CALSPHERE 4(A), 1520
Orbit data source: Space-Track
CALSPHERE 4(A), 1520 is a payload satellite owned by NRL (US) in LEO that was launched on Fri, 13 Aug 1965 UTC via a THOR ABLESTAR launch vehicle from the Air Force Western Test Range (AFWTR). 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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1520 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
NRL
Mission
Operational Defense Calibration
Bus & Motor
NRL 14", Unknown motor
Mass
4 kg wet, 4 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Sphere, 0.2 m
Radar Cross Section
0.126 m², Small (<0.1 m²)
Expand to show TLE details & historyLast TLE update: 6 hours ago
TLE from 6 hours ago
0 CALSPHERE 4(A)
1 01520U 65065H 25242.90305752 .00000107 00000-0 18915-3 0 9991
2 01520 89.9177 125.1386 0068385 201.6415 169.9658 13.36212220923949Epoch: 2025-08-30T21:40Z
TLE epoch observation values (Epoch: 2025-08-30T21:40:24.169Z)
Latitude
11.69762°
Longitude
-179.27583°
Altitude
1,176.136 km
Speed
7.242 km/s
True Right ascension
08h 20m 37s
True Declination
11° 37' 60"
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
19:02:05
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,171.771 km
Perigee altitude
1,069.213 km
Semi-major axis
7,498.629 km
Eccentricity
0.00684
Inclination
89.9177°
RAAN
125.1386°
Arg. of periapsis
201.6415°
True anomaly
170.1012°
Mean anomaly
169.9658°
Eccentric anomaly
170.03361°
Mean motion
3.34249 °/min
Orbital period
107.7 mins
BSTAR
0.00018915
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Other satellites on launch #65 in the year 1965 (1965-08-13 UTC)
CALSPHERE 4(A) Visibility forecast
Observer location: undefined°, undefined°
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. |
|---|---|---|---|---|---|---|---|
| 11 mins | 2025-08-31 03:37:17.777Z | 25.17° NE | 2025-08-31 03:42:17.777Z | 80.361° E | 28.294° | 2025-08-31 03:48:17.777Z | 144.953° SSE |
| 10 mins | 2025-08-31 05:25:17.777Z | 341.252° N | 2025-08-31 05:30:17.777Z | 276.281° WNW | 32.705° | 2025-08-31 05:35:17.777Z | 218.193° SW |
| 11 mins | 2025-08-31 15:42:17.777Z | 138.623° SSE | 2025-08-31 15:47:17.777Z | 85.211° E | 31.594° | 2025-08-31 15:53:17.777Z | 16.75° NNE |
| 11 mins | 2025-08-31 17:30:17.777Z | 217.18° SW | 2025-08-31 17:35:17.777Z | 277.92° WNW | 31.302° | 2025-08-31 17:41:17.777Z | 340.339° N |
| 6 mins | 2025-09-01 03:01:17.777Z | 50.639° ENE | 2025-09-01 03:04:17.777Z | 81.551° E | 16.806° | 2025-09-01 03:07:17.777Z | 110.778° ESE |
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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Authenticating...
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