Moon – Page 49 – Astronomy Sketch of the Day

The Asperity South of the Bay of Asperity

Catharina, Cyrillus and Theophilus
Sketch and Details by Frank McCabe

If you have not observed this trio through a telescope then you are in for a treat when you do. The trio I speak of is Catharina, Cyrillus and Theophilus. All three of these craters are between 100 and 104 kilometers in diameter. The oldest of the three is Catharina which is also the southern most of the group in this north at the bottom sketch. Catharina, a Nectarian period impact may be older than the Imbrium basin with debris from that basin scattered across this crater and the older surroundings. Cyrillus a bit younger than the former shows terraced walls and worn central peaks. The last member of the trio is one of those lunar treats that cannot go unnoticed. Theophilus, an Eratosthenian crater, just about has it all. It is large, sharp rimmed, terraced walled, tall central peaks (2 km.), a flat floor, and much melted ejecta just beyond the crater especially to the north and east. The outer reaches of Theophilus gradually merge with the Bay of Asperity.

To the east 28 km Mädler can be seen disappearing into the shadows approaching from the left as they cross the Sea of Nectaris.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, white and black Conte’ pastel pencils, Conte’ crayons and a blending stump. After scanning, Brightness was slightly decreased (-2) and contrast increased (+4) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 9 mm eyepiece 161x

Date: 6-23-2008, 7:30-8:50 UT

Temperature: 15° C (59° F)

Clear, transparent, calm

Seeing: Antoniadi II

Colongitude 147.9 °

Lunation 19.5days

Illumination 81 %

Frank McCabe

Once a Prominent Giant

Jansen and his neighbourhood
Sketch by Bognar Tamas, Details by Richard Handy

Janssen’s rugged and crater battered walls are rendered with wonderful precision in this sketch by Bognár Tamás of Zakany, Hungary. Janssen, a large 190 km crater originally formed during the the Pre-Nectarian age, would have sported a complex series of terraces and obvious set of central peaks, at least initially. Subsequent bombardment by meteorites of all sizes have reduced this once prominent giant into a bare hint of it’s former majesty.

Jansen and his neighbourhood
Telescope: 3″ F/11 Newton and 7,5 mm Super Plossl eyepiece
Date: 02-11-2008 UT 15:50-16:50
Co-longitude: 330,1°
Observing Location: Zakany – Hungary, 46° 15′ N 16° 57’E elev.: 129m

Thank you for it!

—
Üdvözlettel !
Bognár Tamás

2008. június 14.

Eddington: A Mere Shadow of its Former Self

Eddington
Sketch and Details by Frank McCabe

I was disappointed with my previous observation of this region of the Ocean of Storms this past August and this night was my first opportunity to return to this area. On this evening of observing and sketching, 137 kilometer, walled-plain crater remnant Eddington was well positioned and illuminated in the morning sunlight for drawing. The features that identify Eddington as a large crater ruin include the missing southern and eastern rims and the vast flooding of its floor with the mare lavas. Eddington is a Pre-Nectarian period crater which is likely older than 4 billion years. Today its worn appearance still has character. There is a broken arc of rim remains from south to east which gradually climbs from hills to mountains as the rim arc is traced northward. It may no longer be a regal crater, but it makes an excellent bay to the shore of the Ocean of Storms. To the east-southeast of Eddington rests the much younger Eratosthenian period crater Seleucus (44 km.). This is a deep crater at 3 km. and has a bright meandering debris ray from the crater Oblers A (not seen) passing the crater to the east. The Soviet moon probe Luna 13 landed 75 kilometers southeast of this crater. South along the terminator is the crater Krafft (51 km.) which makes an interesting partner to crater Cardanus beyond the sketching region to the south. Two craters are visible north and east of Eddington. These craters are Briggs (37 km.) and Briggs B (25 km.). Both were showing dazzling rims and ramparts in the early sunlight. The lone crater visible across the sketch to the northeast is Imbrian period crater Schiaparelli at 24 kilometers in diameter. This was that perfect lighting I was waiting for to capture this little corner of the Ocean of Storms.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, white and black Conte’

pastel pencils and a blending stump. After scanning, Brightness was slightly decreased (-3) and contrast increased (+3) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 9 mm eyepiece 161x

Date: 6-17-2008, 2:55-3:50 UT

Temperature: 19° C (67° F)

Clear, transparent, calm

Seeing: Antoniadi III

Colongitude 72.7 °

Lunation 13.4 days

Illumination 98 %

Frank McCabe

Rainbow Bay

Sinus Iridum
Sketch and Details by Frank McCabe

Sinus Iridum (Bay of Rainbows) is one of the more attractive impact regions of the lunar moonscape under grazing illumination. The northern and western rim of this impact basin is composed of the rugged Jura mountain range from Cape LaPlace in the northeast to Cape Heraclides (the Moon Maiden) to the west. The bay reaches across a central distance of 260 kilometers. The entire southern portion of the crater rim is not seen for it is covered by the Mare Imbrium lava flows. First the massive impact that created Mare Imbrium about 3.8 billion years ago occurred. That event was followed by the smaller basin creating impact that left the large “crater Iridium” and subsequent events that buried its southern rim under lava flows some 3.3 billion years ago. Some geologists have suggested a seismic event before the lava flows aided in lowering the southern rim (see C.A Wood, The Modern Moon, p. 37).

One of the first sketches featuring Sinus Iridium in a telescopic view was done by Giovanni Cassini in 1679. In his drawing the Moon Maiden is featured. In my drawing Promontorium Heraclides (Moon Maiden) is seen at the upper right. Beyond this cape is a frozen wave of lava known as Dorsum Hein at the top center of the sketch. Following the arc of the sunlit Jura range, your eye arrives at the large shadowed floor of crater Bianchini (39km.) just beyond the half way point to Promontorium LaPlace (Cape LaPlace). Note the slumping of rim debris out into the bay from crater Bianchini. On to Cape LaPlace there is a tall mastiff at the cape that is casting a large triangular shadow that created a pleasing and eye catching view at the telescope ocular. Out beyond the reaches of the Bay of Rainbows are a pair of 20 km. diameter craters; Le Verrier is the slightly smaller one on the left and the other one is Helicon. This is a fascinating region of the moon to explore with a telescope and great fun to try and capture on paper.

Sketching

For this sketch I used: White CPP sketching paper, 9”x 12”, Numbers 2H, B and 4B graphite pencils, a blending stump, plastic eraser and an eraser shield. After scanning, Brightness was slightly decreased (-3) and contrast increased (+3) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 9mm eyepiece 161x
Date: 6-14-2008 1:30 – 2:42 UT
Temperature: 24° C (77° F)
clear, breezy
Seeing: Antoniadi IV
Co-longitude: 34.9°
Lunation: 10.26 days
Illumination: 81.5 %
Phase: 50.9°
Observing Location: +41°37′ +87° 47′

Frank McCabe

A Rima Runs Through It

Rimae Agrippa
Sketch by Bognár Tamás

This beautiful sketch of Rima Ariadaeus was sent in by Bognár Tamás of Zakany Hungary. This rille, one of the most dramatic on the Moon, runs for a length of over 200 kilometers, cutting through hills and crater walls before vanishing into Mare Tranquillitatis.

Rimae Agrippa
Telescope: 3″ F/11 Newton and 7,5 mm Super Plossl eyepiece
Date: 02-13-2008 16:10 – 17:30 UT
Co-longitude: 354,5°
Observing Location: Zakany – Hungary, 46° 15′ N 16° 57’E elev.: 129m

A Triplet of Craters in the Southern Highlands

Craters Cuvier, Heraclitus, and Licetus
Sketch and Details by Frank McCabe

It has been a long time since I have attempted to use charcoal pencils on white sketching paper but I found an unused pair among my drawing supplies. They turned out to be less messy than ones I have used in the past. I liked the way they worked on the medium weight drawing paper I had on hand.

Two years ago in March of 2006 the European Space Agency (ESA) spacecraft Smart-1 imaged the crater Cuvier to test the high resolution camera (AMIE) with great success. I noted this crater was well placed along the terminator last evening for sketching. No sooner than having seen it, I decided it would be my target for sketching. Cuvier a 77km walled-plain crater is eastern most in the sketch. The crater has a nearly flat, lava flooded floor and at 3.5 billion years old is still younger than its neighbor to the southwest Heraclitus. Elongated crater Heraclitus is from the Pre-Imbrian period and dates back more than 4 billion years. A central mountain ridge runs down the center of this crater from northeast to southwest. This ridge line was illuminated in the morning sunlight. Within the shadow of this crater 25% of the dark southwest floor is occupied by Heraclitus D. Finally the large 74 km. crater to the northwest is Pre-nectarian crater Licetus. It like Cuvier infringes upon Heraclitus.

It was a beautiful night to observe and sketch the moon.

Sketching:

For this sketch I used: White CPP sketching paper, 9”x 12”, Number 4B charcoal pencils, a blending stump, gum eraser and an eraser shield. After scanning, Brightness was slightly decreased (-2) and contrast increased (+2) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 6mm eyepiece 241x
Date: 6-11-2008 1:05 – 2:05 UT
Temperature: 24° C (76° F)
clear, calm
Seeing: Antoniadi III
Co-longitude: 358.9°
Lunation: 7.29 days
Illumination: 55.1 %
Phase: 84.1°
Observing Location: +41°37′ +87° 47′

Frank McCabe

Upon the Sea of Clouds

Bullialdus Crater
Sketch and Details by Frank McCabe

Western Mare Nubium has been the home of complex, Eratosthenian period crater Bullialdus (61 km.) for the past three and a half billion years. The beautifully terraced inner walls to the east and kilometer high central peaks were clearly seen in the morning light. The outer downward sloping walls were showing alternating radial ridges and valleys down to the lava flooded floor of Nubium. The crater rim stands 2.4 kilometers above the crater floor and the floor is 1.2 kilometers below the surrounding Mare Nubium lava.
The ancient flow of lava across the Sea of Clouds breached the walls and flooded the floors of craters Kies (44 km.) to the southeast and Lubiniezky (44 km.) to the northwest of Bullialdus. Immediately to the south of Bullialdus are Bullialdus A and B, both twenty something kilometers in diameter with the closer A being the larger of the two. The famous 11 kilometer dome Kies л was clearly seen just to the west of crater Kies and to the northwest, crater König (23 km.) looked impressive with its dark shaded floor.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, 9”x 12”, white and black Conte’pastel pencils and a blending stump. Brightness was slightly decreased (-3) and contrast increased (+2) after scanning using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 6mm eyepiece 241x
Date: 5-15-2008 2:10 – 3:45 UT
Temperature: 8° C (46° F)
passing clouds, calm
Seeing: Antoniadi III
Co-longitude: 28.8°
Lunation: 9.6 days
Illumination: 78.5 %
Phase: 55.3°
Observing Location: +41°37′ +87° 47′

Frank McCabe

Raising Eyebrows on the Floor of Imbrium

Aristillus and Autolycus
Sketch and Details by Richard Handy

Sitting replendently on the the eastern margin of Mare Imbrium, 56 km Aristillus and 41 km Autolycus, brothers of Copernician age, are a startling sight in the late lunar afternoon sunshine. Hexagonal in appearance, Aristillus’s broad and radially splayed glacis dominates the mare surface in this region. It’s wide, brilliantly lit terraces apparently have evidenced some mass wasting since its creation a little over a billion years ago. Resting on the floor, some 3650 m deep, the glowing central peaks are roughly 900 meters high. Rays, some quite prominent, emanate from the crater’s center. To the northwest of Aristillus, swathes of darker mare may indicate areas not fully dusted by the ejecta from this massive impact, or perhaps ejecta excavated from deep within the extant mare is responsible for these low albedo areas. Approximately 60 km to the south, Autolycus’s glacial nimbus appears almost serene in comparison to the complex nature of Aristillus’s glacis. Half of the floor of Autolycus is composed of quite torturous terrane including a strange floor subsidence to the eastern section of the floor.

Here are the sketch details:

Subject: Aristillus and Autolycus Rukl: 12
Date: 10-13-06 Start: 9:15 UT End: 10:50 UT
Lunation: 20.90 days Phase: 277.5 deg Illumination: 56.5%
Colongitude: 164.8 deg Lib. in Lat.: -5 deg 40 min Lib. in Long.: +7 deg 39 min
Seeing: Antoniadi III-IV with 30 seconds of Ant. II every 20 minutes
Weather: Clear early, turning to occasional clouds mid to late during session, 10-15 knot winds late.
Telescope: 12″ Meade SCT F10
Binoviewer: W.O. Bino-P with 1.6X Nosepiece.
Eyepieces: W.O. WA 20mm Plossls
Magnification: 244X
Lunation: 18.48 days Phase: 311.1 deg Illumination: 82.9%
Colongitude: 133.7 deg Lib in Lat.: -3 deg 53 min Lib in Long.: +5 deg 12 min
Sketch medium: White and black Conte’ Crayons on black textured Strathmore paper.
Sketch size: 18″ x 24″

Morning at Crater Walther

Walther Crater
Sketch and Details by Frank McCabe

On this spring evening I drove over to our local community college to pick up and bring home the observatory telescope which was in need of cleaning and minor repairs. When I finished that work the sky was clear so I decided to use the scope to make a lunar sketch. The target I selected for drawing was the large (140 km.) Nectarian period walled plain crater Walther. On older lunar atlases this crater is either labeled Walter or Valtherus but in 1982 the name was changed to the current Walther by the IAU. I have always found the moon shows off some of its best large craters at this time in the lunation. Walther is one of those great old highland craters with much to offer a careful observer. Most seasoned lunar observers are well aware of the Walther sunset ray, but even at sunrise this crater has its rewards. A combination of craters with a common dark floor rests on the eastern rim three kilometers above the shadowed floor of Walther. To the west beyond the dark floor is the cratered, off-centered “central” mountain group casting a long triangular shadow across the resurfaced floor to crater Walter E (13 km.). Four small 4-6 km. craterlets can be seen in the drawing although at the eyepiece additional smaller ones were clearly visible in moments of steady seeing. To the northeast of Walther another large 3.9 billion year old crater Aliacensis (80 km.) was showing terraced walls and a central peak. The large younger Eratosthenian crater to the north of Walther is Werner (71 km.). Like the other two it has an off-centered central peak as well.

This was one of those observing nights when you wish time would stand still. I watched the long triangular shadow from Walther’s central peak shorten by 40% in just 2 hours.
I must say this was a beautiful night for moon viewing.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, 9”x 12”, white and black Conte’pastel pencils and a blending stump. Brightness was slightly decreased (-2) and contrast increased (+2) after scanning using Microsoft Office Picture Manager.

Telescope: 13.1 inch f/ 6 Dobsonian and 6mm eyepiece 333x
Date: 5-13-2008 1:35 – 3:20 UT
Temperature: 7° C (45° F)
high clouds, calm
Seeing: Antoniadi III
Co-longitude: 4°
Lunation: 7.6 days
Illumination: 59.7 %
Phase: 78.8°
Observing Location: +41°37′ +87°47′

Frank McCabe

Pen and Ink Petavius

Petavius Crater
Sketch by Michal Repik

Michal Repik is a seventeen year old amateur astronomer from the Czech Republic. He has been sketching his astronomical observations for the last three years.

Information about the observation:
Date: May 5, 2008
Time (UT): 21:10
Telescope: Maksutov
Aperture: 127 mm
Focal Length: 1500 mm
Magnification: 200x
Observation place: Prague
Lunar colongitudo: 312.6°
Seeing: 2/5 (ant.)