- Navigation satellite
- Military
- NORAD 43873
- 2018-109A
- Medium Earth orbit
Current orbit
View on live mapOrbit began over the Pacific Ocean
Orbit ends over the Indian Ocean
In view from you
Nobody watches NAVSTAR 77 (USA 289) go over, but a receiver still asks whether it is above the horizon. Say where you are and this card answers.
Your position is rounded to about a kilometre and sent only to the Orbinauts API, to find the pass.
No brightness has been published for NAVSTAR 77 (USA 289), so it is not a naked-eye satellite and no city page carries pass times for it. Nothing here estimates one.
Seeing it
There is nothing to go outside for: it is far too high and too faint for the naked eye. What you notice of it is a position fix, and the card above says whether it is above your horizon to give you one.
Timeline
Summary
Over Algeria LIVE
Where is NAVSTAR 77 (USA 289)?
At 4:09:13 AM UTC NAVSTAR 77 (USA 289) was over Algeria (31.2° N, 6.2° E), 20,285 km up, moving at 3.86 km/s and in sunlight.
What is NAVSTAR 77 (USA 289)?
A GPS navigation satellite in medium Earth orbit, in space since Dec 23, 2018.
Can I see NAVSTAR 77 (USA 289)?
No, not with the naked eye: no brightness has been published for NAVSTAR 77 (USA 289), and nothing here estimates one; receivers on the ground use its signals instead, whenever it is above their horizon.
General
NAVSTAR 77 (USA 289) is one of the 32 navigation satellites of the GPS constellation. See every GPS satellite and how many are above you right now.
- Launched
- Known to its operator as
- PRN 4
- Space vehicle number
- 74
- Clock in use
- Rubidium
- Generation
- GPS Block III
- Signals
- L1 C/A, P(Y) on L1 and L2, L2C, M-code, L5, and L1C
- Design life
- 15 years
- Built by
- Lockheed Martin
- Typical altitude
- 20,000 to 20,400 km
Latest orbital data
- Position received
- 4:09 AM UTC
- Station time (UTC)
- 4:09 AM UTC
- Latitude / longitude
- 31.2° N, 6.2° E
- Altitude
- 20,285 km
- Speed
- 3.86 km/s (13,896 km/h)
- Course
- north
- Light
- In sunlight
- Inclination
- 55.8°
- Orbital period
- 718 minutes
- Orbits per day
- 2.01
- This orbit
- 20,072 to 20,291 km
- In shadow
- None of this orbit
- In view from
- Within 7,380 km of the point below it
- Elements epoch
- Nov 1, 2026, 8:41 PM, 1 day old
- Source
- Position from Space-Track orbital elements of Nov 1, 2026, 8:41 PM, 1 day old.
No operator publishes an ephemeris for NAVSTAR 77 (USA 289), so every position here comes from its orbital elements.
In service
A receiver can count on it now.
- Usable now
- Yes: its operator has published no outage in force.
- Plane and slot
- Plane F, slot 4
- In service since
- Jan 13, 2020 Notice
- Age against design life
- 6.8 of the 15 years it was built to last
- Last outage
- Oct 16, 2025, 6:15 PM to Oct 17, 2025, 2:48 AM, forecast Notice
From GPS’s own notices, as its operator published them on Oct 30, 2026, 3:06 AM.
In orbit
- Close approaches
- No close approach to NAVSTAR 77 (USA 289) has been reported publicly in the past thirty days.
From Space-Track’s public conjunction messages; the latest report was issued Nov 2, 2026, 1:53 PM, 14 hours old. Only approaches serious enough to be reported publicly are listed: within three days and, for two bodies near the Earth, closer than a kilometre with a chance of a collision above 1 in 10,000, the level at which NASA moves the ISS.
Beside the others
| Constellation | Satellites | Typical altitude | Orbital period | Planes | Operator |
|---|---|---|---|---|---|
| GPS | 32 | 20,000 to 20,400 km | 718 minutes | 6 | The United States Space Force |
| Galileo | 28 | 23,100 to 23,300 km | 845 minutes | — | EUSPA, the European Union Agency for the Space Programme |
| BeiDou | 37 | 21,450 to 21,600 km | 773 minutes | — | The China Satellite Navigation Office |
| GLONASS | 24 | 19,050 to 19,200 km | 676 minutes | — | Roscosmos, the Russian State Space Corporation |
Data and API
The current elements from Space-Track as an OMM object, epoch Nov 1, 2026, 8:41 PM, 1 day old.
{
"OBJECT_NAME": "NAVSTAR 77 (USA 289)",
"OBJECT_ID": "2018-109A",
"EPOCH": "2026-11-01T20:41:39.873120",
"MEAN_MOTION": 2.00566352,
"ECCENTRICITY": 0.00412235,
"INCLINATION": 55.7771,
"RA_OF_ASC_NODE": 86.7576,
"ARG_OF_PERICENTER": 196.8601,
"MEAN_ANOMALY": 335.5637,
"EPHEMERIS_TYPE": 0,
"CLASSIFICATION_TYPE": "U",
"NORAD_CAT_ID": 43873,
"ELEMENT_SET_NO": 999,
"REV_AT_EPOCH": 5783,
"BSTAR": 0,
"MEAN_MOTION_DOT": 3.5e-7,
"MEAN_MOTION_DDOT": 0
}