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Langseth, M. G., Jr.

Publications and source records attributed to Langseth, M. G., Jr..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Heat flow experiment

The heat flow experiment conducted during the Apollo 17 flight in the Taurus-Littrow area of the moon is discussed. The concept of the experiment is based on the direct measurement of the vertical flow of heat through the regolith. The measurement is made far enough below the surface so that the time-varying heat flow resulting from the very large diurnal variations of the surface temperature is small as compared with the flow from the interior. The equipment used for the experiment is described and illustrated. Graphs are developed to present the results of heat flow and surface temperature measurements.

Langseth, M. G., Jr.↗
NASA NTRS1973

Surface brightness temperatures at the Apollo 17 heat flow site - Thermal conductivity of the upper 15 cm of regolith

Lunar surface brightness temperatures derived as part of the Apollo 17 heat flow experiment are reported. Nighttime surface temperatures, calculated from the data provided by two thermocouples suspended about 15 cm above the lunar surface, are used to determine the conductivity profile of the upper 15 cm of regolith at the ALSEP site. The surface reaches a maximum temperature of 384 (plus or minus 6) K at lunar noon and cools to a minimum temperature of 102 (plus or minus 1.5 K) at the end of the lunar night. Conductivities of the order of .000015 W/cm-deg K are postulated for a 2-cm porous surface layer overlying more compact regolith material with conductivities in the range of .0001 to .00015 W/cm-deg K between 2 and 15 cm. A mean surface temperature of 216 (plus or minus 5) K is deduced from the thermocouple data. The 256 K temperature measured by the probe sensors at 130 cm thus indicates that a large mean temperature gradient exists at the Apollo 17 site.

Keihm, S. J.↗
NASA NTRS1972

Heat flow experiment

The heat flow experiment installed on the lunar surface during the Apollo 15 flight is described. Subjects discussed are: (1) the experiment concept and design, (2) the operations of the experiment, (3) the employment of the experiment on the lunar surface at Hadley Rille site, (4) subsurface lunar temperatures, and (5) extrapolation of sensor temperatures to equilibrium values. Graphs of the data obtained from the experiment are provided.

Langseth, M. G., Jr.↗
NASA NTRS1972

Development of an in situ thermal conductivity measurement for the lunar heat flow experiment.

Discussion of the design and calibration of the heat flow experiment of the Apollo Lunar Scientific Experiments Package (ALSEP). The principal objective is to gain evidence on the bulk chemistry of the moon. The heat flow is determined by making independent measurements of the vertical temperature gradient and the thermal conductivity in the inner surface layer (the regolith). Attention is given to the errors associated with the experimental technique. The low thermal conductivity of the regolith layer presents both advantages and disadvantages in heat flow measurement.

Langseth, M. G., Jr.↗
NASA NTRS1970

Apollo 13 lunar heat flow experiment

Apollo 13 lunar surface heat flow experiment to measure vertical temperature gradients as function of time and soil thermal conductivity

Chute, J., Jr.↗