Conté Pencil – Astronomy Sketch of the Day

Crater Davy and its Crater Chain in Davy Y

Crater Davy (35 km.) and the Davy crater chain (catena) were my targets for this evening of sketching and although the seeing and transparency were predicted to be above average that was not the case.
The Davy crater chain is 45-50 km. in extent. It arcs across the floor and eastern rim of crater Davy Y (70 km.). Since it does not line up with any impacts of note it is not likely a sequence of secondary craters. There is also no evidence of volcanic activity associated with this chain. Robert Wichman and Charles A. Wood as well as H. J. Melosh and E. A. Whitaker believe that a comet (or asteroid) may be responsible as it broke up while inside the Earth’s roche limit. As it went in on the moon like a train of meteors it would have created a chain of impacts. A paper published in 1994 by Melosh and Whitaker explains the hypothesis.

Crater Chains on the Moon: Records of Comets Split by the Earth’s Tides?; H. J. Melosh and E. A. Whitaker, Lunar and Planetary Lab, University of Arizona, Tucson, Az.

Sketching:

Black Artagain paper, white and black Conte’ pastel pencils, white Pearl eraser, blending stumps

Telescope 13.1” f/6 Dobsonian telescope on an equatorial drive platform at 332x with 6mm eyepiece

Date: 03-29-2015, 00:00 – 03:00 UT

 Temperature: -5°C (24° F) clear, calm
 Seeing: Variable, Antoniadi III(fair)-IV (poor)
 Colongitude: 11.6 °
 Lunation: 8.4 days
 Illumination: 64.7 %

  Frank McCabe

Crater Davy - Labeled — Crater Davy – Labeled

Apollo 15 Landing Site

Apollo 15 Landing Site
Last evening proved to be a fine night for observing the Moon and the planets. The atmosphere at sunset settled down to a Pickering 8/10 and 9/10 for brief intervals. This was predicted so I had two telescopes outside (my 18 inch f/4.9 and 13.1 inch f/6 both Dobsonians). At 373x using the 18 inch scope I could clearly see the floor of Palus Putredinis (The Marsh of Decay) and not far away Rima Hadley at the foot of Montes Apenninus. I spent a 3 hour interval on this sketch but actual sketching time was more like 2 hours. The sketch was done using the smaller scope because it is driven. 4 mm and 6 mm eyepieces gave me magnifications of 499x and 333x and occasionally I used the 18 inch scope to verify some of the meanders of Hadley rille and other small features. I have marked the landing site (red dot) of Apollo 15 Lunar Landing Module which occurred the summer of 1971, a very exciting time for the US space program.
Craters visible in this sketch include Hadley C 6 km. in diameter and Aratus (10 km.).

Sketching:
For this sketch I used: Gray sketching paper, 9”x 11”, white and black Conte’ pastel pencils and blending stumps.
Telescopes: 13.1 inch f/ 6 Dobsonian and 18 inch F/4.9, eyepieces : 4mm, 6mm

Date: April 29, 2015 01:00-04:00 UT
Temperature: 4.4°C (40°F)
Clear, calm
Seeing: Pickering 8.5
Transparency: 4/5
Co longitude: 29.9°
Lunation: 10 days
Illumination: 75.9 %
Frank McCabe

Apollo 15 Landing Site - Labeled — Apollo 15 Landing Site – Labeled

Craters Diophantus and Delisle

On the western side of Mare Imbrium are craters Diophantus (19 km.) and Delisle (25 km.) with mons Delisle in between and closer to the crater of the same name. A dorsum or ridge here is perhaps a buried crater rim and creates a sharp edge curving demarcation on the terminator side of the Moon at the time of sketching. Some of the massifs in this region such as mons La Hire (1.5 km. high), mons Vinogradov (1.4 km.) and mons Delisle( 0.8km. high) are described by some geologists as likely left over remnants from the rings of the Imbrium impact. Additional craters seen at this observation included Euler (2.8 km.), Artsimovich (9 km.), Gruithuisen (17 km.) and Heis (15 km.)and numerous smaller unnamed.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, 9”x 12”, white and black Conte’pastel pencils, a soft charcoal pencil, brush and a blending stump.

Telescope: 13.1 inch f/6 Dobsonian and 9mm eyepiece 221x
Date: 01-31-2015, 03:10 – 04:25 UT
Temperature: -7°C (20°F)
clear, breezy
Seeing: Antoniadi III
Co longitude: 38.7°
Lunation: 10.33 days
Illumination: 84.9 %
Phase: 45.8°

Frank McCabe

Comet and Globular

Comet C/2014 Q2 (Lovejoy) and the globular star cluster M79 in the constellation Lepus

M79 and Comet Lovejoy in Lepus

I have been monitoring comet Lovejoy (C/2014 Q2) for the past several nights and on this occasion they both shared the same field of view at130 power. I was using my daughter’s 10 inch Orion Dobsonian telescope and was able to capture this sketch under clear skies and good seeing conditions. The observation site was in eastern Mesa, Arizona with a good view to the south. The comet can be seen much brighter and larger in angular size than than 8.5 magnitude globular cluster M 79. This was a pleasing view at the eyepiece with the comet showing a hint of green color. I switched to 48 power and a wider field of view for the sketch.

Sketching:

White and Black Conte’ pastel pencils on black sketching paper
blending stump and Pink Pearl eraser also used
R.A. 05hr 24′ ; Dec. -24 degrees 33min.
Comet distance less than 100million km.
M79 distance 42,100 light years 150 million stars

Frank 🙂

Crater Posidonius at Sunset

Lunar crater Posidonius and environs at sunset - August 7, 2012 — Lunar crater Posidonius and environs at sunset – August 7, 2012

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

Lunar Crater Copernicus

Across the Carpathian Mountains resting on the eastern Ocean of Storms is the
landmark crater of the Sea of Islands, mighty Copernicus. Copernicus is a 95
kilometer diameter complex crater that begins to show itself in all its majesty
two days past first quarter. During the time of “Snow-Ball Earth” 800 million
years ago the event that created Copernicus suddenly occurred. What remains is a
3.8 kilometer deep hummock covered flat floored, centrally peaked, terrace walled
spectacular sentinel. Especially during high sun the bright ray system of this
crater can be seen extending from the base of the glassy glacis in all directions.
The descent from the rampart to the mare floor below is about one kilometer. Three
of five peaks were clearly visible in morning sunlight. In 1999 the Clementine
near infrared camera detected magnesium iron silicates in the peaks indicating
rebound of this deep rock through the surface crust following the impact event.
To view this impressive crater all you need is a good pair of binoculars and an
opportunity between two days past first quarter and one day past last quarter.
Weather permitting, you can see it tonight.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, 9”x 12”, white and
black Conte’pastel pencils and a blending stump.

Telescope: 13.1 inch f/5.9 Dobsonian and 9mm eyepiece 218x
Date: 11-03-2014, 00:45 – 02:10 UT
Temperature: 0°C (32°F)
clear, calm
Seeing: Antoniadi III
Co longitude: 23.2°
Lunation: 8.9 days
Illumination: 69.3 %
Phase: 67.4°

Frank McCabe

Early Morning Pitatus and Neighbors

Lunar crater Pitatus and environs - September 17, 2014 — Lunar crater Pitatus and environs – September 17, 2014

Lunar crater Pitatus and environs (labeled) - September 17, 2014 — Lunar crater Pitatus and environs (labeled) – September 17, 2014

Pitatus is an old, large 97 km. diameter crater on the edge of Mare Nubium. The floor of this crater has a linear central peak which was casting a fine elongated triangular shadow at the time of this observation and sketch. To the south craters Wurzelbauer (88 km.) and Gauricus (79 km.) could be seen; both of these craters show badly warn rims; both much older than Pitatus. Attached to the northwest rim of Pitatus is the crater Hesodius (43 km.). At about the eighth or ninth day of lunation you can observe the famous “sunrise ray” beaming across the floor of Hesodius through a break in the wall with Pitatus. This is certainly a sight worth observing.

Sketching:

For this sketch I used: Black Strathmore 400 Artagain paper, 12”x 9”, both white and
black Conte’pastel pencils and blending stumps.

Telescope: 10 inch f/5.7 Dobsonian and 9mm eyepiece 161x
Date: 09-17-2014 10:00-11:25 UT
Temperature: 5°C (42°F)
Clear, calm
Seeing: Antoniadi III
Co longitude: 187.3°
Lunation: 22.6 days
Illumination: 39.0 %

Frank McCabe

Another Look Near to the Altai Scarp at Higher Sun

The lunar craters Riccius, Rabbi Levi, Zagut and Lindenau near the Altai Scarp - July 4, 2014 — The lunar craters Riccius, Rabbi Levi, Zagut and Lindenau near the Altai Scarp – July 4, 2014

Riccius, Rabbi Levi, Zagut and Lindenau - Labeled — Riccius, Rabbi Levi, Zagut and Lindenau – Labeled

Two hundred or so kilometers to the southwest of the Altai Scarp you will find a mix of large and small highland craters that may catch your eye as they did mine. Many have written of the “boring” look-a-like craters of this region but good lighting can make a big difference in appeal here. Ancient Riccius crater (71 km.) is a worn, an almost obliterated remnant, covered and surrounded by crater from 10-15 km. of various ages. Adjacent to Riccius is crater Rabbi Levi (81 km.) with an interesting short chain of craters across its floor. The next crater Zagut (84 km.) is the largest of those in the sketch with Zagut A (11 km.) near the center of the floor and Zagut E (35 km.) pushed through the eastern wall of Zagut. Next to Zagut is crater Lindenau (53 km.) which is younger than the other large crater here as evidenced by the sharper rim and what looks like a part of a central peak remaining.
A fine summer evening of observing and sketching after a long spell of poor weather.
Sketching and Equipment:

For this sketch, I used black Strathmore 400 Artagain paper 8” x 12”, white and
black Conte’ pastel pencils and blending stumps.
Telescope: 10 inch f/5.7 Dobsonian and 6 mm eyepiece (241x) riding on an equatorial platform
Date: 07-04-2014, 01:15-02:50 UT
Temperature: 16° C (60° F)
Clear, calm
Seeing: Average – Antoniadi III
Transparency: 4.5/5
Colongitude: 349.0 °
Lunation: 6.7 days
Illumination: 36 %

Frank McCabe

Lunar North Polar Region

Lunar North Polar Region

For several nights this week the lunar North Pole has been tilted more towards earth due to favorable lunar libration in latitude. It has been a good opportunity to view craters such as Whipple, Peary, Byrd and others. I had a clear night with average seeing so I took advantage of the opportunity to sketch the illuminated region near the pole. At my location the Moon was at more than 60 degrees above the horizon which also helped with the time needed to complete a sketch.

Sketching and Equipment:

For this sketch, I used black Strathmore 400 Artagain paper 9” x 12”, white and

black Conte’ pastel pencils and blending stumps.

Telescope: 13.1 inch f/6 Dobsonian and 6 mm eyepiece (333x) riding on an equatorial platform

Date: 04-09-2014, 01:00-02:35 UT

Temperature: 3° C (38° F)

Clear, calm

Seeing: Average – Antoniadi III

Transparency 4/5

Colongitude 16.2 °

Lunation 9 days

Illumination 63.9 %

Frank McCabe

14.16-day-old Moon

Gibbous Moon - February 14, 2014 — Gibbous Moon – February 14, 2014

I’ve been doing a study on lunar phases and this is my latest sketch. This is a photo of it from last night after wrapping up my observing session. No adjustments have been made to the sketch other than cropping the lower blank portion of the paper.

My phase sketches used to take close to two hours to complete at the eyepiece. I’ve been building up my endurance to 3-4 hours for a single sketch to include more detail. Obviously, the terminator is drawn first to “freeze” the time stamp on the phase. Then I work my way across the disk at a more leisurely pace, moving my observing chair and stool gradually as the session progresses.

I used a 102mm f/9.8 refractor on an LXD75 mount, 20mm eyepiece setting on my Hyperion zoom, and a 13% T Moon filter to help with contrast. The media is black Strathmore Artagain paper (60 lb., 160 g/m2), white charcoal pencil, black charcoal pencil, white Conte’ crayon, white Conte’ pastel pencil, black Conte’ color pencil,and a blending stump for the maria. I used a circular 6-inch protractor to outline the lunar disk.

Total eyepiece/sketch time is just over four hours on this one.

Best regards,
Erika Rix
www.pcwobservatory.com
Texas, USA