DELTA 1 DEB, 21551

Orbit data source: Space-Track

DELTA 1 DEB, 21551 is space debris in SSO originally from a launch on Thu, 12 Jun 1975 UTC launched from the Air Force Western Test Range (AFWTR). 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.

Loading next visibility...

Iframe embed code

<iframe src="https://www.satcat.com/sats-embedded/21551?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/21551?theme=dark&initialShowStats=false

Optional Secondary NORAD IDs

Max 10 NORAD IDs; Separated by commas

Initial load time (optional)

ISO8601 Format

TLE date request (optional)

ISO8601 Format

Identifier

21551, 1975-052HF

Orbit

SSO

Country

Related business

National Aeronautics and Space Administration (NASA) (US)

Manufacturer

Unknown

Mission

Spacecraft

Bus & Motor

Unknown

Mass

Unknown

Launch date (UTC)

1975-06-12 (51 years ago)

Launch vehicle

Unknown

Launch site

Air Force Western Test Range (AFWTR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Unknown shape, 0.1 m

Radar Cross Section

Medium (>0.1 m² and <1 m²)

Expand to show TLE details & history
Last TLE update: 1 day ago

TLE from 1 day ago

0 DELTA 1 DEB
1 21551U 75052HF  26181.62907373  .00000027  00000-0  15580-3 0  9999
2 21551  99.7818  75.4812 0104993 280.9520 106.8260 13.24628999696408

Epoch: 2026-06-30T15:05Z

TLE epoch observation values (Epoch: 2026-06-30T15:05:51.970Z)

Latitude

28.50942°

Longitude

-75.02876°

Altitude

1,194.164 km

Speed

7.248 km/s

True Right ascension

04h 40m 32s

True Declination

28° 22' 25"

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

13:40:04

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

1,243.621 km

Perigee altitude

1,085.238 km

Semi-major axis

7,542.567 km

Eccentricity

0.0105

Inclination

99.7818°

RAAN

75.4812°

Arg. of periapsis

280.952°

True anomaly

107.97319°

Mean anomaly

106.826°

Eccentric anomaly

107.40004°

Mean motion

3.31333 °/min

Orbital period

108.65 mins

BSTAR

0.0001558

Loading maneuver chart data...

Computing Atmospheric mass density...

Loading historical data...

Other satellites on launch #52 in the year 1975 (1975-06-12 UTC)

DELTA 1 DEB, 21597 (Decayed)

DELTA 1 DEB, 42655

DELTA 1 DEB, 21343 (Decayed)

DELTA 1 DEB, 21562 (Decayed)

Did you know?

You can import UDL-sourced sensor .json files into the Sandbox to generate a visibility chart that accounts for multi-vendor sensor geometry.

Click here to try in Sandbox

DELTA 1 DEB Visibility forecast

Loading observer location...
Set Observer location

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.
13 mins	2026-07-02 05:38:01.462Z	20.745° NNE	2026-07-02 05:44:01.462Z	98.219° ESE	43.465°	2026-07-02 05:51:01.462Z	187.167° SSW
9 mins	2026-07-02 07:26:01.462Z	344.249° N	2026-07-02 07:30:01.462Z	306.918° NW	21.782°	2026-07-02 07:35:01.462Z	257.798° W
11 mins	2026-07-02 16:02:01.462Z	128.862° SE	2026-07-02 16:07:01.462Z	65.863° ENE	35.082°	2026-07-02 16:13:01.462Z	359.869° N
11 mins	2026-07-02 17:49:01.462Z	205.695° SW	2026-07-02 17:54:01.462Z	261.496° W	29.967°	2026-07-02 18:00:01.462Z	324.907° NNW

Items per page:

1–4 of 4 items

of 1 page

Co-orbital & Co-planar RSOs

Thresholds — Semi-major Axis: ±100 km, RAAN: ±3°, Inclination: ±5°
TCA is derived from TLE conjunctions

Please sign-in to view Co-orbital & Co-planar RSOs.

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

CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings

Authenticating...

Click to sort rows by Secondary header in ascending order	Click to sort rows by Secondary name header in ascending order	Click to sort rows by Country header in ascending order	Click to sort rows by Owner header in ascending order	Click to sort rows by Obj. Type header in ascending order	Click to sort rows by Miss dist. header in ascending order	Click to sort rows by Rel. speed header in ascending order	Click to sort rows by Apr. angle header in ascending order	Click to sort rows by TCA header in descending order

Check out DELTA 1 DEB, 21551 on other resources

View DELTA 1 DEB, 21551 on Heavens-Above

View DELTA 1 DEB, 21551 on Keep Track

View DELTA 1 DEB, 21551 on Celestrak

View DELTA 1 DEB, 21551 on Gunter's Space Page

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

DELTA 1 DEB, 21551

Orbit data source: Space-Track

Expand to show TLE details & historyLast TLE update: 1 day ago

TLE from 1 day ago

TLE epoch observation values (Epoch: 2026-06-30T15:05:51.970Z)

Visualization orbit readout

Visualization observer readout

Orbital elements

Other satellites on launch #52 in the year 1975 (1975-06-12 UTC)

DELTA 1 DEB Visibility forecast

Co-orbital & Co-planar RSOs

Check out DELTA 1 DEB, 21551 on other resources

Documentation

Expand to show TLE details & history
Last TLE update: 1 day ago