I'm pleased to announce that the first Drupal 7 compatible release of the Almanac module is available for download at http://drupal.org/project/almanac. It was developed and tested against the Alpha 3 release of Drupal 7, and the latest Drupal7 version of the Date API.
It retains the same functionality as the Drupal 6 version. What are the changes?
Updated 27 April 2010. details below.
An almanac providing basic sun and moon data can be a useful addition to sites that include astronomy, religious, education, energy-related, weather, or astrology information. Sites devoted to a range of outdoor activities, from night photography to fishing, can also benefit from adding an almanac.
PHP V5 includes sunrise and sunset functions to make the job of adding sunrise/sunset data easier. However, calculating the time of the rising and setting of the moon is more complex. The problems of calculating moonrise and moonset for a location - such as parallax, refraction, and accounting for days when there is either no moonrise or moonset - have been given exhaustive treatment elsewhere (just do a Google search on moonrise calculations.)
