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Explorer III (00006)
COSPAR: N/A | Alt Name: EXPLORER 3
DECAYED
Image
Additional Sources
Launch Details
Launch Date
March 26, 1958
Launch Site
Launch Pad
LC-5
Launch Vehicle
Orbital Elements
NORAD ID
00006
International Designator
N/A
Decay Date
6/28/1958
Basic Satellite Info
Name
Explorer III
Alternative Name
EXPLORER 3
Type
Payload
Status
Decayed
Owner
U.S. Army Ballistic Missile Agency/Jet Propulsion Laboratory
Country
United States
Constellation
N/A
Related Satellites
Major Events
Launched on March 26, 1958; Discovered to be in a tumbling motion with a period of about 7 seconds; Decayed from orbit on June 28, 1958
Summary
Explorer 3 is a satellite launched on March 26, 1958, from AFETR's Launch Site LC5 using a Jupiter C launch vehicle. It has a length of approximately 0.8 meters and a dry mass of about 8 kilograms.
The satellite was manufactured by JPLA (Jet Propulsion Laboratory) for ABMA/JPLA, with its mission not specified in available information. Explorer 3 is now in a decayed state, denoted as "D" in the NORAD catalog.
Physical Characteristics
Length
2.03
Diameter
0.152
Span
0.152
Dry Mass
8.4
Launch Mass
14.1
Shape
Cyl
Radar Cross Section
0.15
Visual Magnitude
6
Color
White and dark green alternating strips
Material Composition
Aluminum alloy
Technical Details
Payload
Explorer 3
Purpose
Scientific research
Mission
Continuation of experiments started with Explorer 1, study of cosmic rays and micrometeorites
Manufacturer
Jet Propulsion Laboratory
Life Expectancy
Decayed from orbit on June 28, 1958, after 93 days of operation
Bus
Explorer 1
Configuration
Cylindrical with nosecone
Motor
Sergeant solid-fuel rocket motor
Equipment
Cosmic ray counter (Geiger-Mueller tube), micrometeorite detector (erosion gauge), on-board tape recorder, low power transmitter (10 mW, 108.00 MHz), high power transmitter (60 mW, 108.03 MHz), command receiver
Power System
60 Watts; Mallory mercury batteries
ADCS
Spin-stabilized, nominal spin rate of 20 rpm
Transmitter Frequency
108.00 MHz, 108.03 MHz
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