- Communications satellite
- Military
- TACSAT 4
- NORAD 37818
- 2011-052A
- Highly elliptical orbit
Current orbit
View on live mapOrbit began over the Atlantic Ocean
Orbit ends over the Atlantic Ocean
Sunlit since
Enters the Earth’s shadow
In view from you
Nobody watches TacSat-4 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 TacSat-4, 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 too faint for the naked eye. What reaches you from it reaches a dish or an antenna, not an eye.
Timeline
- Launch
Launched, on the day GCAT records. Source
Summary
Over the Atlantic Ocean LIVE
Where is TacSat-4?
At 6:20:50 PM UTC TacSat-4 was over the Atlantic Ocean (53.5° S, 14° E), 413 km up, moving at 9.27 km/s and in sunlight.
What is TacSat-4?
A communications satellite in a highly elliptical orbit, in space since Sep 27, 2011.
Can I see TacSat-4?
No, not with the naked eye: no brightness has been published for TacSat-4, and nothing here estimates one; the dishes and receivers on the ground use its signals instead.
General
- Operator
- Naval Research Lab
- State
- United States of America
- Built by
- Naval Research Lab
- What it is
- Communications satellite
- Military
- Yes: a defence organisation flies it
- Launched
- Mass
- 460 kg
- Operating
- No: its regular operations have ended
- Orbit class
- Highly elliptical orbit
From GCAT, Jonathan McDowell’s general catalogue, licensed CC BY 4.0: the operator, the state, the manufacturer, what it is for, that a defence organisation flies it, the launch day, the mass, and whether it is operating. The orbit class is read from its current elements.
Latest orbital data
- Position received
- 6:20 PM UTC
- Station time (UTC)
- 6:20 PM UTC
- Latitude / longitude
- 53.5° S, 14° E
- Altitude
- 413 km
- Speed
- 9.27 km/s (33,365 km/h)
- Course
- north-east
- Light
- In sunlight until 6:27 PM UTC
- Inclination
- 62.9°
- Orbital period
- 233.8 minutes
- Orbits per day
- 6.16
- This orbit
- 370 to 12,013 km
- In shadow
- 38 minutes of each orbit
- In view from
- Within 1,370 km of the point below it
- Elements epoch
- Nov 7, 2026, 11:27 AM, 1 day old
- Source
- Position from Space-Track orbital elements of Nov 7, 2026, 11:27 AM, 1 day old.
No operator publishes an ephemeris for TacSat-4, so every position here comes from its orbital elements.
In orbit
- Close approaches
- No close approach to TacSat-4 has been reported publicly in the past thirty days.
From Space-Track’s public conjunction messages; the latest report was issued Nov 8, 2026, 1:11 PM, 3 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
| Satellite | Typical altitude | Orbital period | Mass | In space since |
|---|---|---|---|---|
| TacSat-4 | 370 to 12,013 km | 234 minutes | 460 kg | 2011 |
| BlueWalker 3 | 443 to 453 km | 94 minutes | about 1.5 t | 2022 |
| Hispasat 30W-6 | 35,786 to 35,786 km | 1,436 minutes | about 6.1 t | 2018 |
| Amazonas Nexus | 35,786 to 35,786 km | 1,436 minutes | about 4.1 t | 2023 |
| ARSAT-1 | 35,786 to 35,786 km | 1,436 minutes | about 3 t | 2014 |
| Astra 1N | 35,786 to 35,786 km | 1,436 minutes | about 5.3 t | 2011 |
Data and API
The current elements from Space-Track as an OMM object, epoch Nov 7, 2026, 11:27 AM, 1 day old.
{
"OBJECT_NAME": "TACSAT 4",
"OBJECT_ID": "2011-052A",
"EPOCH": "2026-11-07T11:27:11.670624",
"MEAN_MOTION": 6.15972917,
"ECCENTRICITY": 0.46313535,
"INCLINATION": 62.8623,
"RA_OF_ASC_NODE": 21.5684,
"ARG_OF_PERICENTER": 288.2095,
"MEAN_ANOMALY": 27.9071,
"EPHEMERIS_TYPE": 0,
"CLASSIFICATION_TYPE": "U",
"NORAD_CAT_ID": 37818,
"ELEMENT_SET_NO": 999,
"REV_AT_EPOCH": 33361,
"BSTAR": 0.0014822358,
"MEAN_MOTION_DOT": 0.0000416,
"MEAN_MOTION_DDOT": 0
}