Explorer 1
Explorer 1 was the first satellite successfully launched by the United States. Built by the Jet Propulsion Laboratory with a cosmic-ray experiment led by James Van Allen, the compact spacecraft measured energetic particles, temperatures, and micrometeorite effects during the International Geophysical Year.
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Identity
- Aliases
- Explorer ISatellite 1958 Alpha1958-001A
- Name
- Explorer 1
- Status
- completed
Details
- Astronauts
- -
- Description
- Explorer 1 was the first satellite successfully launched by the United States. Built by the Jet Propulsion Laboratory with a cosmic-ray experiment led by James Van Allen, the compact spacecraft measured energetic particles, temperatures, and micrometeorite effects during the International Geophysical Year.
- Destination
- Elliptical Earth orbit at approximately 360 km perigee and 2,535 km apogee (33.3° inclination; 114.8-minute period)
- End Date
- 1958-05-23
- Launch Site
- Outcome
- Explorer 1 entered Earth orbit and transmitted through May 23, 1958. Periods of unexpectedly low detector counts helped reveal that the instrument was saturating in intense trapped radiation; Explorer 3 data confirmed the belts around Earth that became known as the Van Allen belts.
- Programs
- Start Date
- 1958-01-31
- Vehicle Families
Links
- Official Url
- https://science.nasa.gov/mission/explorer-1/
Assets & Meta
- Creation Time
- July 18, 2026 at 18:38:04 UTC
- Updated Time
- August 21, 2026 at 17:56:06 UTC
- Image
- Download
Other
- Affiliations
- Search Name
- Explorer 1 Explorer I Satellite 1958 Alpha 1958-001A
- Space Stations
- -
- Vehicles