Twilight Intensity at 20 Degree Elevation. Results of Observations
Abstract
A total of about 100 twilights were recorded, mainly between September, 1959, and September, 1960, with a few up to November, 1961. The results at 20 degrees elevation are presented in chronological sequence in the form of logarithmic intensity gradients, color ratios and absolute green intensities, all as functions of the sun depression. Weather maps and cloud cross-sections along the path of the setting (or rising) sun provide some information on possible cloud interference. Daytime turbidity data, visual purple light observations and astronomical data are also given. Details of the measurements, evaluation procedures and data reduction are discussed, together with procedures and results of instrument calibrations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1961
- Accession Number
- AD0273857
Entities
People
- F.e. Volz