The Great Asian Solar Eclipse of 2009
For images of the trip, see http://www.flickr.com/photos/41028395@N05/sets/72157621916039816/detail/
For images of the eclipse itself, see Greg Babcock's website at http://www.synrgistic.com/astro/
Here are some notes on the eclipse, including sky brightness measurements.
My wife and I brought along the trusty 3.5 inch Mak used
on several previous eclipses and large binocs to view the eclipse. These turned out to be ideal because the boat
was a bit more pitchy and rolly than a previous eclipse cruise and because the
coronal streamers were so smooth and extended.
Along with the visual effort, I also made sky brightness
and temperature measurements.
The eclipse lasted a total of 6 minutes 42.3 seconds, we
are told, longest until the year 2132.
At mid-eclipse, there was a defined pink horizon that
completely surrounded the boat, only a few degrees high, with very low cumulus
clouds in all directions.
Didn't seem that there were many clear locations to see
the eclipse, and we were in the middle of a great spot right at the point of
longest duration.
Mercury and Venus were easily visible as were most stars
to 2 magnitude (Betelgeuse, Rigel, et al).
There was a single diamond ring upon entry and a double
diamond ring upon exit.
I saw a nice red chromosphere upon entry, but none upon
exit.
The coronal streamers were very smooth and extended
several Sun diameters on both sides of the Sun in the big binocs.
I couldn't see any shadowbands on the light colored deck
and canvas coverings.
Temperature dropped from a high of 96F to 84F during the
eclipse.
Sky brightness readings in magnitude per square arcsecond were as follows:
1st measurable reading that I could obtain was 6.7 just
before 2nd contact
At 2nd contact, during the diamond ring, the sky brightness
was 12.72
2 minutes into the eclipse the reading was 13.22
3 minutes into the eclipse the reading was 13.19
At
mid-eclipse, the reading was 12.91
One minute before 3rd contact, reading was
12.54
45 seconds after 3rd contact, reading brightened to 6.9
After that, as before the eclipse, the sky was too bright to be measured
I also managed to see the morning green flash on eclipse
day. It was very brief, so my wife is
calling it the 'green snap'.
eod