Mission record
Explorer 33
Also known as AIMP 1, Anchored IMP 1, IMP-D
NASA · Launched
Explore trajectoryCompleted · Partial success
NASA spin-stabilized IMP-D spacecraft planned to be the first U.S. spacecraft to go into lunar orbit; excess launch velocity left it in a highly elliptical Earth orbit, from which it measured the interplanetary magnetic and radiation environment until 1971.
- Destinations
- Launch vehicle
- Thor Delta E-1
- Launch site
- Cape Canaveral, Fla. / Launch Complex 17A
- Countries
- United States
- Mission types
- Orbiter, Heliophysics
Chronology
Mission timeline
Launch
Explorer 33 launched from Cape Kennedy, Florida
Original report time: 1966-07-01T16:02:25.500Z. Catalog timestamp identifies the containing second.
EarthDeployment
Four solar paddles deployed
Original report time: 1966-07-01T16:20:51.900Z. Catalog timestamp identifies the containing second.
EarthMilestone
Spacecraft separated from the Delta third stage
Original report time: 1966-07-01T16:21:21.900Z. Catalog timestamp identifies the containing second.
EarthMilestone
Retro motor burn ended
Original report time: 1966-07-01T22:33:13.200Z. Catalog timestamp identifies the containing second.
EarthMilestone
Engineers used an electronic "screwdriver" remotely to restore power to the blacked out bus
Earth
Mission architecture
Vehicles
Explorer 33 · Spacecraft
Destinations: Moon
Trajectory record
Time-dependent navigation trajectory
Source states place the model at the selected time. Reconstructed flight, estimates, predictions and historical mission plans are identified by interval; gaps remain visible.
Source records and sampling assumptions are retained with the repository data. Model attitude and surface appearance are illustrative.
- Explorer 33: SPDF source positions transformed to Sun-centered J2000; velocity derived from the position sequence. · July 1, 1966 to October 5, 1968
Provenance
Sources
Each source is listed once and labeled with the mission, event, trajectory, or destination/body context it supports.
Data verified through October 7, 2026
- AIMP technical summary and original engineering drawings — NASATechnical document · Supports: mission claims
- Explorer33 first interim flight report — NASATechnical document · Supports: mission claims · event claims
- Explorer 33 - NASA Science — NASAMission page · Supports: mission claims · event claims
- Explorer 33 restored GSFC magnetic and spacecraft ephemeris records — NASATechnical document · Supports: mission claims
- Explorer 33 - NASA NSSDCA Spacecraft Details — NSSDCAArchive · Supports: mission claims · event claims
- DE421 lunar mean-Earth and principal-axes frame specification — NAIFTechnical document · Supports: destination/body context
- DE440 lunar mean-Earth and principal-axes frame specification — NAIFSpice · Supports: destination/body context
- IAU rotational elements and body radii (PCK 00011) — NAIFSpice · Supports: destination/body context
- LOLA global lunar height maps, LDEM_4 V3 original PDS source label — NASATechnical document · Supports: destination/body context
- LOLA 2023 south-polar elevation, uncertainty and effective-resolution maps — NASATechnical document · Supports: destination/body context
- Blue Ghost Lunar Lander Seen From Above: LROC site and terrain context — NASATechnical document · Supports: destination/body context
- Moon Facts — NASAOther · Supports: destination/body context
- SLDEM2015 Blue Ghost region: original PDS elevation-grid label — NASATechnical document · Supports: destination/body context
- JPL Solar System Dynamics Astrodynamic Parameters — JPLOther · Supports: destination/body context
- Planet Sizes and Locations in Our Solar System — NASAOther · Supports: destination/body context