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Lane, A. L.

Publications and source records attributed to Lane, A. L..

83 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Mariner 9 ultraviolet spectrometer experiment - Seasonal variation of ozone on Mars.

Ozone is observed to be present in the polar regions of Mars and to have a seasonal variation. In the summer, the amount present in the polar atmosphere is less than 3 micrometer-atmospheres. In the fall, ozone increases in amount and is found in association with the formation of the polar hood. In winter, the maximum amount of ozone is present, 57 micrometer-atmospheres over the polar hood and 16 over the polar cap. In spring, the amount over the polar cap decreases monotonically until by the beginning of summer the ozone disappears. Ozone is not observed in the equatorial region during any season.

Barth, C. A.↗
NASA NTRS1973

Mariner 9 Ultraviolet Spectrometer experiment - Observations of ozone on Mars.

The Mariner 9 Ultraviolet Spectrometer has observed the 2550 A ozone spectral absorption feature on Mars. This absorption was previously detected in the south polar region by Mariner 7 in 1969. Mariner 9 did not observe ozone at any time in the equatorial region, nor at the south polar cap during its summer season. However, ozone was found in the north polar region beginning at a latitude of 45 deg N and extending northward. Ozone later appeared in the southern hemisphere southward of 50 deg S as the Mars autumnal equinox approached. The presence of ozone on Mars seems to be coupled to the water vapor content of its atmosphere.

Lane, A. L.↗
NASA NTRS1972

Mariner 9 ultraviolet spectrometer experiment - Photometry and topography of Mars.

Reflectance properties of Mars were measured in a 100-A band (centered at 3050 A) by the UV spectrometer on board Mariner 9 during the period from Nov. 14, 1971 to Mar. 1, 1972. A topographic map of Mars based on the scattering of UV light from the Mars atmosphere (after clearing of the dust storm) is illustrated. The UV light which is Rayleigh-scattered by the Mars molecular atmosphere (with allowance for uniform turbidity) is proportional to surface pressure regardless of the atmospheric temperature structure. Comparison with Mariner 9 radio occultation measurements determines the fraction of total reflectance that is due to atmospheric scattering.

Hord, C. W.↗
NASA NTRS1972

Mariner 9 ultraviolet spectrometer experiment - Mars airglow spectroscopy and variations in Lyman alpha.

Mariner 9 ultraviolet spectrometer observations show the Mars airglow consists principally of emissions that arise from the interaction of solar ultraviolet radiation with carbon dioxide, the principal constituent of the Mars atmosphere. Two minor constituents, atomic hydrogen and atomic oxygen, also produce airglow emissions. The airglow measurements show that ionized carbon dioxide is only a minor constituent of the ionosphere. Using the airglow measurements of atomic oxygen, it is possible to infer that the major ion is ionized molecular oxygen. The escape rate of atomic hydrogen measured by Mariner 9 is approximately the same as that measured two years earlier by Mariner 6 and 7. If the current escape rate has been operating for 4.5 billion years and if water vapor is the ultimate source, an amount of oxygen has been generated that is far in excess of that observed at present. Mariner 9 observations of Mars Lyman alpha emission over a period of 120 days show variations of 20%.

Barth, C. A.↗
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 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 NTRS1972

Mariner 9 ultraviolet spectrometer experiment - Stellar observations.

Photoelectric spectra have been obtained for a number of early-type stars in the 1100- to 2000-A region with the Mariner 9 UV spectrometer. The resonance lines of H I, Si IV, and C IV are easily identified, as are features due to C II, C III, Si III, Fe II N IV. The absolute energy distribution derived from the data lie about 20% below those of OAO-2 in the 1200- to 2000-A region.

Lillie, C. F.↗