Lunar occultation observation

IOTA/EA provides prediction of lunar occultation, disseminates observation methods, and accepts observation reports.

What is Lunar occultation?

The moon moves around the celestial sphere with a period of about 27 days. During its motion, moon  sometimes hides stars behind itself. These phenomena are called Lunar occultation. By observing these phenomena, we can determine and verify the relative positions of the Moon and stars precisely.

What is the grazing occultation?

In the special case of the occultation, when the edge of the moon passes through a star as if it were snatched by it, the star is seen to be hidden and revealed several times by the mountains and valleys of the moon. By observing this phenomenon, called grazing occultation, we can precisely verify the position of the Moon in ecliptic latitude.

Inquiries and observation reports should be sent by e-mail to the following address.

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Lunar occultation prediction

Lunar occultation prediction for East Japan

Lunar occultation prediction for West Japan

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