An interception or obscuration of the light of the sun,
moon, or other luminous body, by the intervention of some other body,
either between it and the eye, or between the luminous body and that
illuminated by it. A lunar eclipse is caused by the moon passing
through the earth’s shadow; a solar eclipse, by the moon coming between
the sun and the observer. A satellite is eclipsed by entering the
shadow of its primary. The obscuration of a planet or star by the moon
or a planet, though of the nature of an eclipse, is called an
occultation. The eclipse of a small portion of the sun by Mercury or
Venus is called a transit of the planet.