ERS 1, 21574
Orbit data source: Space-Track
ERS 1, 21574 is a payload satellite owned by ESA (ESA) in SSO that was launched on Wed, 17 Jul 1991 UTC via an ARIANE 40 launch vehicle from the French Guiana (FRGUI). 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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21574 intel report (Beta)
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Identifier
Orbit
Country
ESARelated business
Manufacturer
DASA-F
Mission
Non-operational Civil Sci/Misc
Bus & Motor
ESA ERS, ERS AOCS
Mass
2,384 kg wet, 2,080 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Box + 1 Pan, 5.9 m
Radar Cross Section
15.593 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 16 hours ago
TLE from 16 hours ago
0 ERS 1
1 21574U 91050A 26284.30939874 .00000287 00000-0 10623-3 0 9991
2 21574 98.7750 307.8246 0030824 282.7956 76.9787 14.39577301846757Epoch: 2026-10-11T07:25Z
TLE epoch observation values (Epoch: 2026-10-11T07:25:32.051Z)
Latitude
-0.00003°
Longitude
176.53704°
Altitude
757.941 km
Speed
7.478 km/s
True Right ascension
20h 31m 17s
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
18:04:28
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
779.024 km
Perigee altitude
735.038 km
Semi-major axis
7,135.168 km
Eccentricity
0.00308
Inclination
98.775°
RAAN
307.8246°
Arg. of periapsis
282.7956°
True anomaly
77.32313°
Mean anomaly
76.9787°
Eccentric anomaly
77.15089°
Mean motion
3.60111 °/min
Orbital period
99.97 mins
BSTAR
0.00010623
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Other satellites on launch #50 in the year 1991 (1991-07-17 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.ERS 1 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. |
|---|---|---|---|---|---|---|---|
| 5 mins | 2026-10-12 00:16:39.428Z | 93.68° ESE | 2026-10-12 00:19:39.428Z | 55.845° ENE | 15.644° | 2026-10-12 00:21:39.428Z | 31.256° NE |
| 8 mins | 2026-10-12 01:53:39.428Z | 178.414° S | 2026-10-12 01:57:39.428Z | 268.369° W | 65.216° | 2026-10-12 02:01:39.428Z | 338.305° N |
| 8 mins | 2026-10-12 14:02:39.428Z | 34.195° NE | 2026-10-12 14:06:39.428Z | 106.225° ESE | 40.813° | 2026-10-12 14:10:39.428Z | 166.275° S |
| 6 mins | 2026-10-12 15:42:39.428Z | 331.024° NNW | 2026-10-12 15:44:39.428Z | 300.682° NW | 23.729° | 2026-10-12 15:48:39.428Z | 245.516° WSW |
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 descending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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