Pioneer P-3

Pioneer P-3
Image of a Pioneer P probe
Mission goal	Images of the lunar surface
Client	NASA
Launcher	Atlas Able
Course of the mission
Start date	November 26, 1959, 07:26 UTC
launch pad	CCAFS , LC-14
End date	November 26, 1959
11/28/1959 begin 11/28/1959 Loss of the probe due to failure of the payload fairing

Pioneer P-3 was another failed attempt by the US space agency NASA to launch a lunar satellite as part of the Pioneer program . The spacecraft should swing into a high orbit around the moon and take pictures of the surface and carry out further experiments. Just 45 seconds after takeoff, the payload fairing came off , resulting in an unstable trajectory for the rocket and ultimately total loss. In order to conceal the numerous failures, NASA decided not to assign a proper mission number and named the device "P-3". The same procedure was followed with the attempt “P-1” and with the subsequent failed space probes “P-30” and “P-31”.

The Atlas-D-Able - Pioneer P-3 launcher before takeoff

construction

Pioneer P-3 had a spherical shape with a diameter of 1 meter. After extending the solar panels , it would have had a span of 2.7 meters. The probe contained several measuring instruments, including a micrometeorite detector , a Geiger-Müller counter tube , a proportional counter , a sun detector and an ionization chamber . 52 small propeller blades should contribute to the thermal regulation of Pioneer P-3. If the temperature of the probe was too cool, these would have opened in order to raise the temperature of the probe through sunlight. If the temperature was too high, they would have closed again.

Mission history

The space probe was supposed to be launched in early October with an Atlas 9C launcher, but the vehicle exploded on September 24 during a static test on the launch pad. Fortunately, the probe was not attached yet. This inevitably aborted attempt was given the name "Pioneer P-1". In order to start the device anyway, a surplus Atlas-D reserve package from the Mercury program was used .

It was planned that the probe should be decelerated by brake rockets after reaching the moon in order to enter a lunar orbit. Because of the destruction of the probe on launch, the mission was a total failure.

Web links and sources

Commons : Pioneer (space probe program)  - collection of images, videos and audio files

• Pioneer P-3 on Nasa.gov (English)
• Pioneer P-3 in the Encyclopedia Astronautica (English)
• Bernd Leitenberger: The Atlas Able (Pioneer P) space probes
• The Space Review: The Pioneer lunar orbiters: a forgotten failure (English)