The Fourth Day

The Fourth Day™ is an astronomical clock and almanac for your system tray (Windows 95 or later). An accurate 3D simulation of the Earth as lit by the sun is presented.

Enter your latitude and longitude, or select from over 23,000 database entries, and The Fourth Day™ will calculate the time of your sunrise and set, the start and end of civil twilight, and your local noon (when the sun is highest in the sky). Multiple user options allow for customization of the earth display, and you can set your PC's clock over the Internet using the master time server at the US Naval Observatory. Astronomy buffs will appreciate the real-time display of Julian Day, both local and Greenwich sidereal time, and correct display of moon phases.