Free Astronomical Software

Julian Day Converter by gedesoft

This utility can convert a gregorian date into julian day format/Modified Julian Day format and vice versa. The Julian Day Format counts the day since the 24th november -4713bc. The julian day format is often used in the astronomical section to calculate for example rises.

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Adastra FREESTAR by Coeli Software Products

Experience accessible astronomy with a real-time sky, comprehensive reports, arcsecond accuracy, and exciting events such as animation and live tracking. Easy mouse-manipulation of the sky brings planets, comets, asteroids, DSOs, and a multitude of stars to your fingertips in real-time. And let TimeLine graphically show the effects of precession down through the millennia...

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