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Post-Eclipse Update: Here is a mid-eclipse photo
from my back porch.
Multiple eclipse images seen in tree shadow - Joe Cahak
It's finally here - the Great North American total solar eclipse of 2017! The
amateur astronomy community has been anticipating and preparing for the event for
a couple years. Astronomy magazine (to which I subscribe) dedicated the entire
August issue to providing detailed information on viewing suggestions along the
entire path. Traffic from the Pacific Coast of Oregon to the Atlantic Coast of South
Carolina will probably be a challenge as people vie for positions as close to the
centerline as possible. Those who manage optimal locations will see about 2 minutes
and 40 seconds of total darkness. Others within the 68-mile-wide path of totality
will see from a fraction of a second up to the full extent.
According to a calculator on the
Vox website, we in Erie will only see a 76.2% eclipse, which will
barely darken our skies. The app on the webpage detects your location and displays
an animation showing the moon's transition across the sun, with an approximation
of the relative degree of darkness as it passes. According to astronomers who have
witnessed many solar eclipses in varying degrees of totality, you need to be within
about 95% to have a very noticeable change in light level. They compare it to a
dark cloud moving in front of the sun. By comparison, a full moon at perigee reflects
around 12% of the sun's light.
Melanie and I had planned to drive the 475 miles down to South Carolina to view
the eclipse in the path of totality, but won't be able to go so we'll just have
to rely on reports of others. Bummer. If I manage to live until April 8, 2024 -
a mere 6-½ years away, the next total solar eclipse will run right through
my back yard (see 2024 eclipse map to right). That will be convenient.
 Amateur radio operators have a full slate
of events, tests, and measurements planned for the day. Visit the
ARRL website for information about the
Solar Eclipse QSO Party and other goings on. Data regarding propagation
properties along the path of totality will provide indirect observation of ionospheric
activity in the various layers. Will the F1 and F2 layers which typically combine
at nightfall do so during totality? Direct measurements of the ionosphere were first
made in the 1950s, with much effort being expended during the International Geophysical
Year of 1957-58 (see "Electronics and the IGY,"
Part I and
Part II, in the February and March 1958, respectively,
Radio Electronics magazine). Measurements have been made previously during
total eclipses in other parts of the world, of course, but this is the first chance
American Hams have had the opportunity since February 6, 1979. Hams participated
in the August 31, 1932, total solar eclipse which crossed the United States, whereupon
a report titled, "Amateur Observations During the Total Eclipse of the Sun," appeared
in the January 1933 issue of QST magazine.
NASA has a web page
with tips for viewing the solar eclipse safely. I have a couple large pieces of#14
welders glass to use. Lots of stories have appeared recently about how to
protect your pets' eyes in case they're curious (or unlucky) enough
to look at the sun during the partial eclipse phases. Be sure to not let babies
or incapacitated people face the sun during that time, either. Finally, be vigilant
during the eclipse, especially during totality, since there are plenty of scumbag
people who will be roaming about looking for victims. Don't let the criminals exploit
what they believe will be a gun-free zone - if you get my drift!
Posted August 21, 2017
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