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NFC: Lunar Eclipse Tonight

The Total Lunar Eclipse - January 20, 2000

During the evening hours of January 20, 2000 and early morning hours of
January 21, 2000 a lunar eclipse will be visible from
North and South America. During this time, the moon will slip into the dark
umbra shadow of the Earth and will disappear in the
night sky. The full moon will be a dark red and brown color for over an
hour and then slowly reappear over the next hour. If we
have clear sky, many colors of orange and red can be seen as the light from
the Sun is refracted through the Earth's atmosphere
and shines on the moon.

Lunar Eclipse Timing

Time specifics for the Eclipse (note these times are in Universal Time and
the date for them is January 21, 2000).

       Umbra contact 3:01.30 UT
       Full Eclipse 4:04:37 UT
       End of full eclipse 5:22:24 UT
       Last Umbra contact 6:25:30 UT

To convert UT to your local time, subtract the number of longitude hours
(or time zones) to the West you are located from the zero hour position at
Greenwich England. As an example, for central Ohio where the Eastern
Standard Time system is used (same as New York), subtract 5 hours from the
UT value to obtain the local time. Continuing across the USA, subtract 6
for Central Time, 7 for Mountain Time, and 8 for Pacific Time.


Local Circumstances (Central Ohio)

       Umbral contact starts at 10:01:30 EST
       Total start at 11:04:37 EST
       Mid-eclipse at about 11:44 EST
       Total ends at 12:22:24 EST
       Umbal contact ends at 1:25:30 EST

Totality will last 1 hour and 18 minutes. The northern half of the moon
will be more immersed in the Umbra shadow of the
Earth. As a result it will appear darker than the southern half of the
moon. It is said that one can see over 40 different shades of
orange and red during a lunar eclipse. This one will present a wide
variation in colors. At an altitude of 50 to 70 degrees you
should have no problem locating a suitable observing spot. A very dark site
is not needed, but to fully appreciate all the color
variations you should be in a place where your eyes become dark-adapted.

Data adapted from F.Espenak, NASA/GSPC, for a more accurate plot of this
information, visit the following web site.

http://sunearth.gsfc.nasa.gov/eclipse/Leplot/LE2000Jan21T.gif

When will the next lunar eclipse be visible in Ohio? - May 16, 2003

Where is a good place to see the eclipse this time? - Almost anywhere. It
will be high in the sky and except for the darkest
portion of eclipse it will be easy to spot, even from a light polluted
located. However, the best place to see the eclipse will be
from a dark area with a good view to the South-East and South. In
Central-Ohio Perkins Observatory will be open for "Friends
of Perkins" members only however CAS members with telescopes are always
welcomed! Another good place for CAS members
will be the dark sky site in South Eastern Ohio as well as other places
affording minimal light pollution. But for most people, the
simplest answer to this is to go outside between 10PM and midnight to see
the partial then total phases of the eclipse.

 Why isn't there a lunar eclipse every time there is a full moon? - The
moon's orbit is inclined relative to the ecliptic
(apparent orbit of the sun) by 5 degrees. The moon is only a half-degree in
size and the shadow (umbra) is one and a half
degrees in size. The moon must be within three-quarters of a degree of the
ecliptic in order to have a lunar eclipse. With a
deviation of five degrees that means that most full moons appear when the
moon is more than the minimum distance from the
ecliptic.

 Why does the Moon appear orange, red, and brown? - Light traveling through
the atmosphere of the Earth is refracted.
The light that gets refracted is the slim amount that goes through the
atmosphere and never hits the ground or water. The light
travels though the atmosphere and is bent like a prism so that a spectrum
is cast into space. The red portion of the sunlight is
refracted more than the blue and thus the moon takes on a reddish glow.
Towards the center of the umbra there is less refracted
light and this is why the moon is very dark there.

How fast does the moon move? - During an eclipse, the relative motion of
the moon is quite visible to the observer. Especially
with a telescope focused on a crater at high power. The moon moves at about
one half of a degree per hour in the sky relative to
the background stars.


Mark Binkley
Columbus Ohio USA            <))><
mbinkley at earthling_net