Crater Posidonius at Sunset
On this night I watched the sunset terminator creep slowly toward ring-plain crater
Posidonius; in addition I sketched the crater and other features on the floor of Mare Serenitatis. Posidonius (96 km.) is an old upper Imbrian era impact remnant. Its age is underlined by the way shadows penetrate the rim at numerous points betraying impact damage there. The highest part of the rim is on the terminator side of this crater. Sunlight was still reaching Posidonius A and other high points on ridges including one on the inner ring. Beyond this crater to the west and south the great serpentine ridge could be seen in best light. This ridge is made up of dorsa Smirnov and dorsa Lister.
Sketching:
For this sketch I used: black Strathmore 400 Artagain paper 9″x 12″, white and black Conte’ pastel pencils and a blending stump. After scanning, Brightness was decreased just slightly using my scanner.
Telescope: 10 inch f/ 5.7 Dobsonian and 6 mm eyepiece 241x
Date: 08-07-2012, 06:30 – 07:40 UT
Temperature: 29°C (85° F)
clear, calm
Seeing: Antoniadi III
Colongitude 147.9 °
Lunation 19 days
Illumination: 73.4 %
Frank McCabe
Frank,
Such wonderful details come to life in your sketch. I really like the serpentine ridge area and the starkness of the terminator. Always enjoy seeing your fine sketches posted here.
Warmest Aloha,
Cindy
Thank you Cindy,
It was a while back I made this sketch.
We had some fine late summer weather that year.
Frank 🙂
As Cindy said, we always enjoy looking at your sketches Frank.
And 2 years back it’s nothing for the moon.
Where did you find those interesting information about moon reliefs?
I have 3 moon atlas but when I have to find a crater history, I go to ASOD to find info if,…. you sketch already the area.
Thank you to share your work, superb sketch and interesting info
Michel
Spectacular sketch Frank. I like your renditions of scenery close to the terminator, when the slanting sun brings even low altitude features to prominence.
-Ivan
Michel and Ivan,
Thank you both for your kind words.
—- Michel, I believe I checked and use Christian Legrand’s Virtual Moon Atlas,
it is a free download.
Frank 🙂