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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Geologic remote sensing study of the Hayden pass-Orient Mine Area, Northern Sangre de Cristo Mountains, Colorado

Remote sensor data from a NASA Convair 990 radar flight and Mission 101 and 105 have been interpreted and evaluated. Based on interpretation of the remote sensor data, a geologic map has been prepared and compared with a second geologic map, prepared from interpretation of both remote sensor data and field data. Comparison of the two maps gives one indication of the usefulness and reliability of the remote sensor data. Color and color infrared photography provided the largest amount of valuable information. Multiband photography was of lesser value and side-looking radar imagery provided no new information that was not available on small scale photography. Thermal scanner imagery proved to be a very specialized remote sensing tool that should be applied to areas of low relief and sparse vegetation where geologic features produce known or suspected thermal contrast. Low sun angle photography may be a good alternative to side-looking radar imagery but must be flown with critical timing.

Wychgram, D. C.↗
NASA NTRS1975

de Sitter's theory 'melts' Europa's polar cap

In photoelectric observations of a series of occultations of the Jovian satellite Europa by the Jovian satellite Io it was observed that increasingly larger fractions of the north polar region of the former were covered at mid-event with each successive occultation. One of the possible explanations of the observed phenomena involves the existence of a bright north polar cap for Europa. The reported investigation shows that a second explanation may be more plausible. This explanation is related to the possibility that at mid-event the projected minimum distance between the centers of the satellites was smaller than predicted by Sampson's theory.

Aksnes, K.↗
NASA NTRS1975

On the interpretation of observed data from C-dE/dx detectors

The paper describes a Cerenkov detector system designed to obtain abundances and energy spectra of cosmic ray nuclei above charge 12 and above 350 MeV/nucleon. The detector system consists of three pulse ionization chambers, a Lucite Cerenkov counter and a plastic scintillation-counter hodoscope. The data analysis follows from the standard dE/dx-C technique. It is shown that by using the relativistic ionization rise, the resolution and pulse height corresponding to charged particles of Beta ? 1 in Cerenkov detectors can be determined. Least-squares-fit procedures are used to obtain area and time variations of detector response from flight data and to extract elemental abundances from data with charge resolution of roughly 0.3 charge units.

Benegas, J. C.↗
NASA NTRS1976

An algebraic approach to image de-smearing: Symmetries of polynomials and their zeros

Frequently a photograph received from a spacecraft will be smeared by some process, e.g., by camera motion. Algebraically such smearing can be represented as p = sigma f, where sigma is the true picture, p is the received picture, and f is the smearing function. (p, sigma, and f are polynomials in two variables x and y.) Thus, in principle, sigma can be recovered by multiplying p by 1/f. However, there are problems involved in computing 1/f. Some of these problems are investigated.

Johnson, D. L.↗