Scientific topics Astronomical information

Last updated:7 June 2023

Our products include almanacs, software and web services providing precise astronomical data.

Astronomical definitions

Sunrise is defined as the instant in the morning under ideal meteorological conditions, with standard refraction of the Sun's rays, when the upper edge of the sun's disk is coincident with an ideal horizon.

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Summer and winter solstice

A hemisphere's winter solstice is the shortest day of the year and its summer solstice the year's longest.

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Moon and planet information

For information related to planet rise and set times, and the phases of the moon, please refer to the United States Naval Observatory website.

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Sunrise, sunset and twilight times

Computes sunrise, sunset and twilight times using the National Gazetteer of Australia.

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Moonrise and moonset times

Compute Moonrise and Moonset Times. To use this facility you need to know the latitude and longitude of the location you want to calculate rise and set times for.

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Sun, moon azimuth and elevation

Compute Sun and Moon Azimuth & Elevation To use this facility you need to know the latitude and longitude of the location for which you want to calculate the azimuth and vertical angle.

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