Re-entered 1989-03-03Debris

EXPLORER 11 DEB

NORAD: 3739
COSPAR: 1961-013B

OrbitalWiki publishes live orbits for active satellites only. This object is in the full catalogue: who launched it, what it is and its last published orbit are below, but there are no current orbital elements for it here.

Is it working?

Sources agree

Source	What it says	Date
CelesTrak SATCAT	Decayed or deorbited	1989-03-03
GCAT (J. McDowell)	Re-entered	1989-03-03

Each line is one source and what it says. Where they disagree, both are shown; OrbitalWiki does not pick a winner.

Spacecraft

Owner: NASA Goddard Space Flight Center
Mass at launch: 1 kg(estimate, good to about 20%)
Dry mass: 1 kg(estimate, good to about 20%)
Length: 0.1 m
Diameter: 0.4 m
Span with arrays and booms: 0.4 m
Shape: Disk

From GCAT by Jonathan McDowell (CC BY 4.0), record S03739, checked 2026-11-05. About this source

Launch

Launch date: 1961-04-27
Rocket: Juno II
Flight: Explorer 11
Mission name: NASA S-15
Launch site: CC, LC26B
Launched by: NASA Marshall Space Flight Center
Rocket performance: Success
Launch designator: 1961 NU

From the GCAT launch log, launch 1961 NU, checked 2026-11-05. About this source

Catalogue record

Object type: Debris
Owner code: US
Launch date: 1961-04-27
Re-entered: 1989-03-03
Period: 89.8 min
Inclination: 28.80°
Apogee: 285 km
Perigee: 242 km
Radar cross-section: 0.1575 m²

From CelesTrak SATCAT, checked 2026-11-05. About this source

Where it came from

Parent object: EXPLORER 11 (NORAD 107)

The object this one was attached to at launch, or broke off from, as GCAT records it.