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: 3 days ago
TLE from 3 days ago
0 ERS 1
1 21574U 91050A 26171.01462127 .00000124 00000-0 54570-4 0 9996
2 21574 98.7796 191.7818 0030737 258.2342 101.5397 14.39518368830452Epoch: 2026-06-20T00:21Z
TLE epoch observation values (Epoch: 2026-06-20T00:21:03.277Z)
Latitude
0.00004°
Longitude
-81.71718°
Altitude
767.484 km
Speed
7.468 km/s
True Right ascension
12h 47m 07s
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
00:28:32
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
779.158 km
Perigee altitude
735.294 km
Semi-major axis
7,135.363 km
Eccentricity
0.00307
Inclination
98.7796°
RAAN
191.7818°
Arg. of periapsis
258.2342°
True anomaly
101.88453°
Mean anomaly
101.5397°
Eccentric anomaly
101.71214°
Mean motion
3.60097 °/min
Orbital period
99.97 mins
BSTAR
0.00005457
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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. |
|---|---|---|---|---|---|---|---|
| 8 mins | 2026-06-22 14:39:01.906Z | 3.806° NNE | 2026-06-22 14:43:01.906Z | 290.659° WNW | 41° | 2026-06-22 14:47:01.906Z | 211.142° SW |
| 6 mins | 2026-06-23 00:15:01.906Z | 100.008° ESE | 2026-06-23 00:17:01.906Z | 71.747° E | 20.013° | 2026-06-23 00:21:01.906Z | 18.047° NNE |
| 7 mins | 2026-06-23 01:53:01.906Z | 198.116° SSW | 2026-06-23 01:56:01.906Z | 262.316° W | 35.675° | 2026-06-23 02:00:01.906Z | 329.911° NNW |
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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