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Current satellite positions
SatelliteLatitudeLongitude
MMS 3
SeekSat

MMS 3

launched 2015highly elliptical orbitNORAD 40484 · 2015-011C

Height
86,662.0 km
From center
93,035.9 km
Sunlight
Sunlit
Speed
2.118 km/s
Ground speed
0.396 km/s
Over
26.465° N, 46.696° W

Passes

Technical details

Mean elements

Elements are 9 hours old, from CelesTrak GP data (groups: active), fetched 2 h ago.How accurate is this?

Perigee
11,006 km
Apogee
171,394 km
Period
5,055.77 min (3 d 12 h)
Inclination
73.20°
Eccentricity
0.8218
Semi-major axis
97,578.0 km
Epoch
2026-11-15T14:00:01Z

Orbit diagram

perigeeapogee
Drawn to scale in the orbit's own plane, from mean elements. Earth's center is at one focus.

Orbit check

The live speed and distance fit this orbit to within 0.003%.

Vis-viva: v²r/GM = 1.0466 and 2 − r/a = 1.0465

Raw elements

2LE

1 40484U 15011C   26319.58335647 -.00000322  00000+0  00000+0 0  9996
2 40484  73.1985 347.1055 8218454 170.5848 281.8380  0.28481917  1365

3LE

MMS 3
1 40484U 15011C   26319.58335647 -.00000322  00000+0  00000+0 0  9996
2 40484  73.1985 347.1055 8218454 170.5848 281.8380  0.28481917  1365

OMM

{
  "OBJECT_NAME": "MMS 3",
  "OBJECT_ID": "2015-011C",
  "EPOCH": "2026-11-15T14:00:01.999008",
  "MEAN_MOTION": 0.28481917,
  "ECCENTRICITY": 0.8218454,
  "INCLINATION": 73.1985,
  "RA_OF_ASC_NODE": 347.1055,
  "ARG_OF_PERICENTER": 170.5848,
  "MEAN_ANOMALY": 281.838,
  "EPHEMERIS_TYPE": 0,
  "CLASSIFICATION_TYPE": "U",
  "NORAD_CAT_ID": 40484,
  "ELEMENT_SET_NO": 999,
  "REV_AT_EPOCH": 136,
  "BSTAR": 0,
  "MEAN_MOTION_DOT": -0.00000322,
  "MEAN_MOTION_DDOT": 0
}

How we compute these

Altitude
Height above the WGS84 ellipsoid, the standard model of Earth's shape, straight below the satellite.
Speed
The length of SGP4's velocity vector in the TEME frame: the inertial speed. It is not the speed over the ground.
Ground speed
How fast the point below the satellite moves across Earth's surface, with Earth's rotation taken out.
From Earth's center
Distance from Earth's center, from SGP4's position.
Latitude and longitude
The point on the WGS84 ellipsoid straight below the satellite, from SGP4's position turned into Earth-fixed coordinates.
Sunlight
How much sunlight reaches the satellite past Earth and its atmosphere. Light grazing Earth is dimmed by air and ozone, bent into the shadow by refraction, and blocked below 10 km (clouds and haze); the Sun's disc is darker at its edge. So the satellite fades over a few seconds in low orbit and a couple of minutes in geostationary orbit, reddening as it goes, rather than switching off. The atmosphere is a clear standard one: haze from a large volcanic eruption can make the real fade come a few seconds early.
Orbit check (vis-viva)
v²r/GM uses the live speed and distance above, with GM = 398,600.4418 km³/s². Vis-viva says it equals 2 − r/a, where a is the mean semi-major axis. They agree as closely as SGP4's mean elements allow, usually within 1%.
Mean elements
Perigee, apogee, period, eccentricity, inclination and semi-major axis are mean elements from the published set, not instantaneous values. Perigee and apogee heights are above Earth's equatorial radius (6,378 km).
Epoch
The epoch is the moment the element set describes. Positions get less accurate the further you are from it.
How accurate is this?
Positions are predictions from the published elements, not live tracking. Through SGP4 they are usually within a kilometre or two near the epoch and drift by a few km a day after it, more for low or manoeuvring satellites. The map shows ground positions, the point straight below the satellite, so dots that look close can be thousands of km apart in height. Good for passes and tracks; not for judging close approaches between objects.
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