Planet’s Visibility presents a 3-color graph that shows when a planet, the moon or the sun is visible during any year from 3000 BC to AD 6000 at any location on the earth. The vertical axis marks the months of the year, the horizontal axis marks the hours of the day. The three colors create a contour map effect and show whether the body is under the horizon (black) and invisible, above the horizon with the sun (light color) and invisible, above the horizon without the sun (shaded color) and so possibly visible. The times of sunrise and sunset can be shown on all the diagrams. By moving the mouse over the diagram, the date and time along with the object’s altitude, azimuth, and magnitude, or the phase of the moon, are displayed. In addition, Planet’s Visibility computes the dates of visibility phenomena, first and last visibility, acronychal rising and cosmical setting, with much supplementary information. These phenomena are very useful for historical purposes. Since the computation of these phenomena is complex and uncertain, alternate methods are provided and parameters can be altered by the user to find what appear to be the best results. There are also diagrams of solar and lunar eclipses, of the rotation, inclination, illumination, and apparent size of the bodies, and of Jupiter’s satellites. The settings for the computations may be saved, the graphics may be saved, pasted into documents, and printed, and the tables for visibility phenomena may be accumulated, edited, printed, and saved as .rtf files to be pasted into documents and printed.
Documentation is available.