Astronomical calculations
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The Celtic Wheel Horologium — indicates the current positions of the sun, moon, and stars, as well as the date with respect to the solstices, equinoxes, and cross-quarter days. Use it to find the current sidereal and solar times, and the dates and times of the solar holidays and moon phases. |
An Old English Lunisolar Calendar — based on first quarter moons 🌓 beginning with the one before Yule. This evening will be .
Sunset Calculator — enter your latitude and longditude and get sunset times for the whole year.
Solar and Lunar Data — current moon phase () and relative size, and the positions of the earth and moon in their orbits. Solar Events Calculator — solstices, equinoxes, and cross-quarter days, all at your fingertips. Moon Phase Calculator — what moon phase were you born under? Moon Perigee and Apogee Calculator — find the next supermoon. |
Calculations are based on the “higher accuracy” equations in Astronomical Algorithms, second edition, by Jean Meeus, and the full VSOP87 data set.  They are much more accurate than spreadsheet calculations.
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Today is in the Maya long count calendar. |
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