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Greetings
Kansas was blessed with clear crisp skies and I led some of my students and
parents from Northwest MS , Kansas City, KS, , by school bus down to the
local Powell observatory in Louisburg, 20 minutes south of Kansas City. When
we got there the eclipse had already started. Students viewed through the 25
inch telesope and other scopes set up around the observatory.
One of my students was featured in the Kansas City Star newspaper, observing
through the big scope. Students and parents were also on the local channel 5
news.
I also had them rate the eclipse according to the Danjon scale (see below)
and draw pictures of the eclipse as a little research project.
Several parents were surprised to see several meteors as well and viewed
Jupiter and other objects while I pointed out to them the constellations.
I am currently getting ratings from
ot 攀 琀栀攀椀爀 攀猀琀椀洀愀琀攀 漀昀 琀栀攀椀爀 爀愀琀椀渀最猀 ⠀猀攀攀 猀挀愀氀攀 戀攀氀漀眀
⤀ 眀栀椀挀栀 眀椀氀氀 戀攀 瀀漀猀琀攀搀⸀ 䰀攀琀 洀攀 欀渀漀眀 礀漀甀爀 氀漀挀愀琀椀漀渀 眀
栀攀爀e you observed if you send in your ratings.
I also took video with my sony and it came out rather well but not very
colorful though. This is the first time I took a video of a lunar eclipse (I
have videotaped the 1998 and 1999 with great success). I will place some
pics on my site and post the results on the listserves and in my newsletters.
thanks
Dr. Eric Flescher,webmaster, Eric's Black Sun Eclipse -
http://members.aol.com/kcstarguy/blacksun/eclipse.htm -Editor,
Blacksuneclipse newsletter - to subscribe send email to
blacksuneclipse-subscribe@egroups.com
Gifted education consultant- Piper HS; Northwest MS, Coronado MS (Kansas
City, KS)
Q: What is the Lunar eclipse darkness measuring scale?
A: One of the simplest and most telling total lunar-eclipse observations is
estimating the Moon's luminosity value at various times during totality.
Early in the twentieth century, the French astronomer André-Louis Danjon
devised a clever five-point scale for rating the darkness of a total lunar
eclipse. The Danjon scale, reproduced in Table 4.1, has since gone on to
become the standard by which all total eclipses are judged.
Table 4.1
Danjon Lunar Eclipse Luminosity Scale
L = 0.0 Very dark eclipse. Moon almost invisible, especially at
mid-totality.
L = 1.0 Dark eclipse, gray or brownish coloration; lunar-surface
details distinguishable only with difficulty.
L = 2.0 Deep red or rust-colored eclipse; central part in the umbra
dark, but outer rim of the umbra relatively bright.
L = 3.0 Brick-red eclipse, usually with a brighter (frequently
yellow) rim to the umbra.
L = 4.0 Very bright copper-red or orange eclipse, with a bluish,
very bright umbral rim.
The Danjon scale should be used to estimate the appearance of a total
eclipse only with the naked eye. Surprisingly, the often-subtle colors of
a total eclipse tend to fade as magnification increases. The late Joseph
Ashbrook suggested that this might be due to a reduction in surface
brightness to near or below the threshold for color perception.
Although Danjon devised the scale to fit every lunar eclipse, it is rare
for an eclipse to match one of his descriptions exactly. Instead, most
seem to fall somewhere between two values - therefore, so should your
estimate. For example, at mid-eclipse, if the Moon appears a muddy-clay
color highlighted with a bright, almost yellow rim, then the Danjon
luminosity value would fall somewhere between 2.0 and 3.0. After carefully
examining the Moon's appearance, judge which description it most resembles,
then prorate the value accordingly. In this case, a luminosity value of
2.4 or 2.5 would seem most appropriate. Astronomical magazines always
encourage readers to send in their observations and reports, but to be of
real value, always include your time, location, instrument used, if any,
and a description of the sky conditions.
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