Related Astronomy Links

Last Updated: May 02, 1999

Calculators

U.S. Naval Observatory's Sun & Moon Data For One Day
Calculates the times of sunrise, sunset, moonrise, moonset, transits of the Sun and Moon, and the beginning and end of civil twilight, along with information on the Moon's phase when given a date and location. They also have a calculator that generates a year's worth of sunrise and sunset, moonrise and moonset, and twilight times for a given location.
Sun Angle
Calculates solar angles based on the information you supply.
Universal Photoperiod Calculator
Calculates sunrise, sunset, length of day, declination, angle at noon with the information supplied.
Moon Calculator by Dr. Monzur Ahmed
Home page of MoonCalc, a free DOS program that calculates just about everything that can be including moonrise, moonset, phase, age, and much more.

U.S. Naval Observatory's FAQ
Before you go writing your calculator, visit the U.S. Naval Observatory's FAQ for definitions of sunrise, sunset, moonrise, moonset, etc. Also has sources of rise and set algorithms.
Astronomy Calculations FAQ for the Amateur
Contains pointers to online and offline sources of how to calculate astronimical events like sunrise and sunset.
sunriset.c (also at Snippets) by Paul Schlyter
A public domain C program that calculates sunrise, sunset, and the start/end of the different twilights.
Computing Rise/Set Times by Paul Schlyter
Paul Schlyer's tutorial on computing the rise/set/twilight times for the sun and the moon. Make sure to also visit his tutorial on computing planetary positions.

Solar Mike's Solar Electric & Photovoltaic System Resources
dedicated to photovolatic systems (for generating electricity). Includes a Javascript calculator, SolarScript, to help in designing PV systems, and a good collection of PV-related links.