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
Spacecraft
Bus & Motor
RELAY, Unknown motor
Mass
83 kg wet, 83 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Unknown
Radar Cross Section
Medium (>0.1 m² and <1 m²)
Expand to show TLE details & historyLast TLE update: 1 day ago
TLE from 1 day ago
0 RELAY 2
1 00737U 64003A 25292.99722601 -.00000024 00000-0 00000-0 0 9993
2 00737 46.4510 256.0381 2598187 111.8568 277.6861 7.39533951668321Epoch: 2025-10-19T23:56Z
TLE epoch observation values (Epoch: 2025-10-19T23:56:00.327Z)
Latitude
0.00003°
Longitude
-131.6691°
Altitude
5,107.169 km
Speed
5.797 km/s
True Right ascension
17h 04m 09s
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
22:14:49
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
7,642.716 km
Perigee altitude
1,859.535 km
Semi-major axis
11,129.263 km
Eccentricity
0.25982
Inclination
46.451°
RAAN
256.0381°
Arg. of periapsis
111.8568°
True anomaly
248.2049°
Mean anomaly
277.6861°
Eccentric anomaly
262.91331°
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 | 2025-10-21 05:41:58.845Z | 294.007° NW | 2025-10-21 05:51:58.845Z | 355.623° N | 44.201° | 2025-10-21 06:02:58.845Z | 108.597° ESE |
| 17 mins | 2025-10-21 09:10:58.845Z | 274.437° WNW | 2025-10-21 09:16:58.845Z | 230.435° WSW | 25.533° | 2025-10-21 09:27:58.845Z | 173.615° S |
| 33 mins | 2025-10-21 21:13:58.845Z | 176.503° S | 2025-10-21 21:34:58.845Z | 129.261° SE | 24.569° | 2025-10-21 21:46:58.845Z | 80.737° E |
| 31 mins | 2025-10-22 00:42:58.845Z | 233.588° WSW | 2025-10-22 01:02:58.845Z | 168.456° S | 44.831° | 2025-10-22 01:13:58.845Z | 63.74° ENE |
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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