Instrument Information
IDENTIFIER urn:nasa:pds:context:instrument:hfe.a17a::1.1
NAME HEAT FLOW EXPERIMENT
TYPE REGOLITH PROPERTIES
DESCRIPTION The Heat Flow Experiment (HFE), which was part of the Apollo Lunar Surface Experiment Package (ALSEP), was designed to determine the rate of heat loss from the lunar interior by temperature and thermal property measurements at the surface and in the subsurface. The experiment was carried on the Apollo 15, 16, and 17 missions and was essentially identical on all three missions. The experiment apparatus consisted of two probes connected by 8 meter long cables to an electronics box which was in turn connected by a flat ribbon cable to the ALSEP station. The astronauts would drill two holes with the Apollo lunar surface drill (ALSD). The ALSD was equipped with borestem caps and retainers, borestems, bore bits, a bore bit/drill adapter, a treadle, and a bore stem/core stem wrench. The borestem assemblies used in drilling consisted of lengths of hollow fiberglass tubes, 2.5 cm in diameter, which would be connected together as the drilling progressed, and remained in the holes to provide a casing to prevent collapse of the hole walls during insertion of the probes. Nominally the holes were to be drilled to a depth of 3 meters but in practice no holes reached this depth. The probe would be lowered down into the borestem until it came to rest on top of the drill bit at the bottom of the hole. The borestem tube would project out of the surface a distance dependent on the depth of the hole.
MODEL IDENTIFIER
NAIF INSTRUMENT IDENTIFIER
SERIAL NUMBER not applicable
REFERENCES Apollo 17 Preliminary Science Report, NASA SP-330, published by NASA, Washington, D.C., 1973.

Apollo Scientific Experiments Data Handbook, NASA Technical Memorandum X-58131, JSC-09166, published by NASA Johnson Space Center, Houston, Texas, Aug. 1974.

Keihm, S.J., and M.G. Langseth, Jr., Surface brightness temperatures at the Apollo 17 heat flow site: Thermal conductivity of the upper 15 cm of regolith, Proceedings of the Lunar Science Conference, 4th, Volume 3, pages 2503-2513, 1973.

Keihm, S.J., J.L. Chute, K. Peters, and M.G. Langseth, Apollo 15 measurement of lunar surface brightness temperatures - thermal conductivity of the upper 1 1/2 meters of regolith, Earth Planetary Science Letters, 19, No. 3, pages 337-351, July 1973.

Langseth, M.G., Jr., Lunar Heat-Flow Experiment: Final Technical Report: 6 Jun. 1966 - 30 Jun. 1975, NASA-CR-151619, CU-4-77, 289p, Lamont-Doherty Geological Observatory of Columbia University, Palisades, New York, 1977.

Langseth, M.G., Jr., S.P. Clark Jr., J.L. Chute, Jr., S.J. Keihm, and A.E. Wechsler, The Apollo 15 Lunar Heat-Flow Measurement, In The Moon, Volume 4, Issue 3-4, pages 390-410, 1972.

Langseth, M.G., Jr., S.J. Keihm, J.L. Chute, Jr., and A.E. Wechsler, Heat flow experiment, In Apollo 15 Preliminary Science Report, Section 11, NASA SP-289, published by NASA, Washington, D.C., 1972.

Langseth, M.G., Jr., S.J. Keihm, and J.L. Chute, Jr., Heat flow experiment, In Apollo 17 Preliminary Science Report, Section 9, NASA SP-330, published by NASA, Washington, D.C., 1973.

Langseth, M.G., Jr., S.J. Keihm, and K. Peters, Revised lunar heat-flow values, Proceedings of the Lunar Science Conference, 7th, Volume 3, pages 3143-3171, 1976.

Nagihara, M.G., Y. Saito, and P.T. Taylor, Reexamination Of the Apollo 15 Heat Flow Data Toward Understanding Potential Causes Of The Long-Term Subsurface Warming Observed, In: Abstracts of Papers Submitted to the 41th Lunar and Planetary Science Conference, Volume 41, Abstract 1353, 2010.