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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 577 records · Page 32
All sourcesNASA NTRSDOE OSTI
NASA NTRS1967

The winter helium bulge.

Diurnal atmospheric density bulge shifts observed by Explorer, showing latitudinal-seasonal variation in helium concentration

ATMOSPHERIC DENSITY↗
NASA NTRS1968

The winter helium bulge.

Diurnal atmospheric density bulge shifts observed by Explorer, showing latitudinal seasonal variation in helium concentration

Keating, G. M.↗
NASA NTRS1971

Joint measurements of wind and temperature structure in the winter mesosphere at high latitudes

An attempt to identify propagating internal gravity waves in the mesosphere was made by sounding the region with three instrumented rockets on January 13-14, 1970, from Churchill, Canada (59 N). The three observations, which were conducted at approximately 90 min. intervals, consisted of a pitot probe bracketed by two acoustic grenade soundings. Thus, two temperature and wind profiles and one density profile were obtained independently, permitting an examination of the thermodynamic structure and the wind structure. The results of the combined thermodynamic and wind observations were found to be quantitatively compatible with a gravity wave interpretation. This interpretation also predicts vertical velocities on the order of 10/msec in the 80 km region.

Eberstein, I. J.↗
NASA NTRS1972

Application of ERTS-1 imagery to the study of caribou movements and winter dispersal in relation to prevailing snowcover

The author has identified the following significant results. Habitat differentiation was determined feasible using output from MSS band 6 because of apparent high correlations between surface moisture and habitat type on the test area. Progressive early snow distribution was readily determined from MSS outputs, particularly bands 4 and 5. Approximately thirty thousand caribou migrated into the test area during the reporting period, and aerial reconnaissance data on distribution were obtained for selected areas within several days of satellite overflight.

Lent, P. C.↗
NASA NTRS1973

Application of ERTS-1 imagery to the study of caribou movements and winter dispersal in relation to prevailing snowcover

The author has identified the following significant results. Step-wise discriminate analysis has demonstrated the feasibility of feature identification using linear discriminate functions of ERTS-1 MSS band densities and their ratios. The analysis indicated that features such as small streams can be detected even when they are in dark mountain shadow. The potential utility of this and similar analytic techniques appears considerable, and the limits it can be applied to analysis of ERTS-1 imagery are not yet fully known.

Lent, P. C.↗
NASA NTRS1974

Application of ERTS-1 imagery to the study of caribou movements and winter dispersal in relation to prevailing snowcover

The author has identified the following significant results. A multiband classification scheme was applied to ERTS-1 MSS digital tape data in a portion of the Yukon Flats area. Primary analytic objectives of mapping the extent of recent wildfire burns and mature forest were realized illustrating application to moose and caribou biology. Additionally, the analysis indicated the presence of new lakes as well as disappearance of lakes present in 1956. Because this is an important waterfowl production area, similar analyses may have significant application potential to waterfowl biology for rapid updating of habitat information. Further field confirmation of this finding is required.

Lent, P. C.↗