Jan 30, 1990 | 89 min, 90.0° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 20009 | 1967-092H | · | May 1, 1989 | 92 min, 89.1° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 19838 | 1965-048L | · | May 1, 1988 | 105 min, 90.0° | Reentered | ◉ |
| TRANSIT 16 DEB NNS O-13 insulation | 19222 | 1967-048D | · | May 1, 1988 | 91 min, 89.5° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 19062 | 1963-038M | · | Apr 1, 1988 | 96 min, 89.8° | Reentered | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 19366 | 1966-005L | · | Apr 1, 1986 | 99 min, 89.8° | Reentered | ◉ |
| TRANSIT 16 DEB NNS O-13 insulation | 17723 | 1967-048C | · | Apr 1, 1986 | 104 min, 98.9° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 17176 | 1967-092G | · | Aug 1, 1986 | 92 min, 89.1° | Reentered | ◉ |
| TRANSIT 18 DEB NNS O-18 insulation | 18594 | 1968-012E | · | Mar 1, 1985 | 102 min, 71.0° | Reentered | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 15341 | 1966-005K | · | Oct 1, 1983 | 91 min, 89.7° | Reentered | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 14226 | 1966-005J | · | Oct 1, 1982 | 93 min, 89.7° | Reentered | ◉ |
| TRANSIT 9 DEB Transit VC insulation | 13360 | 1964-026G | · | Jun 1, 1982 | 92 min, 90.4° | Reentered | ◉ |
| TRANSIT 5B-1 DEB Transit VBN-1 part | 12943 | 1963-038L | · | Nov 1, 1981 | 104 min, 90.1° | Reentered | ◉ |
| TRANSIT 12 DEB NNS O-8 insulation | 12856 | 1966-024F | · | Jul 1, 1981 | 93 min, 89.7° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 12555 | 1967-092F | · | May 1, 1981 | 104 min, 89.2° | Reentered | ◉ |
| TRANSIT 17 DEB NNS O-14 insulation | 12554 | 1967-092E | · | May 1, 1981 | 98 min, 89.2° | Reentered | ◉ |
| TRANSIT 9 DEB Transit VC insulation | 12142 | 1964-026F | · | Dec 1, 1980 | 97 min, 90.4° | Reentered | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 11991 | 1966-005H | · | Sep 1, 1980 | 104 min, 90.2° | Inactive | ◉ |
| TRANSIT 11 DEB NNS O-7 insulation | 11990 | 1966-005G | · | Sep 1, 1980 | 101 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 11953 | 1965-048H | · | Aug 25, 1980 | 93 min, 89.9° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 11952 | 1965-048G | · | Aug 25, 1980 | 92 min, 89.9° | Reentered | ◉ |
| TRANSIT 5B-7 DEB deb NNS O-5 | 11855 | 1965-065T | · | Jun 1, 1980 | 92 min, 89.9° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 12582 | 1965-048K | · | Sep 1, 1978 | 98 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B-6 DEB deb NNS O-4 | 12516 | 1965-048J | · | Jan 1, 1976 | 97 min, 89.9° | Reentered | ◉ |
| TRANSIT 14 DEB NNS O-10 insulation | 09401 | 1966-076G | · | Aug 1, 1976 | 93 min, 88.8° | Reentered | ◉ |
| TRANSIT 14 DEB NNS O-10 insulation | 08000 | 1966-076F | · | Jun 1, 1975 | 98 min, 88.8° | Reentered | ◉ |
| TRANSIT 15 DEB NNS O-12 insulation | 07670 | 1967-034G | · | Jan 1, 1975 | 99 min, 90.2° | Reentered | ◉ |
| TRANSIT 14 DEB NNS O-10 insulation | 07558 | 1966-076E | · | Nov 1, 1974 | 94 min, 88.8° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 07259 | 1963-038K | · | Apr 10, 1974 | 100 min, 89.8° | Reentered | ◉ |
| TRANSIT 5A DEB deb Transit VA-1 | 07258 | 1962-071E | · | Mar 1, 1974 | 92 min, 90.6° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 04587 | 1963-038J | · | Sep 1, 1970 | 96 min, 89.8° | Reentered | ◉ |
| TRANSIT 12 DEB NNS O-8 insulation | 03590 | 1966-024E | · | Jul 1, 1968 | 97 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B2-5E3 DEB deb Transit | 06283 | 1963-049M | · | Jul 1, 1967 | 98 min, 89.7° | Reentered | ◉ |
| TRANSIT 5B2-5E3 DEB deb Transit | 06182 | 1963-049L | · | Jul 1, 1967 | 93 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B2-5E3 DEB deb Transit | 04586 | 1963-049K | · | Jul 1, 1967 | 98 min, 89.7° | Reentered | ◉ |
| TRANSIT 5B-2 DEB deb Transit VBN-2 | 02930 | 1963-049J | · | Jul 1, 1967 | 95 min, 89.8° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 1 | 05540 | 1964-083L | · | Dec 1, 1966 | 97 min, 89.7° | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 1 | 05444 | · | · | Dec 1, 1966 | · | Reentered | ◉ |
| TRANSIT 5E-5 DEB deb VE-5 event 1 | 02798 | 1964-083J | · | Dec 1, 1966 | 100 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B-1 DEB deb Transit VBN-1 | 01528 | 1963-038F | · | Apr 1, 1966 | 98 min, 89.8° | Reentered | ◉ |
| TRANSIT 5B-7 DEB deb NNS O-5 | 03809 | 1965-065N | · | Aug 13, 1965 | 99 min, 89.9° | Reentered | ◉ |
| TRANSIT 5B-1 DEB Transit VBN-1 part | 03166 | 1963-038H | · | Sep 28, 1963 | 107 min, 90.0° | Inactive | ◉ |
| TRANSIT 5B-1 DEB Transit VBN-1 launch debris | 02097 | 1963-038G | · | Sep 28, 1963 | 105 min, 90.0° | Inactive | ◉ |
| TRANSIT 5E-3 Transit VE-3 | 00705 | 1963-049C | Transit 5 | Dec 5, 1963 | 107 min, 89.9° | Inactive | ◉ |
| TRANSIT 5B-2 Transit VBN-2 | 00704 | 1963-049B | Transit 5 | Dec 5, 1963 | 107 min, 89.9° | Inactive | ◉ |
| TRANSIT 5B-1 Transit VBN-1 | 00670 | 1963-038B | Transit 5 | Sep 28, 1963 | 107 min, 90.0° | Inactive | ◉ |
| TRANSIT 5A-3 Transit VA-3 | 00594 | 1963-022A | Transit 5 | Jun 16, 1963 | 88 min, 89.8° | Reentered | ◉ |
| TRANSIT 5A Transit VA-1 | 00509 | 1962-071A | Transit 5 | Dec 19, 1962 | 88 min, 90.6° | Reentered | ◉ |
| TRANSIT 4B Transit IV-B | 00202 | 1961-031A | Transit 4 | Nov 15, 1961 | 106 min, 32.4° | Inactive | ◉ |
| TRANSIT 4A Transit IV-A | 00116 | 1961-015A | Transit 4 | Jun 29, 1961 | 103 min, 66.8° | Inactive | ◉ |
| TRANSIT 3B & LOFTI 1 Transit III-B | 00087 | 1961-007A | Transit 1 | Feb 22, 1961 | 88 min, 28.4° | Reentered | ◉ |
| TRANSIT 2A Transit II-A | 00045 | 1960-007A | Transit | Jun 22, 1960 | 100 min, 66.7° | Inactive | ◉ |
| TRANSIT 1B Transit I-B | 00031 | 1960-003B | Transit 1 | Apr 13, 1960 | 89 min, 51.2° | Reentered | ◉ |
Frequently asked questions
How many Transit satellites are in orbit?
14 Transit objects are currently in orbit, out of 92 ever cataloged. 78 have reentered.
How many Transit satellites are active?
0 Transit satellites carry an active status in the catalog.
When did the first Transit satellite launch?
The first cataloged Transit object launched in 1960, and the most recent in 2019.
Who operates Transit?
Transit is operated by US Navy.
How can I track Transit satellites?
You can track the Transit fleet live in the KeepTrack 3D tracker, or open any individual satellite from the list on this page.