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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Identifier
Orbit
Country
USRelated business
Manufacturer
RCA/East Windsor
Mission
Spacecraft
Bus & Motor
RELAY, Unknown motor
Mass
78 kg wet, 78 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
OCT FRUST, 1.1 m
Radar Cross Section
Medium (>0.1 m² and <1 m²)
Expand to show TLE details & historyLast TLE update: 2 days ago
TLE from 2 days ago
0 RELAY 1 (A-15)
1 00503U 62068A 26258.47170572 -.00000019 00000-0 00000-0 0 9997
2 00503 47.5156 309.9354 2834332 327.8462 26.1442 7.78169402812518Epoch: 2026-09-15T11:19Z
TLE epoch observation values (Epoch: 2026-09-15T11:19:15.374Z)
Latitude
10.53448°
Longitude
155.44222°
Altitude
1,899.469 km
Speed
7.699 km/s
True Right ascension
21h 18m 46s
True Declination
10° 28' 53"
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
02:15:57
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
7,428.688 km
Perigee altitude
1,330.493 km
Semi-major axis
10,757.727 km
Eccentricity
0.28343
Inclination
47.5156°
RAAN
309.9354°
Arg. of periapsis
327.8462°
True anomaly
46.50114°
Mean anomaly
26.1442°
Eccentric anomaly
35.59688°
Mean motion
1.94519 °/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. |
|---|---|---|---|---|---|---|---|
| 72 mins | 2026-09-17 09:48:05.575Z | 280.406° WNW | 2026-09-17 10:10:05.575Z | 3.314° NNE | 73.864° | 2026-09-17 11:00:05.575Z | 99.353° ESE |
| 81 mins | 2026-09-17 13:09:05.575Z | 300.328° NW | 2026-09-17 13:42:05.575Z | 228.479° WSW | 74.002° | 2026-09-17 14:30:05.575Z | 149.123° SSE |
| 60 mins | 2026-09-17 16:35:05.575Z | 295.096° NW | 2026-09-17 17:04:05.575Z | 254.703° W | 25.719° | 2026-09-17 17:35:05.575Z | 210.754° SW |
| 26 mins | 2026-09-18 04:05:05.575Z | 169.804° S | 2026-09-18 04:13:05.575Z | 116.751° SE | 32.683° | 2026-09-18 04:31:05.575Z | 59.883° ENE |
| 50 mins | 2026-09-18 07:16:05.575Z | 248.084° W | 2026-09-18 07:29:05.575Z | 345.06° N | 82.48° | 2026-09-18 08:06:05.575Z | 69.305° E |
Co-orbital & Co-planar RSOs
Thresholds — Semi-major Axis: ±100 km, RAAN: ±3°, Inclination: ±5°
TCA is derived from TLE conjunctions
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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