Yes, it's that time of the lunation... the moon is waxing, it's visible in
the evening sky, and I churn a series of overwrought ORs. This time it's
even worse: I'm feeling fat and sassy after baggin several of Charles
Wood's 'L100' targets, including number 90. Watch out, he thinks he's God's
gift to lunar observing... ;-)
Observed the moon from 19:15 PDT until about 21:15.
Intes-Micro Alter M603 on a CG-5 mount.
Tele Vue Nagler eyepieces: 16mm, 7mm, 5mm.
Started out in daylight, because I don't have a good observing spot to look
at the moon when it starts to drop in the western sky. Had to catch it
while it was still high. During the sunset-early twilight period, I used an
orange filter to darken the sky background and make the details stand out
from the blue haze. This was the same #21 filter that we were all jonesing
for back around the time of the Mars opposition. It actually worked pretty
well, and I think I'll try this trick again.
Seeing started out 4 of 5, and never got much worse than about 3 of 5. Nice!
Mare Serenitatis was mostly illuminated, with a nice 'grayscale gradient'
across it. I always like that. The NE ramparts of the Montes Haemus were
catching the sun brightly.
The classic area of 'Imbrium Sculpture' was on the terminator tonight, at
the SW edge of Serenitatis. It had a very lineated appearance, particularly
in the area between Menelaus and Julius Caesar. This is a great region to
observe, given its significance in the recognition of large impact basins,
from the time of G.K. Gilbert all the way up through the time of Shoemaker.
The south polar area was reasonably well librated and lit tonight. I think
I identified Demonax and Scott clearly for the first time. Also Mutus,
Manzinus, and Schomberger.
I decided to try to go after some of Charles Wood's 'Lunar 100' targets
tonight. I suspect that I've already observed a fair percentage of them,
but this was my first attempt to bring the list with me to the eyepiece. I
started by picking out the crater Baco (L55), but its floor was mostly in
shadow. Wood's S&T article mentions that it has an anomalously smooth
floor, and that the surrounding plains are unusually flat. The floor was
mostly in shadow, but what I could see looked flat, I'd say. And the plains
around it did seem rather flat, which might be a bit unusual given how old
they presumably are.
L18 is the 'collar' of dark patches at the southern edge of Serenitatis.
This showed up nicely tonight. Saw a few parts of the Rimae Plinius, which
are associated with one of these dark patches.
Might have just caught part of the Bessel ray (L41), but I think it will
take slightly higher illumination to see it well.
In the north, Aristoteles and Eudoxus looked like bottomless black holes.
Nice complex E rim on Aristoteles. In this light it appeared to have a
'detached block' like the rim of Plato. Marvelous 'pebbly ejecta' in this
area, I could stare at it for hours.
Clefts and lineations on the rim of Julius Caesar suggest that it predates
the Imbrium sculpture. Cool age relationship!
Barely made out the circular form of Lamont (L53), a possible buried
crater. Wouldn't want the sun angle to be any higher. The domes Arago alpha
and beta showed up nicely (L32).
Rima Ariadeus - fat as a goose! (L29). An almost perfectly straight cleft
that transects numerous terrain features. Must have been due to some
late-stage stretching of the crust. Perfect illumination -- NE wall was in
shadow, while the SW rim was brightly lit.
At 20:55 PDT, I managed to FINALLY see the craters Armstrong, Aldrin, and
Collins. Psyched! He shoots, he scores! These are L90. I got to feeling
pretty sassy about bagging target #90. They had kicked my butt before, but
with very careful examination of Rukl, long sessions of staring through the
7Nag+2x barlow (429x), I managed to positively and repeatedly identify
them. That was really satisfying.
Hoped to see the Valentine dome, but it wasn't quite sunlit yet. Maybe next
lunation.
Finished up with more full-disc views in the 16Nag. Life was very good.
Marek Cichanski
Received on Sun Apr 25 23:29:39 2004