Showing default

EXPLORER 20, 870

Orbit data source: Space-Track

EXPLORER 20, 870 is a payload satellite owned by GSFC (US) in LEO that was launched on Tue, 25 Aug 1964 UTC via an SCOUT X-4 launch vehicle from the Air Force Western Test Range (AFWTR). 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.

Loading next visibility...

Iframe embed code

<iframe src="https://www.satcat.com/sats-embedded/870?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/870?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

870, 1964-051A

Orbit

LEO

Last TLE update

13 hours ago

Origin

National Aeronautics and Space Administration (NASA) (US)

Manufacturer

Cutler-Hammer/AIL

Mission

Civil Science

Bus & Motor

S-48, Unknown motor

Mass

44 kg wet, 44 kg dry

Launch date (UTC)

1964-08-25 (61 years ago)

Launch vehicle

SCOUT X-4

Launch site

Air Force Western Test Range (AFWTR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Double Cone + 6 Rod, 37 m

Radar Cross Section

0.292 m², Medium (>0.1 m² and < 1m²)

Expand to show TLE details & history

TLE from 13 hours ago

0 EXPLORER 20
1 00870U 64051A   25128.71441389  .00000146  00000-0  10580-3 0  9994
2 00870  79.8997 358.8824 0096465 266.8453  92.1663 13.91681666 77174

Epoch: 2025-05-08T17:08Z

Definitive object data (Epoch: 2025-05-08T17:08:45.36Z)

Latitude

0.00004°

Longitude

-125.08754°

Altitude

928.913 km

Speed

7.386 km/s

True Right ascension

23h 55m 31s

True Declination

0° 00' 00"

Sunlit

Object was in daylight at TLE epoch

Visualization TLE readout

Latitude

-31.54173°

Longitude

60.56275°

Altitude

892.205 km

Speed

7.426 km/s

Apparent Right ascension

08h 51m 34s

Apparent Declination

-67° 29' 45"

Sunlit

Object is in full shadow

Visualization observer readout

Local Sidereal Time

14:23:42

Azimuth

207.228° SW

Elevation

-33.862°

Doppler factor

Orbital elements

Apogee altitude

990.412 km

Perigee altitude

849.609 km

Semi-major axis

7,298.147 km

Eccentricity

0.0096465

Inclination

79.8997°

RAAN

358.8824°

Arg. of periapsis

266.8453°

True anomaly

93.27035°

Mean anomaly

92.1663°

Eccentric anomaly

92.71838°

Mean motion

3.48116 °/min

BSTAR

0.0001058

Orbital period

103.41 mins

Loading maneuver chart data...

Loading SW <> Apogee altitude chart data...

Loading historical data...

Other satellites on launch #51 in the year 1964 (1964-08-25 UTC)

SCOUT X-4 R/B, 871

SCOUT X-4 DEB, 873 (Decayed)

SCOUT X-4 DEB, 874 (Decayed)

SCOUT X-4 DEB, 875 (Decayed)

SCOUT X-4 DEB, 40592 (Decayed)

EXPLORER 20 Visibility forecast

Observer location: undefined°, undefined°

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.
11 mins	2025-05-09 15:40:53.886Z	168.131° S	2025-05-09 15:45:53.886Z	103.834° ESE	38.55°	2025-05-09 15:51:53.886Z	21.456° NNE
8 mins	2025-05-09 17:27:53.886Z	253.944° W	2025-05-09 17:30:53.886Z	290.004° WNW	21.736°	2025-05-09 17:35:53.886Z	344.154° N
10 mins	2025-05-10 02:31:53.886Z	4.041° NNE	2025-05-10 02:35:53.886Z	69.681° E	39.471°	2025-05-10 02:41:53.886Z	152.772° SSE
7 mins	2025-05-10 04:16:53.886Z	309.939° NW	2025-05-10 04:19:53.886Z	276.225° WNW	19.672°	2025-05-10 04:23:53.886Z	231.239° WSW

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 ascending order

Check out EXPLORER 20, 870 on other resources

View EXPLORER 20, 870 on NASA - NSSDCA Website

View EXPLORER 20, 870 on Heavens-Above

View EXPLORER 20, 870 on Keep Track

View EXPLORER 20, 870 on Celestrak

View EXPLORER 20, 870 on Gunter's Space Page

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