RELAY 2, 737
Orbit data source: Space-Track
RELAY 2, 737 is a payload satellite owned by GSFC (US) that was launched on Tue, 21 Jan 1964 UTC via a THOR DELTA B 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.
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737 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
RCA/East Windsor
Mission
Civil Communications
Bus & Motor
RELAY, Unknown motor
Mass
83 kg wet, 83 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Oct Cyl, 0.4 m
Radar Cross Section
0.652 m², Medium (>0.1 m² and < 1m²)
Expand to show TLE details & historyLast TLE update: 18 hours ago
TLE from 18 hours ago
0 RELAY 2
1 00737U 64003A 25259.07023078 -.00000025 00000-0 00000-0 0 9998
2 00737 46.4561 294.2553 2599533 73.7900 313.1015 7.39533957665818Epoch: 2025-09-16T01:41Z
TLE epoch observation values (Epoch: 2025-09-16T01:41:07.939Z)
Latitude
0.00002°
Longitude
-86.29357°
Altitude
3,293.583 km
Speed
6.828 km/s
True Right ascension
19h 37m 01s
True Declination
0° 00' 00"
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
12:24:44
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
7,644.214 km
Perigee altitude
1,858.037 km
Semi-major axis
11,129.262 km
Eccentricity
0.25995
Inclination
46.4561°
RAAN
294.2553°
Arg. of periapsis
73.79°
True anomaly
286.27503°
Mean anomaly
313.1015°
Eccentric anomaly
300.23313°
Mean motion
1.8486 °/min
Orbital period
194.74 mins
BSTAR
0
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Other satellites on launch #3 in the year 1964 (1964-01-21 UTC)
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You can import UDL-sourced sensor .json files into the Sandbox to generate a visibility chart that accounts for multi-vendor sensor geometry.RELAY 2 Visibility forecast
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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. |
|---|---|---|---|---|---|---|---|
| 21 mins | 2025-09-17 03:40:12.113Z | 196.757° SSW | 2025-09-17 03:53:12.113Z | 133.369° SE | 31.029° | 2025-09-17 04:01:12.113Z | 75.093° E |
| 19 mins | 2025-09-17 07:09:12.113Z | 259.873° W | 2025-09-17 07:18:12.113Z | 336.682° NNW | 43.451° | 2025-09-17 07:28:12.113Z | 67.656° E |
| 25 mins | 2025-09-17 10:37:12.113Z | 296.211° NW | 2025-09-17 10:45:12.113Z | 3.013° NNE | 44.619° | 2025-09-17 11:02:12.113Z | 112.965° SE |
| 30 mins | 2025-09-17 14:03:12.113Z | 278.932° WNW | 2025-09-17 14:13:12.113Z | 222.386° SW | 30.185° | 2025-09-17 14:33:12.113Z | 168.918° S |
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 |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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