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ESSA 2 (OT-2), 2091

Orbit data source: Space-Track

ESSA 2 (OT-2), 2091 is a payload satellite owned by ESSA (US) in SSO that was launched on Mon, 28 Feb 1966 UTC via a THOR DELTA E launch vehicle from the Air Force Eastern Test Range (AFETR). 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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<iframe src="https://www.satcat.com/sats-embedded/2091?theme=dark&initialShowStats=false" width="600" height="400" frameborder="0" title="Kayhan Space Satcat Satellite Viewer"></iframe>

Iframe URL

https://www.satcat.com/sats-embedded/2091?theme=dark&initialShowStats=false

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ISO8601 Format

Identifier

2091, 1966-016A

Orbit

SSO

Country

Related business

National Oceanic and Atmospheric Administration (US)

Manufacturer

RCA/East Windsor

Mission

Non-operational spacecraft

Bus & Motor

TIROS I, Unknown motor

Mass

130 kg wet, 130 kg dry

Launch date (UTC)

1966-02-28 (60 years ago)

Launch vehicle

THOR DELTA E

Launch site

Air Force Eastern Test Range (AFETR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Unknown

Radar Cross Section

Medium (>0.1 m² and <1 m²)

Expand to show TLE details & history
Last TLE update: 12 hours ago

TLE from 12 hours ago

0 ESSA 2 (OT-2)
1  2091U 66016A   25318.52386330 -.00000027  00000-0  88694-4 0  9999
2  2091 101.2376 228.0020 0038789 332.7656 200.6300 12.69426483766381

Epoch: 2025-11-14T12:34Z

TLE epoch observation values (Epoch: 2025-11-14T12:34:21.789Z)

Latitude

6.56149°

Longitude

166.84815°

Altitude

1,414.484 km

Speed

7.141 km/s

True Right ascension

03h 17m 13s

True Declination

6° 31' 33"

Sunlit

Object was in full shadow 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

20:45:45

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

1,411.869 km

Perigee altitude

1,351.669 km

Semi-major axis

7,759.906 km

Eccentricity

0.00388

Inclination

101.2376°

RAAN

228.002°

Arg. of periapsis

332.7656°

True anomaly

200.4741°

Mean anomaly

200.63°

Eccentric anomaly

200.55198°

Mean motion

3.17511 °/min

Orbital period

113.38 mins

BSTAR

0.000088694

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Other satellites on launch #16 in the year 1966 (1966-02-28 UTC)

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ESSA 2 (OT-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.
9 mins	2025-11-15 05:21:52.325Z	57.102° ENE	2025-11-15 05:25:52.325Z	89.545° E	17.322°	2025-11-15 05:30:52.325Z	129.307° SE
14 mins	2025-11-15 07:11:52.325Z	15.795° NNE	2025-11-15 07:17:52.325Z	357.385° N	44.646°	2025-11-15 07:25:52.325Z	200.861° SSW
9 mins	2025-11-15 09:04:52.325Z	340.028° N	2025-11-15 09:08:52.325Z	305.815° NW	18.801°	2025-11-15 09:13:52.325Z	266.558° W
10 mins	2025-11-15 16:12:52.325Z	95.522° ESE	2025-11-15 16:17:52.325Z	50.732° ENE	21.306°	2025-11-15 16:22:52.325Z	9.625° NNE
14 mins	2025-11-15 18:01:52.325Z	167.347° S	2025-11-15 18:07:52.325Z	232.092° WSW	44.524°	2025-11-15 18:15:52.325Z	341.202° N
5 mins	2025-11-15 19:58:52.325Z	256.77° W	2025-11-15 20:00:52.325Z	272.97° WNW	13.326°	2025-11-15 20:03:52.325Z	296.215° NW

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 ESSA 2 (OT-2), 2091 on other resources

View ESSA 2 (OT-2), 2091 on NASA - NSSDCA Website

View ESSA 2 (OT-2), 2091 on Heavens-Above

View ESSA 2 (OT-2), 2091 on Keep Track

View ESSA 2 (OT-2), 2091 on Celestrak

View ESSA 2 (OT-2), 2091 on Gunter's Space Page

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

ESSA 2 (OT-2), 2091

Orbit data source: Space-Track

Expand to show TLE details & historyLast TLE update: 12 hours ago

TLE from 12 hours ago

TLE epoch observation values (Epoch: 2025-11-14T12:34:21.789Z)

Visualization orbit readout

Visualization observer readout

Orbital elements

Other satellites on launch #16 in the year 1966 (1966-02-28 UTC)

ESSA 2 (OT-2) Visibility forecast

Co-orbital & Co-planar RSOs

Check out ESSA 2 (OT-2), 2091 on other resources

Documentation

Expand to show TLE details & history
Last TLE update: 12 hours ago