Experiment Operations During Apollo EVAs

Experiment: Thermal Degradation Sample

Acronym: TDS


Panels 1 to 6 of TDS 1002 covered with soil (AS14-77-10362). This photo was taken with the Apollo Lunar Closeup Camera.

PI/Engineer: unknown
Other Contacts:

Apollo Flight Nos.: 14
Apollo Exp't No.:

Discipline: Materials of Construction

Weight: 180 g each array, x 2
Dimensions:

Manufacturer: probably JSC

Description/Purpose:
To evaluate the effect of lunar dust on the optical properties (absorptivity and emissivity) of 12 candidate thermal coatings. Two duplicate arrays each containing samples of the 12 coatings, were taken to the Moon. After covering them with dust, one was tapped to remove the dust and the other was cleaned with a nylon-bristle brush.

Unloading from the LM: It was stowed inside the LM in the interim stowage assembly in front of the center instrument panel. It was brought to the surface in an equipment transfer bag.

Transporting by foot or MET:
Carried on the MET to the first geological station.

Loading/unloading tools/exp'ts on LRV: NA

Site selection:
Performed at the first geological station while the LMP performed the LPM experiment.

Deploying experiment: On the SRC table of the MET.

Check-out of experiment: NA

Operation of experiment:
The CDR opened one array and placed it on the sample return container table on the MET. He photographed it with the Apollo Lunar Closeup stereoscopic Camera (ALCC). He then scooped up some lunar material with the small scoop and placed it on the array. He then shook off the dust and took more pictures. He then brushed the array with a nylon brush and again took photos. He folded and stowed this array. After taking out the 2nd TDS, he put soil on this array and again tapped it clean, and photographed it. It was not brushed clean. A series of seven stereopairs of the arrays were obtained (using the ALCC) for 3 conditions: when the arrays were pristine, when the arrays were dusted with lunar soil, and after the lunar dust had been brushed or tapped off. The arrays were then packaged in a closed, but not vacuum sealed, container (the hand tool carrier pouch) and returned to Earth. Shepard commented that he was surprised by the low adherence of the dust to the array.

Repairs to experiment: None required.

Recovery/take-down of experiment:
Once brushed off or tapped clean, they were folded and packaged for return to Earth for extensive evaluation of their thermal properties.

Stowing experiment for return: Placed in its bag.

Loading/unloading samples on LRV: NA

Loading of exp't/samples into the LM: No comments by crew.

Stowing of package once in the LM:
Stowed in its bag in the interim stowage assembly over the ascent stage engine cover.

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?: No.

Was lighting a problem?: NA

Were the results visible to the crew?: Yes.

Would you recommend any design changes?: No.

Were any special tools required?:
Lunar Surface Closeup Stereoscopic Camera, nylon-bristle brush, sampling scoop.

Was the orientation of the experiment (i.e. horizontal/vertical) important? Difficult?: No.

Was the experiment successful?: Yes.

Were there related experiments on other flights?:
A-12 sampled parts of the Surveyor 3 spacecraft after 31 months of exposure. LDEF was left in Earth orbit for ~6 years to determine materials' ability to withstand the LEO environment.

Where was it stored during flight?: Uncertain

Were there any problems photographing the experiment?: No.

What pre-launch and cruise req'ts were there? power, thermal, late access, early recovery?:
None

What was different between training and actual EVA?: No comments by crew.

What problems were due to the suit rather than the experiment?:
The astronauts could have picked up a static charge while on EVA and transferred this charge to the test articles. This charge would have attracted the dust. It is unknown if this was a factor.

Any experiences inside the LM of interest from the experiment/operations viewpoint?:
No.

References:

A-14 Preliminary Science Report, p 91, 244-246.

S. Jacobs, R. E. Durkee, and R. S. Harris, Jr., Lunar Dust Deposition Effects on the Solar Absorptance of Thermal Control Materials, AIAA paper 71-459, AIAA 6th Thermophysics Conference, Tullahoma, TN, April 26-28, 1971

Apollo 14 Final Lunar Surface Procedures, JSC, December 31, 1970

Apollo 14 Technical Crew Debriefing 17 February 1971, in the JSC History Office.

Apollo Stowage List - Apollo 14, MSC, 9 February 1971.