Media Combinations – Page 29 – Astronomy Sketch of the Day

Exquisite Eratosthenes

Eratosthenes and environs
Sketch and Details by Richard Handy

Description: Eratosthenes is the exquisite jewel sitting next to the Hope Diamond of Lady Luna, Copernicus. Consequently, Eratosthenes is often overshadowed by the spectacle of this lunar Juggernaut, however this sparkling gem of a crater and its immediate environment convey some of the major events that dominated the northwestern quadrant of the Moon. From 4.5 billion to 4.2 Billion years ago, a few hundred million years before the period of Heavy Bombardment, the large impactor Gargantuan, first proposed by the British geologist Peter Cadogan, struck the Moon with a force and fury far beyond our comprehension. The possibility that this impact could have, in one single event, reshaped the mean crustal thickness on both sides of the Moon is a staggering thought. Fed by fissures and cracks in the broken crust created by the force of the impact, magmas found easy passage to the basin floor. Over the intervening eons, the great basin formed by that event would eventually fill in with mare lavas to form Oceanus Procellarum. About 3.85 billion years ago, during the period of Late Heavy bombardment (3.8-4.0 by ago) the Moon received another enormous blow to this same northwest quadrant. The impactor, though half the size, formed another great basin, again flooding with mare lavas like Procellarum, to become the beautiful Mare Imbrium. To the east of Eratosthenes, the arcuate sweep of the Montes Apenninus, part of the remnant rim of giant Imbrium, seem to diminish to a few low outcrops as they approach the crater, probably appearing much like a mesa would if you were strolling on the surface. There are a few of these buried massifs on Eratosthenes’ northwestern flanks, although the great circular mountain range disappears in this region only to reappear as the Montes Carpatus to the northwest of Copernicus. There is a wonderful flame-like mountainous formation to the southwest of Eratosthenes, it appears to have been shaped by the fluidized flow fronts from the Imbrium event. Both Copernicus and Eratosthenes are benchmark features, meaning their formations correspond to the beginning of a geological period. Fifty-eight kilometer Eratosthenes was excavated by a 3 km wide impactor some 3.2 billion years ago. It’s rugged walls and terraces show significant scalloping and craterlet battering. The mare around Eratosthenes seemed coated in rays from 93 km Copernicus, which formed 1.1 billion years ago by an impactor 4.5 km in diameter, inaugurating the Copernican period. During this last 1000 million years most complex plant and animal life on Earth evolved.

Sketch details:
Subject: Eratosthenes and environs
Date: 12-28-2006 Start 5:27 UT End 6:50 UT
Lunation: 8.64 days Phase: 68.6 deg Colongitude: 19.8 deg
Illumination: 68.2 % Lib in Lat: -03 deg 24 min Lib in Long.: +01 deg 36 min
Seeing: Terrible most of the session, Antoniadi IV-V, only very occasionally III
Weather: clear
Telescope: 12” Meade SCT f/10
Barlow: 2X Televue
Binoviewer: Williams Optics Bino-P with 1.6X nosepiece
Eyepieces: 20 mm W.O. Plossls
Magnification: 396X
Sketch Medium: White and black Conte’ Crayon on textured black Strathmore paper
Sketch size: 18”x 24”

Luminous Goldschmidt

Craters Goldschmidt, Anaxagoras and Epigenes
Sketch and Details by Frank McCabe

Crater Goldschmidt is an ancient pre-Nectarian period walled-plain crater that is situated only 480 km. from the lunar North Pole. The floor of this crater appears light in color and little crater Goldschmidt A (7km.) was seen on the southern floor.
Along the western rim of Goldschmidt are craters Anaxagoras (53 km.) and Anaxagoras A (18 km.). Anaxagoras is a young Copernican period crater with an expected ray system that includes some I saw during the observation and included here to the east and southeast. The crater to the southwest of Goldschmidt is Epigenes (55 km.), an ancient Nectarian period crater with a more typical dark floor for this region. With the moon crossing the meridian so low it never resolved well in the eyepiece and scintillated and shimmered in the warm air rising from the ground. All in all it was a wonderful opportunity to view and sketch the moon.

Sketching

For this sketch I used: black Strathmore 400 Artagain paper 10”x10”, white and black Conte’ pastel pencils and a blending stump. After scanning, Brightness was decreased (-5) and contrast increased (+5) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 6 mm eyepiece 241 x
Date: 7-14-2008, 2:20-3:40 UT
Temperature: 20° C (68° F)
Partly Cloudy, calm
Seeing: Antoniadi III-IV
Colongitude 41.9°
Libration in Latitude: +7° 19’
Lunation 11 days
Illumination 84.3 %

Frank McCabe

Dark Nebula Nexus

M20 – The Trifid Nebula
Sketch by Kiminori Ikebe

Mr. Ikebe observed and sketched this view of M20 using a 50 cm Dobsonian at 220X.

M20, The Trifid Nebula, is a famous and beautiful target for astrophotographers and visual observers alike. The red emission nebula contains a young star cluster at its center, and is surrounded by a blue reflection nebula that is most noticeable at the northern end. It’s distance is not well agreed upon, and is listed anywhere from 2,200 light years (Mallas/Kreimer) to 9000 light years (Jeff Hester). Its magnitude estimate is also wide, and is listed from 9.0 (Kenneth Glyn Jones) to 6.8 (Machholz). Part of the magnitude difficulty comes from the very bright triple-star system at the heart of the nebula.

The dark nebula that crosses the Trifid was cataloged by Barnard and listed as B 85. The object was originally cataloged by Charles Messier in 1764, when he described it as a cluster of stars.

Six Degrees of Libration

Lunar Crater Barrow
Sketch and Details by Frank McCabe

With six and one half degrees of libration in latitude, the lunar North Polar Region was favorably positioned for viewing from our home planet. A morning sun ray was illuminating the floor of crater Barrow as I set up my scope for an evening of observing the moon and stars. I was not expecting to sketch the moon tonight because of its low altitude. I just couldn’t pass up this opportunity to catch this sight on the floor of Barrow and a sketch was in order.

Crater Barrow is an old worn 95 km. Nectarian period impact dent adjacent to larger older walled plain crater Meton (126 km.). Meton appears particularly large and irregular in shape because of the common lava flooded floors of Meton, C, D E, and F. Much smaller and younger crater B (6 km.) can be seen on the floor of Meton C (77 km.). It was only after I began sketching that I noticed a second ray of sunlight crossing the floor of Scoresby M (54 km.) just to the north of Barrow. Other craters visibly here include: Scoresby (57 km.) one of the younger craters here with the brightly lit rim and just northeast of M, Challis (56 km.) and Main (48 km.) are paired up to the north of M.

Part way through the sketching process I needed to move the entire setup because I lost the moon to a large maple tree. This was a most rewarding observing session even with a moon that tried to hide from my vantage point.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper 12”x14”, white and black Conte’ pastel pencils and a blending stump. After scanning, Brightness was slightly decreased (-4) and contrast increased (+4) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 6 mm eyepiece 241 x

Date: 7-10-2008, 1:45-2:50 UT

Temperature: 22° C (72° F)

Partly Cloudy, calm

Seeing: Antoniadi III

Colongitude 353.1 °

Libration in Latitude: 6° 30’

Lunation 7 days

Illumination 49.2 %

Frank McCabe

Grabbing The Horns of 1058

The Waxing Crescent Moon, Lunation 1058
Sketch and Details by Frank McCabe

Waxing Crescent Moon: Lunation 1058

This was the beginning of a wonderful observing night. I started observing and sketching the moon well before sunset and finished sketching before twilight ended. Because of my early sketch completion, no evidence of earthshine was visible.

The current lunation number is 1058. A lunation number changes approximately at 29.5 days and between two successive new moons. This interval of time for the moon is also known as the synodic revolution of the moon as it returns to the same phase. Lunation number one was the first new moon beginning in 1923 with the first new moon of that year more than 85 years ago.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper 11” X14”, white and black Conte’ pastel pencils, crayons and a blending stump. Brightness and contrast were slightly adjusted after scanning.

Telescope: 4.25 inch f/ 5 Dobsonian and 21mm eyepiece 26x

Date: 7-5-2008 1:05-2:10 UT

Temperature: 20° C (68° F)

Clear with slight haze, calm

Seeing: Antoniadi III

Colongitude: 303.5 °

Lunation: 2.9 days

Illumination: 11.7 %

Frank McCabe

One Slim Sickle of Moon

Slim Crescent Moon in a Twilight Sky
Sketch and Details by Giorgio Bonacorsi

Hi Astronomy sketchers,how are you? I made this sketch one month later, the Moon was beautiful at sunset, i mount quickly my refractor of 80mm and i stay enchanted at that vision. Is the first time which made a sketch of the Moon in this phase.
I made this sketch with white pen on blue paper directly from eyepiece of telescope.
At next,clear sky and good sketches to all.

Site:Pergola,Marche,Center Italy.
Date:6 of May 2008.
Hour:8,41 p.m.
Instrument:Refractor Kenko 80mm,1000mm focal lenght.
Eyepiece:Hortoscopic Tele Vue 21mm.
Magnification:47x
Seeing: Good,no wind.

Giorgio Bonacorsi

Planet Five with Two Moons

Jupiter with Ganymede and Io
Sketch and Details by Frank McCabe

While spending most of the evening and night outdoors under the stars, I had an opportunity to sketch planet Jupiter as I awaited the moonrise.

Jupiter was not very high above my southeastern horizon but the seeing was quite good for my location. I was able to see the great red spot not far from Jupiter’s preceding limb on the southern edge of the south equatorial belt. The belt appeared bisected over most of the viewing area. Superimposed on the north temperate belt I was able to clearly see the shadow of Ganymede near the preceding limb. The satellite was lost in the front of Jupiter to the east of the shadow as it made its transit in front of the giant. Also visible in the field of view were moons Europa and further from the planet on the other side Io.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, 8”x 11”, and a white Conte’ pastel pencil. I added the moons to the black paper using the white pastel pencil. The sketch of Jupiter was done on white sketching paper using HB, 2B and 4B graphite pencils an eraser shield, and a blending stump. I carefully cut the sketch of Jupiter from the white paper and using a small piece of double sided carpet tape added it to the black paper. Brightness was slightly decreased (-4) and contrast increased (+3) after scanning using Microsoft Office Picture Manager.

Telescope: 10 inch f/5.7 Dobsonian and 6mm eyepiece 241x
Date: 6-23-2008 4:25 – 4:55 UT
Temperature: 15°C (59°F)
clear, calm
Seeing: Pickering 7.0

Frank McCabe

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

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

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