Hostname: page-component-7479d7b7d-pfhbr Total loading time: 0 Render date: 2024-07-11T15:37:50.182Z Has data issue: false hasContentIssue false

Colorimetry of Martian features by means of area scanning

Published online by Cambridge University Press:  14 August 2015

Peter B. Boyce*
Affiliation:
Lowell Observatory, Flagstaff, Ariz., U.S.A.

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The contrast between light and dark areas on Mars has been the subject of two photoelectric studies by Younkin (1966) and McCord (1969), both of which were somewhat limited in scope. Younkin's data are based on one night's observations. McCord had a more suitable instrument for making a comparison between two areas on Mars, but still used only six nights. The agreement between these two studies is excellent. However, there is ample evidence from photographs that there are short-term changes in the contrast and brightness of Martian surface features, especially in the case of blue clearing. Visual observations are unsuitable for investigating these changes, due to the limited wavelength range of the eye's sensitivity, as well as the poor accuracy of the eye as a photometric instrument. Even photography is of limited usefulness when high accuracy is desired. Consequently, a program of continuous photoelectric observation of Mars was set up for the 1969 opposition. The technique of area scanning was chosen as the best method of recording the contrast of Martian surface features.

Type
Part II: Mars
Copyright
Copyright © Reidel 1971 

References

McCord, T. B.: 1969, Astrophys. J. 157, 79.CrossRefGoogle Scholar
Rakos, K. D.: 1965, Appl. Opt. 4, 1453.Google Scholar
Slipher, E. C.: 1962, The Photographic Story of Mars, Northland Press, Flagstaff.Google Scholar
Tull, R. G.: 1966, Icarus 5, 505.CrossRefGoogle Scholar
Younkin, R. L.: 1966, Astrophys. J. 144, 809.CrossRefGoogle Scholar