Ever since man's first appearance on this planet, eclipses have been regarded as both mystical and devine with some cultures, for example, associating a lunar eclipse with the imminent arrival of death, war and/or famine. Although the distance of the moon and sun from earth vary dramatically (400,000 vs 150,000,000 km, respectively), the apparent size of these two heavenly bodies is such that they give the impression during an eclipse, solar or lunar, to be virtually identical (ie. about 30 arc-minutes in angular size). A total eclipse represents the unique occurrence in space and time where the sun, moon and earth are perfectly alligned as three collinear points on the same orbital plane. When the collinearity is not perfect but one of these three bodies is slightly higher or lower in the plane, we have a partial eclipse. Of course, a solar eclipse occurs when the moon lies perfectly between the sun and the earth, thus eclipsing the solar disk. In contrast, a lunar eclipse occurs when the earth lies between the sun and moon and, thus, the moon is hidden by the earth's shadow.

Note: Although total lunar eclipses are stunning events, partial eclipses involving the earth's penumbra and umbra are often considered non-events and not worthy of observation since the minute changes in the apparent magnitude of the moon are barely visible to the ground-based observer. However, as indicated by the digital mosaic image below, the partial entry of the full moon into the earth's (complete) shadow provided for an impressive and visible difference (the sequence below depicts the moon in the penumbra; the umbra; eclipse maximum; the umbra; and, finally, penumbra once again, respectively and represent successive exposures spaced 30 minutes apart).

Note: For a high-resolution image of eclipse maximum, click here.