RELAY 1 (A-15), 503
Orbit data source: Space-Track
RELAY 1 (A-15), 503 is a payload satellite owned by GSFC (US) that was launched on Thu, 13 Dec 1962 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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503 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
78 kg wet, 78 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: 2 days ago
TLE from 2 days ago
0 RELAY 1 (A-15)
1 00503U 62068A 25258.22860852 -.00000014 00000-0 00000-0 0 9991
2 00503 47.5212 56.8993 2837538 245.3060 313.5041 7.78160117784078Epoch: 2025-09-15T05:29Z
TLE epoch observation values (Epoch: 2025-09-15T05:29:11.776Z)
Latitude
7.96258°
Longitude
152.83713°
Altitude
2,883.418 km
Speed
7.003 km/s
True Right ascension
15h 18m 17s
True Declination
7° 55' 35"
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
14:04:56
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
7,432.246 km
Perigee altitude
1,327.105 km
Semi-major axis
10,757.813 km
Eccentricity
0.28375
Inclination
47.5212°
RAAN
56.8993°
Arg. of periapsis
245.306°
True anomaly
283.84874°
Mean anomaly
313.5041°
Eccentric anomaly
299.3303°
Mean motion
1.94517 °/min
Orbital period
185.07 mins
BSTAR
0
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Other satellites on launch #68 in the year 1962 (1962-12-13 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 1 (A-15) 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. |
|---|---|---|---|---|---|---|---|
| 14 mins | 2025-09-16 21:21:07.584Z | 199.253° SSW | 2025-09-16 21:21:07.584Z | 199.253° SSW | 40.665° | 2025-09-16 21:35:07.584Z | 155.087° SSE |
| 74 mins | 2025-09-17 10:58:07.584Z | 186.252° SSW | 2025-09-17 11:28:07.584Z | 116.814° SE | 38.527° | 2025-09-17 12:12:07.584Z | 56.021° ENE |
| 86 mins | 2025-09-17 14:14:07.584Z | 243.046° WSW | 2025-09-17 14:57:07.584Z | 338.464° N | 44.776° | 2025-09-17 15:40:07.584Z | 71.483° E |
| 77 mins | 2025-09-17 17:46:07.584Z | 286.191° WNW | 2025-09-17 18:37:07.584Z | 29.608° NE | 44.705° | 2025-09-17 19:03:07.584Z | 111.9° ESE |
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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