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 image below (at eclipse maximum), even a partial eclipse can
provide an impressive visual display.
(First contact) |
(First contact) |
(Start of Totality) |
Totality |
(End of Totality) |
(Full) |
(End) |
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Body: Moon Mass: 0.0123 x Earth Mean Eq Diameter: 0.2719 x Earth Distance: 394,772 km Sidereal Rev: 27d 07h 43m 11s Age: 14d 19h 20m Diameter: 30.36' Saros Cycle: 119 Magnitude:
Duration:
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Date: Aug 07, 2017 21:20:21 UT+3 Location: Athens, Greece Equipment: AP 160 f/7.5 StarFire EDF AP 1200GTO GEM Canon EOS 5D Mk I AP 2x Conv Barlow Exposures: 1 x 1/13 sec ISO 200 RAW image format 4368x2912 image size Manual Mode Servo Mode Software: Canon FileViewer V4 Photoshop CS2 Processing: RAW to TIFF (16-bit) Conv Resampling JPG Compression |