Determine eclipse events, which occur when the Sun or Moon is blocked, typically from the point of view of an Earth observer.
Compute the date and properties of an eclipse:
Get the next eclipse occurring after a given date:
Specify a point from which an eclipse should be visible:
Plan the observation of meteor showers, which are annual events that have various activity rates.
Get information about a meteor shower:
Do computations with meteor shower properties:
Calculate the time of sunrise and sunset, which varies throughout the year, from one location to the next.
Compute sunrise/sunset times:
Compute sunrise/sunset times for a specified date:
Predict the longest and shortest days of the year, which happen during the summer and winter solstices, and observe that on the spring and autumnal equinoxes, the Sun rises and sets due east and west, respectively.
Computes the dates of solstices and equinoxes:
Witness the growing and shrinking phases of the Moon throughout the month as the amount of illumination from the Sun, as observed from Earth, changes.
Get information about lunar phases:
Find out when a phase will occur:
Find the Moon's phase on a particular date: