After freshly recharging the battery which powers my mount, I was eager to try it out and also check out what was happening on Luna.
Experienced lunatics should get a laugh out of the next few paragraphs.
That Whacky Moon
The motions of Luna in the sky continue to surprise me, although I realize I shouldn't be surprised, because I understand it's motions pretty well from a theoretical point of view. But this theory doesn't translate into practice for me. I continually realize that I keep looking at the moon as a 'deep sky' object that moves quickly eastward day by day. This is a gross oversimplification, of course.
When I was looking at the younger moon, my sessions were quickly curtailed by deteriorating seeing as it set. In my mind, I thought, "Well, in a few days it will be significantly higher in the sky, because it will be significantly east of where it is now," just like any good deep-sky object would behave.
Well, that's half-right and half-wrong. At 10 days old, it is indeed signficantly further east than it was at 7.3 days old, but it wasn't signficantly higher. I realized it's following the ecliptic (more or less), not a parallel of celestial latitude (like all good deep-sky objects do), and the ecliptic descends in celestial latitude from Leo to Scorpius, and thus the moon gets lower as it moves east.
In spite of the disappointing elevation of the moon, it was showing lots of detail along the terminator.
Rima Hesiodus (Rukl 53, 54 and 63)
When I viewed at 119x (26mm ep) to get the lay of the land, I immediately noticed a thin gash extending E-W for a surprisingly long distance.
I quickly went to my highest power without a barlow, 413x (7.5mm ep). Things remained clear, and much more detail was visible. I tried 620x (2x barlow + 10mm ep), but there was a definite loss of detail, so I fell back to 413x, and used it for the rest of the session.
The gash turned out to be Rima Hesiodus, stretching across 3 Rukl charts all the way from the crater Hesiodus (54), going UNDER (apparently) Rupes Mercator (a 'rupes' is a scarp), continuing through the Marsh of Epidemics (Rukl 63, Palus Epidemiarum; Yuck! Truly this is the 'bad' side of the moon, no serenity or tranquility here!) finally arriving just north of Capuanus. Rukl shows a nice system of rilles just west of this, but the sun had not yet risen on this area.
Rima Hesiodus was pretty straight for the most part, and it was quite amazing that it continued on both sides of Rupes Mercator. Rukl shows it continuing over this feature, but I did not see this.
Bullialdus (Rukl 53)
Bullialdus was a glorious example of a deep lunar crater, lit by the low sun. It was half lit, and had beautifully detailed terraced walls. Surrounding the crater walls was a 'shield' or what I thought of as a hood of raised, disturbed, debris-filled land. The shadow of the eastern wall cut halfway across the crater, and it made a very nice design.
Pitatus (Rukl 54)
South and east of Bullialdus lay the walled plain Pitatus, which had a particularly prominent rille just inside the eastern wall and parallel to it, curving gently to the north west, maintaining a proper distance from the wall.
To the north, the Straight Wall (Rupes Recta) and Rima Birt were visible. Someone had commented that Rima Birt looked like a spermatazoa, and I have to concur, with Birt E being the head.
The Smiling Face of Wurzelbauer (Rukl 64)
Further south lay a smiling face in the midst of the old crater Wurzelbauer. The shading was just perfect, and it looked vaguely like a little tiny 'man in the moon'. There is almost no hint of this feature in Rukl, but I can see the mouth, nose and one eye on the chart. The nose is pointed NE, and is located slightly NW of 34S, 16W. The mouth exends from 34S, 16.8W to 34.5S, 16W. The eye is at 33.3S, 15.8W.
The Colorful Zach (Rukl 73)
Still moving south, the unusually colored crater Zach lay east of Clavius. There is an odd region of dark material in the NE corner. I am fairly certain this was not a shadow, but I expect to look at it again Sunday night. This dark feature, of which there's no hint at all in Rukl, abutted the NE interior wall. In the SE area of the crater, there was another, smaller, lighter colored dark spot, which was oval in shape, and stood out from the wall.
This caught my attention because the terrain in this area seems to be fairly uniformed light colored highland material. The presence of dark material made a strong contrast with the rest of the terrain.
Journey to Fra Mauro (Rukl 42)
I returned to Bullialdus, and then moved north along the terminator. I came across an unnamed interesting dome located at 11.5S, 26W. This feature was right on the terminator and it was very prominent. Only the peaks of the mountains just SW of it were brightly lit.
The floor of Mare Cognitum had lots of wavy, undulating patterns, some of them cris-crossing, south of Montes Riphaeus.
The Apollo 12 landing site in Mare Insularum was pretty flat and uninteresting. The Apollo 14 landing site was more interesting, being located in a slowly undulating landscape. I was really surprised at how close it was to the Apollo 12 site. They both were easily visible in the same 7' field of view at 413x.
I remember the television press reporting the Apollo 12 as the "Journey to the Ocean of Storms", and I was wondering why it wasn't called "Journey to the Sea of Isles", but Rukl reports this name was adopted in 1976.
Copernicus (Rukl 31)
Continuing north, I hit the famous crater Copernicus, one of the most prominent craters on the moon. Even at the low sun angle, some of the more prominent rays were visible, and I noticed sprays of lighter material splattered across the nearby maria.
Rima Gay-Lussac was obvious to the NW, a short, broad (for a rille) line, oriented sideways to Copernicus.
W, U, J, T, F, S, E, R, P Copernicus (Rukl 32)
About midway between Copernicus and Eratosthenes there is a very odd line of tiny craters forming a gentle curve vaguely parallel to the walls of Copernicus. This line starts at Stadius and heads NW. Unlike the chart in Rukl, the surrounding terrain appears very flat and featureless, thus causing the crater chain to stand out.
I finished the evening with a quick survey of Mare Imbrium, including Plato and the peculiar isolated mountains which rise mysteriously out of the mare along its northern edge.
It's really nice to use a battery that is fully charged!
--------------------------------------------------------------------- Date: July 3, 1998 10:30pm-12am (0530-0700 4 July UTC) Location: Backyard in Roseville (near Sacramento), CA 121W 16', 38N 44' Instrument: Intes MK-91 9" f/13.6 Maksutov-Cassegrain Oculars: 26mm, 7.5mm Sirius Ploessls Seeing: 8/10 somewhat wavy, but sharp Transparency: 7/10 hazy smoke from agricultural burning (blechhhh!) Age: 10 days Reference: "Atlas of the Moon," by Antonin Rukl (Kalmbach Books, 1996)