EXPLORER 27, 1328
Orbit data source: Space-Track
EXPLORER 27, 1328 is a payload satellite owned by GSFC (US) in LEO that was launched on Thu, 29 Apr 1965 UTC via an SCOUT X-4 launch vehicle from the Wallops Island (WLPIS). 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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1328 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
APL
Mission
Civil Science
Bus & Motor
TRANSIT 5, Unknown motor
Mass
55 kg wet, 55 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Oct Cyl + 4 Pan + 4 Rod, 2.3 m
Radar Cross Section
2.996 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 10 hours ago
TLE from 10 hours ago
0 EXPLORER 27
1 01328U 65032A 25260.87769818 -.00000080 00000-0 39782-5 0 9992
2 01328 41.1833 102.4247 0244112 329.6968 28.9864 13.38897328951838Epoch: 2025-09-17T21:03Z
TLE epoch observation values (Epoch: 2025-09-17T21:03:53.122Z)
Latitude
-0.00004°
Longitude
149.40598°
Altitude
954.136 km
Speed
7.454 km/s
True Right ascension
06h 49m 41s
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
23:54:56
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,298.379 km
Perigee altitude
932.524 km
Semi-major axis
7,493.589 km
Eccentricity
0.02441
Inclination
41.1833°
RAAN
102.4247°
Arg. of periapsis
329.6968°
True anomaly
30.37898°
Mean anomaly
28.9864°
Eccentric anomaly
29.67893°
Mean motion
3.34586 °/min
Orbital period
107.6 mins
BSTAR
0.0000039782
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Other satellites on launch #32 in the year 1965 (1965-04-29 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.EXPLORER 27 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. |
|---|---|---|---|---|---|---|---|
| 8 mins | 2025-09-18 15:06:34.172Z | 173.788° S | 2025-09-18 15:10:34.172Z | 135.868° SSE | 16.633° | 2025-09-18 15:14:34.172Z | 99.485° ESE |
| 11 mins | 2025-09-18 16:58:34.172Z | 222.563° SW | 2025-09-18 17:03:34.172Z | 141.568° SSE | 39.387° | 2025-09-18 17:09:34.172Z | 78.967° E |
| 13 mins | 2025-09-18 18:51:34.172Z | 263.618° W | 2025-09-18 18:56:34.172Z | 295.192° NW | 44.654° | 2025-09-18 19:04:34.172Z | 81.595° E |
| 14 mins | 2025-09-18 20:44:34.172Z | 280.991° WNW | 2025-09-18 20:51:34.172Z | 102.655° ESE | 44.674° | 2025-09-18 20:58:34.172Z | 103.36° ESE |
| 14 mins | 2025-09-18 22:38:34.172Z | 278.735° WNW | 2025-09-18 22:44:34.172Z | 217.58° SW | 37.17° | 2025-09-18 22:52:34.172Z | 138.703° SSE |
| 7 mins | 2025-09-19 00:34:34.172Z | 251.37° W | 2025-09-19 00:37:34.172Z | 227.384° WSW | 15.828° | 2025-09-19 00:41:34.172Z | 195.805° SSW |
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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