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Younkin, R. L.

Publications and source records attributed to Younkin, R. L..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

The albedo of Titan

The irradiance of Titan has been measured from 0.50 to 1.08 micron in 30 A bandpasses spaced 0.01 to 0.02 micron apart. Geometric albedos have been computed at the wavelengths of measurement using a standard solar flux distribution after Labs and Neckel (1967). The maximum value of p sub lambda (0) is 0.37 at 0.68, 0.75, and 0.834 micron; the minimum value, in the centers of the strongest methane absorption bands, is 0.10 at 0.887 and 1.012 micron. The brightness of Titan at the time of the present measurements has been compared with that of previous modern photoelectric measurements. Within the apparent consistency of the different photoelectric systems, the brightness of Titan appears to undergo changes with time.

Younkin, R. L.↗
NASA NTRS1974

Titan photometric parameters

Measurements of the irradiance of Titan from 0.05 to 1.08 micrometer were carried out by 60-inch reflector, spectrometer, and pulse counting electronics. An approximate contour of the geometric albedo assumes methane is the principal absorber. The albedo of Titan reaches a maximum value of 0.37 at 0.68, 0.753, and 0.83 micrometers, while in the center of the strongest absorption features, at 0.89 and 1.0. micrometer, it falls to 0.10. Comparison with the methane bands of Jupiter and Saturn indicates that the maxima clearly do not represent the continuum and that the lower values may well be depressed by wings of methane bands adjacent to them.

Younkin, R. L.↗