Category: Basin

Gassendi, Rimae Mersenius and Rupes Liebig at the terminator

Mare Humorum including Gassendi, Rimae Mersenius and Rupes Liebig at the terminator - December 2, 2014
Mare Humorum including Gassendi, Rimae Mersenius and Rupes Liebig at the terminator – December 2, 2014
Gassendi, Rimae Mersenius and Rupes Liebig at the terminator labeled
Gassendi, Rimae Mersenius and Rupes Liebig at the terminator labeled

Aloha!

This was one of those nights things just fall together. Excellent seeing and light enough from the Moon that I could see the paper well. After finishing my sketch at the eyepiece I went inside to clean it up and was pleasantly surprised that I liked it pretty much the way it was.

110km wide Gassendi Crater showed some excellent roughened floor details with hummocks casting shadows as well as floor rilles illuminated as bright & dark lines. Rima Mersenius is brilliantly lit on the terminator and the bright scarp of Rupes Liebig can be seen at the base of the wall.

Gassendi Crater, Mersenius Rille, Rupes Liebig, Mare Humorum @11.7 days lunation
.12/2/14 2030-2140 HST
12.5″ Portaball, 227x
Canson Black paper and white and black Conte’ Crayon, white charcoal pencil
Photoscape to adjust contrast

Cindy (Thia) Krach
Haleakala Amateur Astronomers
Maui, Hawaii

Gassendi at Terminator

Lunar crater Gassendi - October 4, 2014
Lunar crater Gassendi – October 4, 2014

Object Name: Gassendi
Object Type: Lunar Crater
Location: Dunboyne Ireland
Date: 4th October 2014
Media: Graphite pencil H2, H3 & B6 with standard white stock and technical drawing equipment.

This is actually sketched as observed through the eyepiece with a 15mm on a 9.25 SCT rather than from the phone screen. The seeing was fair but a weather front was fast approaching and just managed to observe long enough to capture this detail. At the same time I took some snapshots through the eyepiece with my smartphone for a smartphone astronomy site – so got to do both before the clouds rolled in. Adding the phone to the sketch allows me to add a technical drawing into the mix which I not (only) enjoy but also allows me to capture the evenings activities and optical equipment used during the session.

Many Thanks

Kevin

Crater Gassendi and the northern part of Mare Humorum

Lunar crater Gassendi and the the northern part of Mare Humorum - September 5, 2014
Lunar crater Gassendi and the the northern part of Mare Humorum – September 5, 2014

Here is a sketch of the Moon on the 5th of September from my backyard
in Adelaide, South Australia.

The moons phase was waxing at 83%, with only the very western edge
still in shadow. I observed with a C11 SCT. Seeing was quite
reasonable, so I took a 15mm eyepiece + 2x Barlow for a close look.

The shallow illumination on Mare Humorum made the creases on the mare
floor stand out. Crater Gassendi, toward the bottom, showed stark
shadows. Rimae Hippalus was visible, passing through the partially
submerged crater Hippalus at the top right. Because I used a diagonal
prism, the sketch is mirror imaged.

I used pastel chalks and black and white pastel pencils on black
paper.

-Ivan

Sunrise at Rainbow Bay

Object Name Sinus Iridium
Object Type Lava plain on the Moon
Location Deventer, the Netherlands
Date April 13, 2011
Media White pastel on black paper

I have made a pastel sketch of one of the features on the Moon which beauty always strikes me whenever it’s visible: Sinus Iridium (Bay of Rainbows). It is a very large feature and always looks very nice in even the smallest telescopes. On that evening of April 13 the Sun’s angle was just right to give the surface that gradient view: dark near Montes Jura with a gradual brightening towards the west. A few rilles were also visible. It was a very pretty sight through my 300mm f/4 truss Dob using a 5mm HR Planetary eyepiece (240x). The sky was a bit hazy while I made the sketch, but the seeing was great.

Kind regards,

Roel Weijenberg
www.roelblog.nl

A Partial Nectaris Basin Ring

On a beautiful spring evening with mostly clear, warm skies, I was able to sketch the famous fourth ring of the Nectaris basin, namely, the Altai scarp or Rupes Altai. Sunlight was bouncing off the outermost visible rim of this combination basin ring / fault enhancing its visibility north of impressive crater Piccolomini (88 km.) and beyond for 500 kilometers. Some of the sheer cliffs are 3.5 – 4 km.high and are nicely treated and described in Steve Bounce’s interesting study and profile in Selenology Today #10, June 2008.
What was also eye catching about this view was the fine illumination and shadow on the terraces of crater Piccolomini. The 2 km. tall central peaks of this crater above its smooth floor added to the grandeur of the eyepiece view.

Sketching Information:

Sketched on white paper using graphite pencils (HB, 4B, 6B), blending stumps, white Pearl erasers
10” f/ 5.7 Newtonian riding on an equatorial platform and a 6mm eyepiece for 241x
Date and Time: April 10, 2011, 01:50-02:40 UT
Weather: partly, calm, 65 degrees F (18 degrees C)
Seeing: Antoniadi II-III
Lunation: 6.4 days
Moon 34.8% illuminated

Frank McCabe

Sunset Terminator Across Mare Crisium

Mare Crisium is that interesting isolated sea on the northeastern side of the visible lunar surface. Only about half of it was visible during this sketching session.
The Nectarian Period event that formed this feature occurred more than 3.8 billion years ago. The mare portion of the basin is about 500 kilometers across. In the grazing sunlight across the floor, wrinkled ridges were visible in the north to south direction. Also on the western floor craters Picard (24 km.), Peirce (19 km.) and Swift (11km.) stood out in the low light. I could clearly see the lighter colored bench lava that partly buried craters here such as Yerkes (37 km.). Tall flat top mountains (massifs) beyond the shore stand at 2-5 kilometers above the sea. Also beyond the sea to the West crater Proclus (28 km.) with its remarkable bright rays was reflecting some sunlight.

Sketching:

For this sketch I used: 400 series black Strathmore Artagain paper 9″x 12″, white and black Conte’
pastel pencils , and Conte’crayons, a blending stump, plastic eraser. Brightness was decreased -2 and contrast increased +1 using the scanner for this sketch
Telescope: 10 inch f/ 5.7 Dobsonian with 6mm (241x)
Date: 12-23-2010 10:00 – 11:30 UT
Temperature: -8°C (18°F)
Weather: clear, calm
Seeing: Antoniadi III
Co longitude: 120°
Lunation: 17.7 days
Illumination: 94.5%

Oak Forest, Illinois

Frank McCabe

The Multi-Ringed Crisium Basin

Staring down the telescope eyepiece last night, I saw the terminator crossing Mare Crisium in such a way that all the main basin rings were visible. That only left the challenge of illustrating them in a sketch; not an easy thing when you consider the breadth of lunar landscape they cover and the amount of detail they include. So: from inner to outer here they are – can you spot them all?

1. The inner wrinkle ridge just inside and parallel to the Mare border (Dorsum Oppel).

2. The mountainous terrain of the mare border itself.

3. The Cleomedes ring. Cleomedes is the large terraced crater to the north of the Mare and partially in shadow. You can identify the high ground surrounding it by virtue of the low ground either side. To the south of the Mare this low ground is also visible in amongst the more jagged mountains.

4. The Geminus ring. Geminus is the large crater at the top of the drawing totally in shadow. A ring of slightly higher ground arcs right round the north of the mare, with a gap to the west, then rejoins as the mountains to the Mare’s south.

The multiple rings of Crisium are quite obvious once you know they are there, so it’s amazing how it took the Lunar Orbiter images of Mare Orientale to really focus the hunt for similar features on the lunar near-side. I drew this in about 40 minutes, finishing it quickly mainly because I was cold and tired. But I also find that forcing myself to sketch fast helps me to focus on observing the main features first and getting them down on paper.

Object name: Mare Crisium

Object type: lunar mare basin

Location: York, UK

Date: 23rd November 2010

Medium: graphite pencil on white paper.

Instrument: Skywatcher skyliner 152mm f8 Dobsonian, 10mm e.p.

Peter Mayhew

Gibbous Moon With Sinus Iridum Detail

Gibbous Moon
Moon – Gibbous With Sinus Iridum Detail
By Mark Seibold

Technical Information regarding sketch:

A 19″ X 25″ pastel sketch [with the moons disc drawn at 12 ¾”] on black Strathmore Artagain pastel paper with use of various soft to hard pastel chalks on December 26th 2009 at 5UT ~ 9UT, partly produced from direct eyepiece observation over 2 to 3 hours, then finished indoors with photos taken from the eyepiece to produce a detailed close-up of the Sinus Iridum feature at the terminator. An artists conception was added at bottom as a final touch for a total work time of 4 ~ 5 hours. Observation was through my 10.1 inch f/4.5 Newtonian telescope with use of 32mm, 12mm, 9.7mm Super Plossls and 6mm Orthoscopic eyepieces. Ambient outdoor temperature in the 750 ft elevation foothills, west of the Cascades and Mount Hood, 30 miles east of Portland Oregon was approximately 34 degrees F. Wind gusting to 20 ~ 30 mph and subsiding to still at times.

*A slightly higher quality image may be viewed at
http://i10.photobucket.com/albums/a109/markseibold/Moon_PastelGibbous6_SinusIr.jpg.

Sinus Iridium Ejecta and Beyond

Sinus Iridium Ejecta and Beyond

Lunar craters Mairan, Sharp, Harpalus and the Jura Mountains
Sketch and Details by Frank McCabe

The lunar feature known as the Jura Mountains includes the rim of the Sinus Iridium impact and is visible here in late day sunlight. The debris field can be seen extending westward to Mare Frigoris. All of Sinus Iridium is in shadow which gives this region an unfamiliar appearance. The impact that created the large mountainous debris field occurred during the Upper Imbrium period (3.8 billion years ago). Some of the mountains are a lofty 5 kilometers high. Superimposed on these mountains are two forty kilometer complex craters known as Mairan and Sharp; another similar sized crater can be seen on Mare Frigoris and is called Harpalus (39 km.). At high sun this crater shows a bright young crater ray system in addition to a fine glacis. There are 3 pillow-like features to the far left in the sketch at the edge of the Iridium ejecta. The two that are closest together are the famous large lunar domes known as Gruithuisen Gamma and Delta.
It is always worth while when not expecting a rigorous day ahead to get up a little earlier than usual to see what is going on in the sky before sunrise. This is especially true when the sky is clear and very transparent.

Sketching:

For this sketch I used: black Canson paper 9″x 12″, white and black Conte’
pastel pencils , and Conte’crayons, a blending stump, plastic and gum erasers. Brightness was decreased -2 using the scanner for this sketch
Telescope: 10 inch f/ 5.7 Dobsonian with 9mm (161x) eyepiece
Date: 11-12-2009 11:00-12:00 UT
Temperature: -3°C (27°F)
Clear to partly cloudy, calm
Seeing: Antoniadi III
Co longitude 212.7°
Lunation days 25.27
Illumination 20.1%

Frank McCabe