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Hord, C. W.

Publications and source records attributed to Hord, C. W..

47 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Mariner 9 ultraviolet spectrometer experiment - Structure of Mars' upper atmosphere.

Mariner 9 observations of the limb intensity profile of the CO Cameron bands in the Martian airglow demonstrate the validity of a postulated relationship between the equivalent subsolar zenith intensity and the 10.7-cm solar radio flux. Comparison of averaged limb intensities of the CO2+ doublet and the Cameron bands on four favorable occasions is consistent with the intensities being directly proportional in a ratio of 0.24 to 1.

Stewart, A. I.↗
NASA NTRS1972

Mariner 6 and 7 ultraviolet spectrometer experiment - Photometry and topography of Mars.

From data obtained by the ultraviolet spectrometers aboard the Mariner 6 and 7 Mars missions the reflectivity of the illuminated disk of Mars was found to have two distinct spectral types, associated with polar and nonpolar regions. In this work the characteristic spectrum of nonpolar regions on Mars is discussed. An interpretation of the variation of the intensity at 3050 A due to surface pressure variations is given. A comparison of the ultraviolet observations with pressures inferred by the infrared spectrometer is used to test this interpretation and to determine physical parameters of Mars which lead to the observed reflectance. Earth based pressures obtained by broadening of the one-micron band of CO2 and radar topography are compared with the ultraviolet results.

Hord, C. W.↗
NASA NTRS1972

Mariner 9 ultraviolet spectrometer experiment - Initial results.

The UV airglow spectrum of Mars has been measured from an orbiting spacecraft during a 30-day period in November and December 1971. Significant variations in the scale height of the CO Cameron band airglow have been observed during a period of variable solar activity. The atomic oxygen and hydrogen airglow lines are present during all the observations. Measurements of the reflectance of the lower atmosphere of Mars show the spectral characteristics of particle scattering and a magnitude that is about 50% of that measured during the Mariner 6 and 7 experiments in 1969.

Barth, C. A.↗
NASA NTRS1971

Mariner 7 ultraviolet spectrometer experiment - Photometric function and roughness of Mars' polar cap surface.

Review of some of the results of the Mariner 7 ultraviolet spectrometer observations of the south polar cap of Mars. The near ultraviolet polar spectrum shows the predominance of surface reflection over atmospheric scattering. The intensity of the reflected radiation decreased steeply for a change in solar elevation of only about 10 deg. Neither a haze layer nor ground inhomogeneity is considered a likely explanation for this observation. An unusual photometric function of the surface is more probable. An analysis of reflected radiation intensity as a function of incidence and emission angles was made, assuming a photometric function for the surface. The angular inversion revealed a 'smoothness factor' suggestive of an icy or glazed surface. A hypothesis is advanced to explain the observed phenomena and associated polar features.

Pang, K.↗
NASA NTRS1969

Ultraviolet spectroscopy

Ultraviolet spectroscopic measurements on Mars upper atmosphere by Mariners 6 and 7

Anderson, G. P.↗