Mare Orientale

Session name: 20081015.2024
Equipment: Takahashi FS-102 refractor
Location: Drip Rock
Conditions: Scattered clouds, clear by Moon and calm air, mild temperature in the 60s.
Seeing: AII - AIII
Transparency: Decent
Traffic flow: very low (qty - 5)

Photo caption: Pete Lawrence's images of Mare Orientale on iPhone from Central Park

I was encouraged for this session after discovering the Pete Lawrence photos of Mare Orientale via a circuitous route in the lunar-observing yahoo group. In fact, I used the image to properly identify the features I could see in the eyepiece even if it was a day's difference. Later, a passerby stopped when I was packing. We chatted and he asked some questions about the moon. To show him what I was observing I whipped out the iPhone to display the very feature I scrutinized.

The concurrence of favorable libration, a proper phase, clear weather, and a reasonable hour is not too common. In my observing career, I only have a few observations of Mare Orientale, this one not the best. At the beginning of the session while the scope cooled down, there was some boiling seen along the limb. As the Moon climbed higher and the scope cooled down and the moments of steady seeing increased, the observation offered more detail.

East of Lacus Autumni, I observed two peaks on the limb. The outer one (north/Montes Cordillera?) was more prominent and a sharper shape compared with the nearby inner peak (Montes Rook?). For the inner peak, the side closest the northern peak appeared to have a gradual rise from behind the ridge of Montes Cordillera and at the peak a small indent or cleft was observed which then the wall fell sharply. What appeared to start from the outer peak, a ridge ran parallel inside of the moon limb for good length, about ~2 1/4 ~ 2 1/2 Lacus Autumni-lengths. This ridge was interrupted by the crater Eischstadt. The ridge I suspect was Montes Cordillera. Further south along the limb, I saw two small humps that I assumed were the corresponding peaks of the pair north. My notes describe these as undulations and not as pronounced as the pair above. Contrasting with the northern pair, the inner peak of the southern pair has the sharper, peaked figure.

What did the Moon like this evening? Check astromick's shots

Passersby and the Moon

I never consider observing the Moon old hat. Some pedestrians remark with disdain, "Only the Moon." after I answer their original question of what am I looking at with the telescope. Regardless, I offer them some eyepiece time to observe the Moon at magnification 63x or 91x, whichever is available at the time. Their expressions belie their disinterest, they marvel at craters and dramatic landscapes skirting the terminator. If the opportunity avails, I swap out the eyepiece for a lower magnification where the entire Moon appears suspended in thin, black air. Many thank me, many shake my hand. The Moon has shook them.

Autumn Sights

It's Autumn and migration season for the birds flying south. All night long with regular frequency, we could see birds crossing the face of the Moon when looking in the telescope. Most would flutter across, wings beating, tiny compared to the disk of the Moon in the field of view. It appeared to be random trajectories, but watching them fly by most ingressed from the terminator side, corresponding roughly to a north - south direction. I asked some of the folks about how birds might use the Moon for migration and navigation but no one really knew.

Schiller-Zucchius Basin

Session name: 20081010.1900
Equipment: Teleport 10" Reflector
Location: Top of the Lawn
Conditions: Clear night and calm air, mild temperature in the 60s but okay for t-shirt.
Traffic flow: ---
Objects observed: Moon, Jupiter, Callisto transit, Neptune, Albireo, Double Cluster, M31/32, M51.

Photo Caption: Mark up of LO4-154H3; a filtered image sourced from Charles Byrne [1]
Here or photo for larger version of mark up or larger clean, unmarked image.
The original LO4-154H3

The intent of this session was to continue to watch the lunation unfold towards Full Moon from previous sessions over past few days. The waxing gibbous Moon was ~11 days 15 hours with favorable libration for the southern polar region. Mare Australe was apparent on the SE limb and Newton was entirely visible inside the horn of the terminator's crescent.

Three conspicuous craters of apparent equal size sit within the terminator in the south southwest: Zucchius, Bettinus, and Kircher. A fourth one, Segner, abuts Zucchius to the north but appears more shallow and slightly more elongated. I've seen these craters many times before but never noticed the arcuate ridges that stretch between Schiller and Segner.

Two scarps are apparent, not as strongly as those of Mare Nectaris, but nonetheless obvious once they are detected. The outer ring wall arcs from Schiller past the intersection of craters Rost and Rost A, past crater Weigel up to Zucchius-Segner meet point. The inner ring can be seen as an arc from Schiller inside of Weigel and stopped by Segner.

[1] Byrne, Charles J. Lunar Orbiter Photographic Atlas of the Near Side of the Moon. Springer-Verlag. 2005.

Observing Log refresh

Session name: 20081004.0900


I begin my sixth year of observing from the Great Lawn, first at TPO, now at TotL, with a fresh logbook - a black 3.5" x 5.5" Moleskine plain 192 page notebook that fits easily in my pocket. This is number 11 since adopting this notebook as my standard. I've used others like the larger 5.25" x 8.25" Moleskine journal with 240 blank pages and a landscape format called the Reporter and quadrille-ruled in both large and pocket sizes. I prefer the blank page. They're not filled entirely with field notes but include other offline notes. The first notebook that I began to collect notes in was a Barnes & Noble quadrille ruled notebook, There are some random observation notes as early as 2002.

I'm in agreement with many others that a log is book is important to help shape your observing program, improve your observing skill, and crutch the memory. Usually I review, analyze and evaluate recent notes to develop a game plan for the next session. I look back on older notes & sketches with the same enjoyment as I do looking at developed snapshots.

One project I have never got fully underway was to database my observations. Dave p. & Jeff Burton have very impressive databases that integrate well with the websites. I've compiled some lists in Excel spreadsheets but never got all the data into a database. Seems like a daunting task that I won't do in the near future.