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NAVSTAR 81 (USA 319) — Live Satellite Tracking (NORAD 48859)
Track NAVSTAR 81 (USA 319) (NORAD catalog number 48859) live on the WatchSat interactive 3D globe above. Its position is propagated in real time from the latest CelesTrak two-line element set using the SGP4/SDP4 orbital model — the same math professional trackers run. It has been on orbit since 2021, launched on the 54th orbital launch of that year (COSPAR designation 2021-054A). As of this element set it had completed roughly 3,839 revolutions of Earth.
Moving at about 3.88 km/s, NAVSTAR 81 (USA 319) operates in medium Earth orbit at roughly 20,114–20,265 km altitude, taking about 12.0 hours per revolution (2.01 orbits a day). The orbit is essentially circular (eccentricity 0.0028). Inclined 55.1° to the equator, it overflies every latitude up to about 55° north and south. Its orbital plane crosses the equator northbound at right ascension 329.2°.
Orbital elements
| Orbit regime | medium Earth orbit (MEO) |
|---|---|
| Perigee × apogee altitude | ~20,114 km × 20,265 km |
| Inclination | 55.13° |
| Orbital period | 718.0 min (2.01 rev/day) |
| Eccentricity | 0.00284 |
| Element set epoch | 2026-09-06 |
| COSPAR designation | 2021-054A |
| NORAD catalog number | 48859 |
This page's orbital elements come from the CelesTrak catalog of 2026-09-08. The live 3D view above fetches its own current CelesTrak data when the page opens, through an edge cache that refreshes roughly every 30 minutes.
About the Navigation group
NAVSTAR 81 (USA 319) is part of the US GPS (NAVSTAR) fleet — one of 173 global-navigation satellites in the WatchSat catalog across GPS, GLONASS, Galileo and BeiDou. GNSS spacecraft broadcast precise time signals from orbits around 20,000 km up; a phone fixes its position by comparing several of them at once. See the whole navigation group live in 3D.
Can you see NAVSTAR 81 (USA 319) from the ground?
Not with the naked eye. At its altitude NAVSTAR 81 (USA 319) is far beyond unaided visibility — following satellites this high takes a telescope and good timing. You can still track it precisely in the live 3D view above, or check pass predictions for your location.
Related satellites
Nearest catalog neighbors of NAVSTAR 81 (USA 319) in the Navigation group — usually craft from the same or adjacent launches:
- GSAT0223 (GALILEO 27) (NORAD 49809)
- GSAT0224 (GALILEO 28) (NORAD 49810)
- NAVSTAR 80 (USA 309) (NORAD 46826)
- COSMOS 2547 [GLONASS-K] (NORAD 46805)
- NAVSTAR 79 (USA 304) (NORAD 45854)
- BEIDOU-3 G3 (NORAD 45807)
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