PI/Engineer: D. L. Reasoner, Rice University
Other Contacts: Brian J. O'Brien, Univ. of Sydney
Apollo Flight Nos.: 14
Apollo Exp't No. S 038
Discipline: solar wind - charged particles radiation
Weight: 2.5 kg
Dimensions: 28.7 x 21.6 x 11.4 cm, stowed 46 cm high, deployed
Manufacturer: Bendix
Description/Purpose:
This experiment was designed to measure the ambient fluxes of charged particles, both electrons and ions, with energies in the range of 50 to 50,000 eV. One of the most stable features observed was the presence of low-energy electrons whenever the site is illuminated by the Sun. The variation during the lunar eclipse provided strong evidence that these were photo-electrons liberated from the lunar surface.
The CPLEE consists of a box supported by legs. It contains 2 similar physical charged-particle analyzers oriented in different directions for minimum exposure to the ecliptic path of the sun. Each detector package had six particle detectors (five provided information about particle energy distribution, and the sixth provided high sensitivity at low particle fluxes), 2 different programmable high-voltage power supplies, and other circuitry.
Unloading from the LM: As part of ALSEP
Transporting by foot or MET: As part of ALSEP
Loading/unloading tools/exp'ts on LRV: NA
Site selection: As part of ALSEP
Deploying experiment:
Accomplished without difficulty. Alignment and leveling were within 2deg and 2.5deg, respectively, by using a Sun compass and bubble level. Timeline shows ~5 minutes allotted for deploying the unit.
Check-out of experiment:
Calibration was enabled by a 63Ni radioactive source placed on the underside of the dust cover, which was not removed until after LM ascent. More extensive calibration occurred on Earth before launch.
Operation of experiment:
From JSC via the ALSEP command system. The dust cover was not removed until after LM ascent. A brief functional test of 5 minutes duration was done during the 1st EVA.
Repairs to experiment: None required.
Recovery/take-down of experiment: NA
Stowing experiment for return: NA
Loading/unloading samples on LRV: NA
Loading of exp't/samples into the LM: NA
Stowing of package once in the LM: NA
Sampling operations - soil, rocks: NA
Trenching: NA
Raking: NA
Drilling: NA
Navigating/recognizing landmarks: NA
Were there any hazards in the experiment?
i.e. hazardous materials (explosive, radioactive, toxic), sharp objects, high voltages, massive, bulky, tripping hazards, temperatures?
High voltages were not turned on until the unit was activated by Earth command. A 63Ni radioactive source was placed on the underside of the dust cover for calibration, but its dose was not high enough to be a major concern.
Was lighting a problem? No.
Were the results visible to the crew? Just alignment and level.
Would you recommend any design changes? No comments by crew.
Were any special tools required?
UHT for deployment and alignment.
Was the orientation of the experiment (i.e. horizontal/vertical) important? Difficult?
It had to be level within 2.5deg and aligned within 2deg of the E-W sun line. It was aligned using the shadow of the UHT while in the carrying socket and alignment marks on the experiment.
Was the experiment successful? Yes
Were there related experiments on other flights? See SIDE (S036).
Where was it stored during flight? As part of ALSEP
Were there any problems photographing the experiment? No
What pre-launch and cruise req'ts were there?
power, thermal, late access, early recovery?
What was different between training and actual EVA? No comments by crew.
What problems were due to the suit rather than the experiment? No comments by crew.
Any experiences inside the LM of interest from the experiment/operations viewpoint?
No comments by crew.
References:
A-14 Preliminary Science Report
Apollo Scientific Experiments Data Handbook, JSC-09166, NASA TM X-58131, August, 1974, In JSC History Office.
Apollo 14 Final Lunar Surface Procedures, JCS, December 31, 1970
Apollo Program Summary Report, section 3.2.20 Charged-Particle Lunar Environment Experiment, JCS-09423, April, 1975.
ALSEP Termination Report, NASA Reference Publication 1036, April, 1979.