April 13, 2011: Longer Lunar Session, halfway through Lunar 100!!

[michael.h.f.wilkinson]

Yesterday I let the scope cool under slightly hazy skies, with some thin cloud hovering about. At about 9 PM I went outside, set up the scope, and started hunting lunar features.

I started out on some nice big items such as Sinus Iridium and Copernicus, both beautifully lit, before going for some unfinisched business from two days ago.

I got the Davy Crater Chain (L51), this time round, although the lighting was not ideal. Still a string of little craters stood out, running from Davy towards the lower part of Ptolemaeus. I tried both 203x with the Radian 10, and 254x with the Radian 8, but the former was actually better.

Next up were the Mare Serenitatis dark edges (L18). These were quite prominent at the southern edge of the mare, even in the 22mm Nagler.

Sticking to dark matter , The Alphonsus dark areas (L47) on the crater floor were easily picked out at 254x with the Radian 8.

Another "dark" feature is tiny Copernicus H (L74) at least compared to mighty Copernicus. It is a neat little crater, spotted at 203 and 254x quite readily, and has a curious dark halo around it.

Sinus Aestium (L79) is just to the left of Copernicus in my view (remember I am using a star diagonal), and also has a c-shaped area of darker material showing.

North of Copernicus, near Pytheas, a string of secondary craterlets (L69) shows, at 254x, often embedded in rays of ejecta. Really neat sight.

At this point the weather was clearing up rapidly, and I took a chance at getting the Plato craterlets (L83). At 254x the largest (in the centre) winked at me through varying seeing, and hints of at least two more showed. I barlowed my Radian 10 with a Meade 2x TeleXtender, to reach 406x , and I was impressed by the view. Luna pumps out enough photons to keep the image crisp. The three largest craterlets were clearer now, and one or two others seemed to pop in and out of view. I moved over to Sinus Iridium for a high-res look and I was stunned at the detail. I switched back to 254x and could see much the same, but the 406x held up nicely.

Moving back towards Copernicus, The Hortensius domes (L65) were well visible just to the north of the crater of the same name, and south of some steeper mountainous structures.

I went south of Copernicus to spot the Fra Mauro Formation (L67), on the northern edge of the crater Fra Mauro. Under the fairly oblique lighting the walls of the formation stood out nicely.

Switching north again I first tried L49, Gruithuisen Delta & Gamma, but they were just in the dark. Instead, I tried for the Hadley Rille (L66), which shows up as a sinuous rille alongside a crater, in a bay in the north end of the Apennines. Difficult at 254, a bit easier at 406x.

Moving back to the centre of Mare Imbrium, I located the north-west wall of Lambert R (L78), the rest of it flickered in and out of sight (254x was better than 406x in this case). I must visit this again to see it more clearly.

I tried for the Mare Imbrium lava flow boundaries (L98) in the same region, but further north. Though I readily spotted several sinuous ridge structures running across the region, and more-or-less linear discoloration on the floor of the mare, I am not sure I got this, as I have not found any good photographs of the feature yet. A pointer to what I should see is most welcome.

Hesodius A (L81) and Pitatus (L84) lie side by side at the south of Mare Nubium. Hesodius A is a little impact crater inside Hesodius, exactly where you would expect a central uplift. Quite curious. Pitatus has rilles running along the inside of the crater walls. Readily spotted at 254x.

Finally I moved to Kies Pi (L60), which was also illuminated favourably. It shows up as a flattened dome, almost like an archetypal shield volcano right and south of Kies. It should not be confused with the larger mountain a bit further away in the same direction.

At that point, I hit 50 out of the Lunar 100, and the missus came home from a meeting, so I called it a day (or night), but not after gunning for Saturn, which showed up neatly at 254x, with three moons (Titan and two others I must still identify). I tried 406x but that was too much, and showed up atmospheric refraction. At 254x the Cassini division stood out quite well, as did the banding on the planet.

A great evening with a nice landmark reached! Thirteen new L100 features and one possible, plus a few old friends is neat. If anyone can give me pointers as to L98, that would be much appreciated.

[Doc]

Congratulations a lovely report.

This is what I said about Number 98 and also the photo that I used to confirm.

Top craters are Helicon and Le Verrier and bottom one is Lambert and one half way on the right is Callini D.

Number 98 Imbrium lava flows

I was not dead sure where these lava flows were but I scanned every inch of Mare Imbrium and found some raised plains, similar to white lines that lie between crater Lambert and le Verrier. I could also detect a slight one touching crater Carlini D.

[michael.h.f.wilkinson]

Congratulations a lovely report.

This is what I said about Number 98 and also the photo that I used to confirm.

Top craters are Helicon and Le Verrier and bottom one is Lambert and one half way on the right is Callini D.

Number 98 Imbrium lava flows

I was not dead sure where these lava flows were but I scanned every inch of Mare Imbrium and found some raised plains, similar to white lines that lie between crater Lambert and le Verrier. I could also detect a slight one touching crater Carlini D.

Thanks for that! I am not sure I spotted these, I will have to check when the lighting is more favourable.

Cheers

Michael

[Doc]

I found it very hard as well, the lighting has to be just right. I definetly spotted number 3 the one by Callini D and I saw a few white streaks running down Mare Imbrium similar to nunbers 2 and 4 but they were very dim.

best of luck.

[m_j_lyons]

Great report - my L100 quest came to a halt with the Pacific jet stream that has several weather systems rolling though my area...if I were a cloud observer things would be great. Forecast is for about 5 more days of clouds then a clearing trend. Anyway - glad to hear that you're making good progress - do you maintain photos or just a log?

[michael.h.f.wilkinson]

Great report - my L100 quest came to a halt with the Pacific jet stream that has several weather systems rolling though my area...if I were a cloud observer things would be great. Forecast is for about 5 more days of clouds then a clearing trend. Anyway - glad to hear that you're making good progress - do you maintain photos or just a log?

Just a log, I have done a few lunar photos, but I am usually content with logging the finds