Occultations occur when one celestial body passes in front of another.
These frequent and intriguing events are fun to watch, and provide an important way for amateur astronomers to make significant discoveries about objects within our own Solar System as well as the stars beyond.

On this site you will find information about different sorts of occultations, and how to contribute useful scientific results by observing occultations.
The site contains all the background information needed by someone new to occultation observing. It also provides more technical information of use to advanced observers.

The Trans-Tasman Occultation Alliance is also proud to represent the interests of the International Occultation Timing Association (IOTA) in the Australasian region.

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