Astronomy Sketch of the Day – Page 248 – Drawings and sketches of an astronomical nature

A Celestial Rorschach Inkblot Test

LDN 1795, a Dark Nebula
Sketch and Details by Dave Riddle

Located only two and one half degrees SE of the Galactic center, LDN 1795 may be one of the finest dark nebulae visible in small telescopes. Appearing as a prominent dark spot in my 11×80 finder, this dust cloud lies in front of the Great Sagittarius star cloud and exhibits an unusual shape as seen through my 18″ reflector at ~110x (20mm Nagler). I saw this inky cloud as either a horse’s head or the head of a Great Dane (making this cloud a kind of celestial Rorschach inkblot test!). John Herschel thought this field to be so extraordinary that he recorded two prominent “clusters” (now recognized as very dense Milky Way fields) in his Cape observation notebook. However, the concept of an obscuring cloud eluded him, although he would later admit that imperfectly transparent regions of space might exist. The idea of dark nebulae can be dated back to the mid-1700’s but it was clearly an idea ahead of its time. The digital drawing was done from a rude pencil sketch I made on the evening of July 21, 1998 from the dark rural skies of Panacea, Florida. As many of you know, drawing a dark nebula presents a challenge to the observer. Photoshop allows me to dispense with my pencil and eraser to make a finished drawing. With practice, I may get it right one of these days (nights)!

Dave Riddle

Marathon Moon

Hello, I’m newbie on ASOD!

I want to submit one of my drawings (1. Novembre. 2007)
Transparency: average
Seeing: very good (8/10, and it’s wonderful in Hungary…)
I used 8″ Newtonian telescope with 30mm and 10mm superplössl with 2.5x barlow and 1B-6B black pencils on white paper and made the final drawing in 15 hours. The sketch was made quickly as possible with ~80x and after that, I used 250x to terminator regions in 3.5 hours. (So, the migration of terminator is discoverable on the drawing, but – i think – unobtrusive. The full size of the drawing is A2.

Best regards:
Szabolcs Velkei

Coathanger for the Cloak of Night

The Coathanger Asterism, Collinder 399
Sketch and Details by Rony De Laet

Binocular Icon 21 : The Coathanger.

One of the highlights of a summer binocular tour of the heavens is Collinder 399. It is a loose group of stars, which is visible to the naked eye. The first written observations of this cluster go back to AD 946, when the Persian astronomer Al Sufi described Cr 399 as a little cloud. Cr 399 can be found between Cygnus and Aquila, a mere 5° west of Sagitta. From my backyard, I can detect a trio of stars in a little fuzzy spot. With a pair of binoculars, the cluster shows a real coathanger! Point the bino’s at Albireo and draw a line to Anser (Alpha Vulpeculae). Continue in the same direction until Answer nears the northern border of the field of view. Cr 399 should appear at the southern edge of the field stop of the binoculars. The Coathanger is an amazing sight, even under light polluted skies. The cluster consists of 10 bright stars. Six of them form the 1.4° long bar of the hanger, in a perfect east to west orientation. Cr 399 is believed to be a chance alignment and not a true cluster.

Site : Bekkevoort, Belgium
Date : June 10, 2008
Time : around 00.30UT
Binoculars : Bresser 8×56
FOV: 5.9°
Filter : none
Mount : Trico Machine Sky Window
Seeing : 2,5/5
Transp. : 3.5/5
Nelm : around 5.3
Sketch Orientation : N up, W right.
Digital sketch made with Photo Paint, based on a raw pencil sketch.

Above the Great Sand Sea of Namibia

47 Tucanae
Sketch and Details by Dave Riddle

It has been said that if we used all our senses to the fullest, we would stand in a constant state of amazement. Perhaps a telescope is merely a way to extend one of our senses — the gift of eyesight. I have come to appreciate how fortunate I have been to fulfill a few of childhood dreams. When the opportunity arose back in 2004 to visit Africa and take a five day road trip from Johannesburg, South Africa to the Great Sand Sea of Namibia, I jumped at the chance. I would spend eight weeks at the Sossusvlei Mountain Lodge under what must be some of the darkest skies found on our planet. The chance for daylight sightseeing combined with exploring the night skies of the southern hemisphere proved too much to resist…I’ll argue that the celestial wonders visible through a telescope are just as impressive as some of the other natural wonders seen along the way — the Augrabies Falls of S. Africa, the herds of elephants or the remarkable sand dunes of Sossusvlei. Submitted is a Photoshop rendering of 47 Tucanae, arguably the finest globular the heavens can offer. I used a 12″ Schmidt-Cassegrain at 250X to make the original graphite pencil and ink.

Dave Riddle

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.

A Surprising GC

M92, a surprising globular cluster in Hercules
Sketch and Details by Jeremy Perez

I didn’t realize how nice this globular cluster would look. It stood up well to magnification, with stars resolving across the face of the cluster. It appeared noticeably elliptical in its outer reaches, pointing southwest to northeast. The core was soft but robust. It seemed that the core’s brightness was harder along the north side, and faded more softly to the south. I would estimate its dimensions at 6′ x 4′. Also, the core seemed to reside closer to the south-southeast side of the overall body of the cluster. A bright yellow star hung about 6′ to the east of the core. Overall, the cluster gave the offhand appearance of an elliptical galaxy.

Factoids:
M92 is a globular cluster about 26,000 light years away in the constellation Hercules. It is a bit more distant than it’s brighter, neighboring cluster M13. An age estimate of 16 billion years is being re-evaluated based on new distance scale information for the universe from the Hipparcos satellite, and so may be a bit younger. Its 14′ extension yields a diameter of 109 light years, and may have a mass of about 330,000 solar masses. It is approaching us at 112 km/sec. The precession of Earth’s axis will cause M92 to become our “North Cluster” or “Polarissima Borealis” in about 14,000 years, as it was previously, about 12,000 years ago.

Subject M56 (NGC 6341)
Classification Globular Cluster (Class IV)
Position* Hercules [RA: 17:17.1 / Dec: +43:08]
Size* 14.0′
Brightness* 6.4
Date/Time June 30, 2005 – 11:00 PM
(July, 2005 – 06:00 UT)
Observing Loc. Flagstaff, AZ – Home
Instrument Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag. 10 mm (120X)
Conditions Clear, breezy, 68�F
Seeing 5-6/10
Transparency Mag 5.8 NELM
Sources SEDS
*Based on published data.

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

Star Child

Nebula
Watercolor by Ashley, age 10 and Details by Deirdre Kelleghan

This beautiful watercolor painting of a nebula has won a prize in the ESO’s Catch a Star 2008. The artist, a young lady, is a pupil in Saint Andrews Junior College in Blackrock, Co Dublin Ireland.
I was delighted with every Irish entry this year,each child will get a certificate of merit.
I am particularly proud of Ashley’s work. Well done Ashley !!!!!

Saint Andrews is a school member of the Irish Astronomical Society

Deirdre

Deirdre Kelleghan
President
Irish Astronomical Society 1937 – 2007
Public Relations Officer IFAS
http://www.deirdrekelleghan.com/
Oscail do Shuile D’iontas na Cruinne
Open Your Eyes to the Wonder of the Universe
http://homepage.eircom.net/~irishas/index.htm
http://www.irishastronomy.org/

Mobile 0872893828

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

Protubérances Solaires

Solar prominences
Sketches and Details by Cyprien Pouzenc

Bonjour !

Some prominences drawn at the 9 mm Nagler eyepiece, mounted on the
coronograph 107/1200 of the Sirene Observatory (www.obs-sirene.com) at
around 12pm on May 18, 2007 (! Yes, I was somewhat forgotten this
picture :o)

Lace… very difficult to render with graphite pencil !

Arch: drawn from 12:13 to 12:20 local time.
Shrubs: drawn from 11:57 to 12:06 local time.

—
Cyp

La Roque d’Anthéron (Bouches du Rhône, France)
+43° 43′ 03″ Nord, 5° 18′ 05″ Est, 175 m

CypASTROuille
Observatoire Sirene
Site NGC