The Apollo 15 lunar heat-flow measurement

Langseth, Marcus G.; Clark, Sydney P.; Chute, John L.; Keihm, S.; Wechsler, A. E.

doi:10.1007/bf00562006

Cited by 120 publications

(104 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Results obtained in this study agree to within a few percent with the results by Langseth et al [1972bLangseth et al [ , 1973, except for the measurement at TG12A, which is off by 23 percent. Best fit values for the contact conductance H are also satisfactorily reproduced, which is slightly surprising given the relatively crude estimates which had to be used for the thermophysical probe properties.…”

Section: Resultssupporting

confidence: 86%

“…We have estimated the additional shunting caused by the compacted region using the model presented in section 2 and prescribing boundary conditions resulting in a thermal gradient of 1 K m −1 . We find that Langseth et al [1972aLangseth et al [ , 1972b have probably underestimated the thermal gradient by about 3%. However, considering other uncertainties connected to the thermal gradient measurement, this correction can be considered as negligible.…”

Section: Discussionmentioning

confidence: 62%

“…These are available in digital form at NASA's National Space Science Data Center [Peters, 2010], but the heating experiment data is fairly noisy. Therefore, we have decided to scan heating curves from the original publications [Langseth et al, 1972b[Langseth et al, , 1973.…”

Section: Resultsmentioning

confidence: 99%

“…[2] Lunar heat flow has been measured at the Hadley Rille and Taurus-Littrow sites during the Apollo 15 and 17 missions and values of 21 and 16 mW m −2 have been obtained [Langseth et al, 1972a[Langseth et al, , 1972b[Langseth et al, , 1973[Langseth et al, , 1976. Uncertainties for these values are given at ±15%, which mainly stem from the uncertainty connected to the regolith's thermal conductivity, although no rigorous error analysis was presented.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Apollo lunar heat flow experiment revisited: A critical reassessment of the in situ thermal conductivity determination

Grott¹,

Knollenberg²,

Krause³

2010

J. Geophys. Res.

View full text Add to dashboard Cite

[1] Lunar heat flow was determined in situ during the Apollo 15 and 17 missions, but some uncertainty is connected to the value of the regolith's thermal conductivity, which enters as a linear factor into the heat flow calculation. Different approaches to determine the conductivity yielded discordant results, which led to a downward correction of the obtained heat flow values by 30%-50% subsequent to the publication of the first results. We have reinvestigated likely causes for the observed discrepancies and find that neither poor coupling between the probe and regolith nor axial heat loss can explain the obtained results. Rather, regolith compaction and compression likely caused a local increase of the regolith's thermal conductivity by a factor of 2-3 in a region which extends at least 2-5 cm from the borehole wall. We conclude that the corrected lunar heat flow values, which are based on thermal diffusivity estimates sampling a large portion of undisturbed regolith, represent robust results. Future in situ measurements of regolith thermal conductivity using active heating methods should take care to both minimize regolith disturbance during probe emplacement and maximize heating time to obtain reliable results. We find that for the Apollo measurements, heating times should have exceeded at least 100 h, and ideally 200 h.Citation: Grott, M., J. Knollenberg, and C. Krause (2010), Apollo lunar heat flow experiment revisited: A critical reassessment of the in situ thermal conductivity determination,

show abstract

Section: Resultssupporting

confidence: 86%

Section: Discussionmentioning

confidence: 62%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Apollo lunar heat flow experiment revisited: A critical reassessment of the in situ thermal conductivity determination

Grott¹,

Knollenberg²,

Krause³

2010

J. Geophys. Res.

View full text Add to dashboard Cite

show abstract

“…The high heat flow [10] suggests that the high concentration of U is not just a near surface phenomenon but must extend to a depth at least as great as the thermal diffusion length, *** 100 -300 km. Therefore the enrichment of Ca, Al and U and probably the other refractories such as Ba, Sr, and REE occurs for a substantial fraction of the moon and may be a property of the moon as a whole.…”

Section: Composition Of the Moonmentioning

confidence: 99%

The composition and origin of the moon

Anderson

1973

Earth and Planetary Science Letters

View full text Add to dashboard Cite

show abstract

Interannual perturbations of the Martian surface heat flow by atmospheric dust opacity variations

et al. 2016

View full text Add to dashboard Cite

The InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission will perform the first Martian in situ heat flow measurement by deploying the Heat Flow and Physical Properties Package (HP3) onto the Martian surface. In order to estimate the heat flow coming from the planetary interior, HP3 will measure the local subsurface thermal gradient as well as the local thermal conductivity to a depth of up to 5 m. From these measurements, local heat flow can be determined, but this will in general differ from the heat flow emanating from the planetary interior due to atmosphere‐induced perturbations. Here we quantify heat flow perturbation induced by dust loading of the Martian atmosphere using dust opacity data obtained by the Mars Exploration Rover Opportunity. Dust opacity data span the time period between Mars year (MY) 27 and MY 32, thus incorporating the global dust storm event of MY 28 as a signal. We consider two end‐member cases for the regolith thermal conductivity and find that the background planetary heat flow is superposed by atmosphere‐induced perturbations of less than 1.5 mW m−2 at depths below 2 m if regolith thermal conductivity is low and around 0.025 W m−1 K−1 on average. If thermal conductivity is high and around 0.05 W m−1 K−1 on average, perturbations are less than 2.5 mW m−2 at depths below 3 m. Overall, the influence of interannual variability on subsurface heat flow is found to be moderate following a global dust storm. Considerably smaller perturbations are introduced by regional dust storms, which are of shorter duration and smaller magnitude.

show abstract

The Apollo 15 lunar heat-flow measurement

Cited by 120 publications

References 12 publications

Apollo lunar heat flow experiment revisited: A critical reassessment of the in situ thermal conductivity determination

Apollo lunar heat flow experiment revisited: A critical reassessment of the in situ thermal conductivity determination

The composition and origin of the moon

Interannual perturbations of the Martian surface heat flow by atmospheric dust opacity variations

Contact Info

Product

Resources

About