SL-6 R/B(2), 20666

Orbit data source: Space-Track

SL-6 R/B(2), 20666 is space debris in LEO originally from a launch on Thu, 21 Jun 1990 UTC launched from the Plesetsk Missile And Space Complex (PKMTR). Debris objects in space refer to the collection of defunct objects orbiting the Earth. Examples of debris include non-operational satellites, rocket bodies, and fragments generated from explosions, collisions, or faulty payload assembly.

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https://www.satcat.com/sats-embedded/20666?theme=dark&initialShowStats=false

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ISO8601 Format

Identifier

20666, 1990-055D

Orbit

LEO

Country

CIS

Related business

Russian Strategic Rocket Forces (RU)

Manufacturer

NPO Energiya

Mission

Spacecraft

Bus & Motor

BLOK-L, Unknown motor

Mass

900 kg wet, 900 kg dry

Launch date (UTC)

1990-06-21 (36 years ago)

Launch vehicle

Unknown

Launch site

Plesetsk Missile And Space Complex (PKMTR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Cyl, 1.6 m

Radar Cross Section

8.039 m², Large (>1 m²)

Expand to show TLE details & history
Last TLE update: 16 hours ago

TLE from 16 hours ago

0 SL-6 R/B(2)
1 20666U 90055D   26154.95114358  .00001890  00000-0  14882-3 0  9997
2 20666  62.7840 320.4153 0038509   3.3045 356.8301 15.03956034951161

Epoch: 2026-06-03T22:49Z

TLE epoch observation values (Epoch: 2026-06-03T22:49:38.805Z)

Latitude

-0.00003°

Longitude

85.6012°

Altitude

529.897 km

Speed

7.613 km/s

True Right ascension

21h 21m 39s

True Declination

0° 00' 00"

Sunlit

Object was in daylight at epoch

Visualization orbit readout

Latitude

Unknown

Longitude

Unknown

Altitude

Unknown

Speed

Unknown

Apparent Right ascension

Unknown

Apparent Declination

Unknown

Sunlit

N/A

Visualization observer readout

Local Sidereal Time

00:35:28

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

580.226 km

Perigee altitude

526.84 km

Semi-major axis

6,931.67 km

Eccentricity

0.00385

Inclination

62.784°

RAAN

320.4153°

Arg. of periapsis

3.3045°

True anomaly

356.80558°

Mean anomaly

356.8301°

Eccentric anomaly

356.81785°

Mean motion

3.76085 °/min

Orbital period

95.72 mins

BSTAR

0.00014882

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Other satellites on launch #55 in the year 1990 (1990-06-21 UTC)

COSMOS 2084, 20663

SL-6 R/B(1), 20664 (Decayed)

SL-6 DEB, 43502 (Decayed)

SL-6 PLAT, 20665 (Decayed)

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SL-6 R/B(2) 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.
4 mins	2026-06-04 20:04:43.590Z	8.436° NNE	2026-06-04 20:06:43.590Z	39.709° NE	15.155°	2026-06-04 20:08:43.590Z	71.005° E
6 mins	2026-06-04 21:43:43.590Z	314.265° NW	2026-06-04 21:45:43.590Z	253.802° W	42.791°	2026-06-04 21:49:43.590Z	155.712° SSE
4 mins	2026-06-05 11:40:43.590Z	143.248° SSE	2026-06-05 11:42:43.590Z	106.159° ESE	17.035°	2026-06-05 11:44:43.590Z	74.102° E
5 mins	2026-06-05 13:18:43.590Z	254.547° W	2026-06-05 13:20:43.590Z	309.662° NW	32.382°	2026-06-05 13:23:43.590Z	15.679° NNE

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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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Check out SL-6 R/B(2), 20666 on other resources

View SL-6 R/B(2), 20666 on Heavens-Above

View SL-6 R/B(2), 20666 on Keep Track

View SL-6 R/B(2), 20666 on Celestrak

View SL-6 R/B(2), 20666 on Gunter's Space Page

Satcat and Kayhan Space are not affiliated with NASA, Celestrak, Heavens-Above, Keep Track, or Gunter's Space Page.

SL-6 R/B(2), 20666

Orbit data source: Space-Track

Expand to show TLE details & historyLast TLE update: 16 hours ago

TLE from 16 hours ago

TLE epoch observation values (Epoch: 2026-06-03T22:49:38.805Z)

Visualization orbit readout

Visualization observer readout

Orbital elements

Other satellites on launch #55 in the year 1990 (1990-06-21 UTC)

SL-6 R/B(2) Visibility forecast

Co-orbital & Co-planar RSOs

Check out SL-6 R/B(2), 20666 on other resources

Documentation

Expand to show TLE details & history
Last TLE update: 16 hours ago