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.
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 image below (at eclipse maximum), even a partial eclipse
can provide an impressive visual display.
Note: For the umbral shadow, click here.
(First contact) |
(First contact) |
(Start of Totality) |
Totality |
(End of Totality) |
(Full) |
(End) |
|
Body: Moon Mass: 0.0123 x Earth Mean Eq Diameter: 0.2719 x Earth Distance: 389,173 km Sidereal Rev: 27d 07h 43m 11s Age: 14d 18h 17m Diameter: 31.00' Saros Cycle: 138 Magnitude:
Duration:
|
|
Date: Aug 17, 2008 00:13:12 UT+3 Location: Athens, Greece Equipment: AP 160 f/7.5 StarFire EDF AP 1200GTO GEM Canon EOS 300D Exposure(s): 1 x 3.2 sec ISO 200 RAW image format 3072x2048 image size Manual Mode Software: Digital Photo Pro V2.1.1.4 Photoshop CS2 Processing: RAW to TIFF (16-bit) Conv Resampling JPG Compression |