The science of solar eclipses:
total or annular eclipses were shown schematically at North Down
on June 10 or Ridgeway on June 15, in relation to an
astronomical Saros cycle that lasts for 18 years and 11 days
How might this work? Well, the synodic cycle of our Moon lasts
for 29.53059 days, and describes different phases such as new,
crescent or full. Meanwhile, the draconic cycle of our
Moon lasts for 27.21222 days, and describes when it passes
through an imaginary plane defined by Earth and Sun. When those
two cycles coincide, we can see an eclipse!
It turns out that synodic cycle
multiplied by 223 months equals precisely the draconic cycle
multiplied by 242 months. In other words (29.53059 x 223) =
6585.32 days, while (27.21222 x 242) = 6585.36 days. The whole
number 6585
equals 18 years and 11 days, but we still have
one-third of a day left over. That is because both
calculated values end in decimal fractions of 0.32 or
0.36, which lie close to 0.33 or one-third (see
http://eclipse.gsfc.nasa.gov/SEsaros/SEsaros.html).
Thus from a theoretical perspective, one might expect to see the
same kind of solar eclipse once every 18 years and 11 days. Yet
each successive eclipse should be located one-third of a day (or
120 degrees of longitude) further around the Earth than its
predecessor. That seems to be what those crop artists were
trying to teach us at North Down on June 10, 2008:
There we can see planet Earth
looking down from the North Pole, as shown previously at West
Kennett Longbarrow on June 9 (Click
HERE ). The geographical locations of three successive
eclipses within any 18-year Saros cycle have been labelled as
"t1, t2, t3" or as "a1,
a2, a3". Those three symbols
"t" represent total solar eclipses, where all light
from our Sun is blocked completely by the Moon (upper
right). Those three symbols "a" represent annular solar
eclipses, where only some of the light from our Sun is blocked
by the Moon, leaving a bright ring or annulus (lower right).
In each case, any successive
eclipse from an 18-year Saros cycle (say "t2" versus "t1", or
"a2" versus "a1") lies one-third of the way around the world
from its predecessor.
A fairly similar crop picture appeared five days later at
Ridgeway on June 15, 2008:
On
the left above, we can see how total versus annular solar
eclipses are produced: the Moon in one case lies closer to Earth
than in the other, thereby producing a broader shadow. On the
right above, we can see two outer rings of small balls that tell
how far the Moon lies from the Earth for any kind of solar
eclipse. A somewhat distant ring is shown for "annular", while a
somewhat close ring is shown for "total".
Next, at the centre of that same crop picture, we can see six
large circles which were clearly meant to represent six
successive Saros cycles: three for total, and three for annular
(see North Down above). Each large circle has been surrounded by
18 small dots to symbolize "18 years".
North Down and Ridgeway were the latest in a series of
eight crop pictures from April to mid-June of 2008 to
describe various aspects of eclipse science, in apparent
anticipation of a total solar eclipse on August 1, 2008. The
others appeared at Riesi (Italy) on April 20, Hackpen Hill on
May 24, West Kennett on June 6, West Kennett Longbarrow on June
9, Lizzano (Italy) on June 12, or Uffington on June 13. The sum
total of those many different crop pictures seems very
impressive indeed, and far beyond the intellectual or
technological capabilities of any hypothetical human fakers to
produce.
Red Collie
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