I had great views of Titan's shadow transit, but only after the good luck
defeated the bad.
Good luck: My 22" Starmaster arrived last week, two months earlier than I
had dared hope. It's a marvelous instrument; picking off galaxies in Virgo
is like taking candy from a baby compared to my venerable 8" Orion.
Bad luck: I didn't get home until after 10 pm, leaving little time for
collimation and cooling. Collimation is a rather big deal at f/3.3.
Good luck: "Home" is at 2400 feet, on Skyline Blvd not far from Oak Ridge
observatory. The fog obediently stayed in the valleys until after midnight.
Bad luck: The tracking drive's battery died after a few minutes.
Good luck: The second battery was inexplicably charged.
In the end I had over an hour of observing time across two hours. Seeing
was good enough, improving during the first hour as the optics cooled,
then deteriorating again as Saturn sank lower and the fog crept higher.
Titan's shadow was immediately apparent, and lost to bad seeing at 230x
less than 5% of the time. Over the course of two hours it moved from near
the "right" limb to somewhat past the center. It took me at least ten
minutes to remember this was not a transit but rather a shadow transit,
and that the bright yellowish Titan-like spot nearby was in fact Titan
itself.
My sketch of the field includes two cloud bands, the rings' shadow cast on
Saturn, Saturn's shadow cast on the rings, and four moons in addition to
Titan. Tethys and Dione were "below" the "right" side of the rings; they
too moved noticeably with that as a reference, towards Saturn and in the
same direction as the shadow.
As the haze gathered around the Moon I trained my new telescope on it for
the first time. The unfiltered light from the eyepiece was like a
flashlight beam; teardown was delayed for several minutes as my vision
recovered. Looks like the old 8" is still good for something.
-- Greg Parker gparker-tac@No-Spam --- May 30, 2009: TAC Web Page Updated http://observers.org/TAC.cgi/Announcements/ GSSP is coming - June 20th: http://www.goldenstatestarparty.blogspot.com TAC mailing list - to join, manage, or leave: http://nine.pairlist.net/mailman/listinfo/tacReceived on Sun May 31 03:36:51 2009
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