Explorer 3

[[File:Explorer 3 Flight Recorder.jpg|thumb|upright=1.0|right|Explorer 3 Tape Recorder]]

[[File:Explorer 3 Flight Recorder.jpg|thumb|upright=1.0|right|Explorer 3 Tape Recorder]]

The objective of this spacecraft was a continuation of experiments started with Explorer 1. The [[Payload (air and space craft)|payload]] consisted of a [[micrometeorite]] detector (a wire grid array and acoustic detector) and the same [[cosmic ray]] counter (a [[Geiger-Müller tube]]) experiment included on Explorer 1, but this time with an on-board [[tape recorder]] to provide a complete [[radiation]] history for each orbit, Ludwig having had time to accommodate for the [[spin-stabilized satellite|spin-stabilization]] of the satellite.<Vanguard/>{{rp|241}}<ref name="Trajectory">{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/displayTrajectory.action?id=1958-003A|title=Trajectory: Explorer-3 1958-003A|publisher=NASA|date=14 May 2020|access-date=15 February 2021}} {{PD-notice}}</ref>

The objective of this spacecraft was a continuation of experiments started with Explorer 1. The [[Payload (air and space craft)|payload]] consisted of a [[micrometeorite]] detector (a wire grid array and acoustic detector) and the same [[cosmic ray]] counter (a [[Geiger-Müller tube]]) experiment included on Explorer 1, but this time with an on-board [[tape recorder]] to provide a complete [[radiation]] history for each orbit, Ludwig having had time to accommodate for the [[spin-stabilized satellite|spin-stabilization]] of the satellite.<ref name="Trajectory">{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/displayTrajectory.action?id=1958-003A|title=Trajectory: Explorer-3 1958-003A|publisher=NASA|date=14 May 2020|access-date=15 February 2021}} {{PD-notice}}</ref>

Its total weight was {{cvt|14.1|kg}}, of which {{cvt|8.4|kg}} was instrumentation. The instrument section at the front end of the satellite and the empty scaled-down [[MGM-29 Sergeant|fourth-stage rocket casing]] orbited as a single unit, to be spun around its long axis at 750 [[revolutions per minute]]. Data from these instruments would be transmitted to the ground by a 60 [[Watt|milliwatt]] transmitter operating on 108.03 [[hertz|MHz]] and a 10 milliwatt transmitter operating on 108.00 MHz.<ref name="Trajectory"/>

Its total weight was {{cvt|14.1|kg}}, of which {{cvt|8.4|kg}} was instrumentation. The instrument section at the front end of the satellite and the empty scaled-down [[MGM-29 Sergeant|fourth-stage rocket casing]] orbited as a single unit, to be spun around its long axis at 750 [[revolutions per minute]]. Data from these instruments would be transmitted to the ground by a 60 [[Watt|milliwatt]] transmitter operating on 108.03 [[hertz|MHz]] and a 10 milliwatt transmitter operating on 108.00 MHz.<ref name="Trajectory"/>