OPS 3674 (VELA 4), 837
Orbit data source: Space-Track
OPS 3674 (VELA 4), 837 is a payload satellite owned by USAF SSD (US) in HEO that was launched on Fri, 17 Jul 1964 UTC via an ATLAS AGENA D launch vehicle from the Air Force Eastern Test Range (AFETR). Payload-class satellites include a variety of spacecraft equipped with specific instruments for various scientific and technological missions. These include communications satellites like Starlink; space stations such as the ISS; scientific satellites like the Hubble; Earth observation satellites from companies like Planet Labs, Umbra, and HawkEye 360; GPS; miniature CubeSats for education and research; and military/defense satellites.
Focus sentinelFocus sentinel
Embed this page
Focus sentinelFocus sentinel
837 intel report (Beta)
Focus sentinelFocus sentinel
Create New Watchlist
Focus sentinelFocus sentinel
Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
TRW
Mission
Defense Early Warn
Bus & Motor
VELA, BE-3
Mass
~217 kg wet, 125 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Poly, 0.7 m
Radar Cross Section
2.240 m², Medium (>0.1 m² and < 1m²)
Expand to show TLE details & historyLast TLE update: in 3 days
TLE from in 3 days
0 OPS 3674 (VELA 4)
1 00837U 64040B 25262.92162981 -.00000043 00000-0 00000-0 0 9995
2 00837 48.8122 128.5457 4989559 257.8266 0.6792 0.24001943 54075Epoch: 2025-09-19T22:07Z
TLE epoch observation values (Epoch: 2025-09-19T22:07:08.815Z)
Latitude
-47.74364°
Longitude
51.64862°
Altitude
47,975.12 km
Speed
3.32 km/s
True Right ascension
01h 29m 59s
True Declination
-47° 43' 16"
Sunlit
Visualization orbit readout
Latitude
Unknown
Longitude
Unknown
Altitude
Unknown
Speed
Unknown
Apparent Right ascension
Unknown
Apparent Declination
Unknown
Sunlit
Visualization observer readout
Local Sidereal Time
17:36:26
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
157,565.186 km
Perigee altitude
48,421.897 km
Semi-major axis
109,371.679 km
Eccentricity
0.49896
Inclination
48.8122°
RAAN
128.5457°
Arg. of periapsis
257.8266°
True anomaly
2.34422°
Mean anomaly
0.6792°
Eccentric anomaly
1.35544°
Mean motion
0.06 °/min
Orbital period
5,999.52 mins
BSTAR
0
Loading maneuver chart data...
Computing Atmospheric mass density...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Other satellites on launch #40 in the year 1964 (1964-07-17 UTC)
Did you know?
You can import UDL-sourced sensor .json files into the Sandbox to generate a visibility chart that accounts for multi-vendor sensor geometry.OPS 3674 (VELA 4) Visibility forecast
Loading observer location...
Span | Click to sort rows by Start time (UTC) header in descending order | Start Az. | Max El. time (UTC) | Max El. Az. | Max El. | End time (UTC) | End Az. |
|---|---|---|---|---|---|---|---|
| 25 mins | 2025-09-17 00:52:02.075Z | 302.073° NW | 2025-09-17 00:52:02.075Z | 302.073° NW | 13.125° | 2025-09-17 01:17:02.075Z | 305.389° NW |
| 773 mins | 2025-09-17 11:59:02.075Z | 42.762° NE | 2025-09-17 20:38:02.075Z | 0.249° NNE | 44.722° | 2025-09-18 00:52:02.075Z | 301.475° NW |
Co-orbital & Co-planar RSOs
Thresholds — Semi-major Axis: ±100 km, RAAN: ±3°, Inclination: ±5°
TCA is derived from TLE conjunctions
Click to sort rows by RSO header in ascending order | Click to sort rows by Country header in ascending order | Click to sort rows by Type header in ascending order | Click to sort rows by Inclination Δ header in ascending order | Click to sort rows by RAAN Δ header in ascending order | Click to sort rows by Coplanar Angle header in ascending order | Click to sort rows by SMA Δ header in ascending order | Click to sort rows by Orbital period header in ascending order | Click to sort rows by <5km Md TCA header in ascending order |
|---|
CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
Authenticating...
Click to sort rows by Secondary header in ascending order | Click to sort rows by Secondary name header in ascending order | Click to sort rows by Country header in ascending order | Click to sort rows by Owner header in ascending order | Click to sort rows by Obj. Type header in ascending order | Click to sort rows by Miss dist. header in ascending order | Click to sort rows by Rel. speed header in ascending order | Click to sort rows by Apr. angle header in ascending order | Click to sort rows by TCA header in ascending order |
|---|