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Explorer I (00004)
COSPAR: 1958-001A | Alt Name: EXPLORER 1
DECAYED
Image
Additional Sources
Launch Details
Launch Date
February 1, 1958
Launch Site
Launch Pad
LC-26A
Launch Vehicle
Orbital Elements
NORAD ID
00004
International Designator
1958-001A
Decay Date
3/31/1970
Basic Satellite Info
Name
Explorer I
Alternative Name
EXPLORER 1
Type
Payload
Status
Decayed
Country
United States
Constellation
N/A
Related Satellites
Major Events
First U.S. satellite, discovered Van Allen radiation belts
Summary
Explorer 1 is a satellite launched on February 1, 1958, by the US with a mass of 8 kg and dimensions of 0.8 meters in length and 0.1 meters in diameter. The satellite was manufactured by JPLA and owned by ABMA/JPLA.
The Explorer 1 mission details are not provided, but it is known to have been launched from the AFETR launch site on a Jupiter C rocket. After its stable date of February 1, 1958, the satellite's status changed to Decayed.
Physical Characteristics
Length
2.03
Diameter
0.152
Span
0.152
Dry Mass
13.97
Launch Mass
8
Shape
Cyl
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Sandblasted stainless steel with white stripes
Material Composition
Stainless steel, fiberglass
Technical Details
Payload
Cosmic ray detector, temperature sensors, micrometeorite detectors
Purpose
Scientific research
Mission
Cosmic ray and micrometeorite research
Manufacturer
Jet Propulsion Laboratory
Life Expectancy
Operated until May 23, 1958. Reentered atmosphere on March 31, 1970
Bus
Jupiter-C
Configuration
Cylindrical with whip antennas
Motor
N/A
Equipment
Cosmic ray detector, temperature sensors, micrometeorite detectors, two transmitters
Power System
Mercury chemical batteries
ADCS
Spin-stabilized
Transmitter Frequency
108.00 MHz, 108.03 MHz
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