The Moon

1998 Mar 4


Another pretty good night, though the weather in San Jose CA was expected to be shaky to terrible. My luck is running.

Observations through C8 at 300x, with some later unnoted contemplation at about 165x.

Rukl Page 5

First on my list was the crater Baillaud, simply because I'd not noticed it before, and at first glance realized it looks tres cool. It's large, flat, and has a perfect "central crater" that caught the light in such a way as to have a pitch dark center and flaring rims. Kinda neat.

Rima Sheepshanks was uncharacteristically elusive tonight; I have found it easily in the past, and had to really work for it, only getting sections at a time. The seeing seemed good, so I guess this is a trick of the light at this libration and angle.

Aristotle(s) was simply amazing. The small crater chains and rills above it were blinking in and out, while the interior was only half lit. In this crossing light, the central peaklets and interior ruts were highly visible and extremely interesting.

Rukl Page 6

Unlike Rima Sheepshanks, Rima Gartner (in the semighost crater of the same name) was very easy. I don't recall noting this before, but it showed very easily in this light as a sinuous curving rille that gets fatter toward the north of the crater. This is one of those objects that gets more interesting with longer contemplation.

Rukl Page 13

The interior of Eudoxis was entirely obscured in shadow, but the intricate walls and surrounding mountainous terrain showed very well. There was also some evidence of the upper terracing inside... I've often seen it better, but it's always worth a glance.

The small but notable Rima Calippus was on and off in the seeing, but with some patience could be seen fairly thoroughly. Here, I'm not sure I agree with Rukl's drawing in that my own observation shows it going through a minor wrinkle ridge, where he shows it stopping short. I would be interested in hearing about other observations of this little gash.

Just to the east of the southern tip of the Caucasus was another phenomenal dome sighting, slightly past the bits of rubble on the interior edge of Mare Serenitatus. I know of no name for this dome, but as it was just on the edge of the terminator, it was perfectly lit and seemed much taller than it probably is. It seemed to have multiple "central" craters and possibly a few largish "boulderish" thingies on it as well; an odd duck of a dome for sure.

Serenitatis itself was dull by comparison with last night, and Poseidonius still showed well, but was disappointing after last night's wonderful apparition.

Rukl Page 23

Rima Sulpicius Gallus was in very odd illumination, just on the terminator. Usually it appears dark and distinct, but I was lucky enough to catch it when the light was reflecting precisely off one of the interior walls, making it a bright gash in the portions that run north south, transiting into a dark squiggle further south as it turns to the east. Some interesting detail was also visible in the roughly parallel foothills of the Montes Haemus; it looked almost as a study in light and dark, or as if there were more than one rille present.

The rest of Rimae Menelaus showed up for the party tonight; it's a particularly fine and tangled rille complex leading toward the crater Tacquet (which has a neat name so I had to mention it). In the moments of best seeing the area reminded me of cracked adobe soil.

Rukl Page 35

The northern sections of Rimae Maclear were much more easily seen than the southern stretches; for those I had to wait impatiently. But after a while, they showed themselves. But I have to admit part of the problem was the more distinct Rimae Sosigenes kept drawing my eye away: they are long long long and in my inadvertently averted vision they kept growing and growing... though they also appeared fainter to the south. And, of course, jabbing right at them was the amazingly black and obvious Ariadaeus Rille, a magnificent canal easily seen in just about any scope.

A bit further south, Rimae Ritter were very elusive. I only caught glimpses of some short stretches, which surprised me due to the ease with which the rest of the rilles around the rim of Tranquilitatis were spotted. The twin craters Sabine and Ritter showed a nice amount of interior detail of tiny craters and fractures, having just recently come into the full light.

Rukl Page 46

Continuing around the rim of Mare Tranqui (sounds like a latin drink) we come to the rest of Rima Hypatia. It wasn't as easy as it had been last night, but at least I could see the whole thing.

A little more than half way along a direct line from Theophilus to Delamore I spotted a curious little structure that looked more or less like a short rille, but have not been able to confirm it with any present charts. Another interesting tidbit similar to that presented itself to me in Kant D, a more or less flooded semighost ruined mess with a flat floor. Both general areas present a wealth of details and confusing terrain.

Rukl Page 57

If you have not yet pondered Catena Abulfeda (which I think I only spotted for the first time late last year) you should definitely try to keep track of this area. It's one of the best crater lines on the moon, and is all the more interesting for cutting through such rough terrain west of the remains of Catharina.

Also of note is the silly-named Sacrobosco, which is nicely shaped and has three nearly perfect medium craters inside.

Rukl Page 67

I found myself drawn to Stiborius tonight, as it was just coming into its own in the light, and had a very interesting interior structure, with mountains that seemed to almost form a chevron or "sergeant's strips." About half the interior is smooth and half structured, creating an interesting aesthetic.


Dave North; 1998 Mar 4