Eclipse - 15 June 11
- Beautiful darkest night
during a full moon
by Arvind Paranjpye (firstname.lastname@example.org)
Can I or my
students do some astronomical observations?
Yes of course. With
naked eyes, binoculars or low power telescope on can do exercises in
crater timing and estimating the eclipse darkness on Danjon scale.
Please visit NASA web site by Fred Espenak
Danjon Scale and
The map below shows the timings for the shadow to
cover and to leave different craters.
quick note on Danjon scale
The French astronomer Andre-Louis Danjon proposed a useful five
point scale for evaluating the visual appearance and brightness of the
Moon during total lunar eclipses. 'L' values for various luminosities
are defined as follows:
L = 0 Very dark eclipse.
Moon almost invisible, especially at mid-totality.
L = 1 Dark Eclipse, gray or brownish in coloration.
Details distinguishable only with difficulty.
L = 2 Deep red or rust-colored eclipse.
Very dark central shadow, while outer edge of umbra
is relatively bright.
L = 3 Brick-red eclipse.
Umbral shadow usually has a bright or yellow rim.
L = 4 Very bright copper-red or orange eclipse.
Umbral shadow has a bluish, very bright rim.
The assignment of an
'L' value to lunar eclipses is best done with the naked eye, binoculars
or a small telescope near the time of mid-totality.