############################################################################## RISE / TRANSIT / SET TIMES TABLE For Most Solar System Bodies For Which a Topocentric Ephemeris is Possible AUTHOR : Jay Tanner - 2024 LANGUAGE : PHP v7.4.9 LICENSE : Public Domain ############################################################################## This program simply uses a simple brute force method to determine the rising, transit and settings times of the sun, moon, any planet or asteroid etc. A table is produced for each minute of the date, from which the rising and transit and setting times can be easily extracted to about the nearest minute. Standard refraction is applied. A simple table search can derive the time of some phenomena to within about the nearest minute, which is sufficient for most practical purposes. Different sources may give slightly different rising/setting times to within a minute or two, depending on the methods used to make the computations. Not every source does it exactly the same way, but they generally agree to within a minute or two. Temperature, atmospheric pressure, humidity and altitude all play a role in determining the precise rising, transit, and setting times of an astronomical body and those quantities are randomly variable and exact times impossible. However, the rise and set times do not have to be to-the-second precise if all you want to know is about what time to go out looking for a particular object in the sky. ----------- RISING TIME The rising time is found by finding the time when the numerical sign of the horizon elevation of the body changes from negative to positive. ------------ TRANSIT TIME The transit time is found by finding the time when the numerical sign of the local hour angle of the body changes from negative to positive. ------------ SETTING TIME The setting time is found by finding the time when the numerical sign of the horizon elevation of the body changes from positive to negative. All three of these times can be found by simply inspecting an internal work-table.