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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 1,333 records · Page 74
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Atmospheric effects on ocean surface temperature sensing from the NOAA satellite scanning radiometer.

Investigation of the effects of atmosphere state, nadir angle, cloud amount, cloud height, and random noise on ocean surface temperature sensing from the NOAA series satellites. The results obtained include the finding that a 10% cloud cover can introduce errors that range from 0.5 K to 4 K depending on cumuloform cloud height, which makes necessary a complete cloud elimination in the analysis. A correction scheme for cloud-free conditions is developed that is essentially free of bias.

Maul, G. A.↗
NASA NTRS1974

Analysis of the Vertical Temperature Profile Radiometer (VTPR) radiometric problem

Variations in bias radiation, on the detector as a function of scan mirror position, are reported for the VTPR instruments presently in orbit. Tests in the laboratory show that this bias radiation disappears when optical baffles are added. A detailed analysis explains quantitatively the observed bias variation which is due to the extraneous field-of-view of the detector, and the variation in magnitude of the far field-of-view solid angle as a function of mirror position.

Goldberg, I. L.↗
NASA NTRS1974

Sensitivity of Josephson-effect millimeter-wave radiometer

The noise temperature and the minimum detectable temperature of a Josephson junction in video detection of microwave and millimeter-wave radiation has been calculated. We use the well-known method based on a Fokker-Planck equation. The noise temperature can be very close to ambient temperature. Because its predetection bandwidth is very wide, a Josephson-effect radio telescope receiver can have a minimum detectable temperature better than that of a traveling-wave maser.

Ohta, H.↗
NASA NTRS1974

Preliminary results of the Apollo 17 infrared scanning radiometer

The thermal emission of the lunar surface has been mapped by an infrared scanner from lunar orbit. Samples from approximately 250,000 scans reveal the full range of lunar temperatures from 80 to 400 K. The temperature resolution was 1 K with about plus or minus 2 K absolute precision. Spatial resolution was approximately 2 km over most of the horizon-to-horizon scan. The total mapped area amounted to approximately 30% of the lunar surface. The data currently available confirms the large population of nighttime thermal anomalies in western Oceanus Procellarum predicted by earth-based observations. Most of these 'hot spots' are associated with fresh impact features or boulder fields. Also seen in the data are 'cold spots' where the local nighttime temperature is depressed relative to the general soil background. Such regions exhibiting low surface conductivity are inferred to be relatively young, nonimpact features.

Mendell, W. W.↗
NASA NTRS1975

Limb radiance inversion radiometer

Engineering and scientific objectives of the LRIR experiment are described along with system requirements, subassemblies, and experiment operation. The mechanical, electrical, and thermal interfaces between the LRIR experiment and the Nimbus F spacecraft are defined. The protoflight model qualification and acceptance test program is summarized. Test data is presented in tables to give an overall view of each test parameter and possible trends of the performance of the LRIR experiment. Conclusions and recommendations are included.

Drozewski, R. W.↗
NASA NTRS1975

The development of an L-band radiometer dual-mode horn

An antenna was developed for the remote microwave measurement of ocean surface temperature during a flight test in a C54 aircraft. The basic antenna is a conical dual-mode horn similar to the dual-mode horn described by Potter (1963). The pertinent internal dimensions of the horn are given. The measured E and H plane patterns for the linearly polarized horn for a range of frequencies are shown in a graph.

Bailey, M. C.↗