Charcoal – Page 3 – Astronomy Sketch of the Day

Gassendi Crater

Gassendi Crater
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2012 06 01, 0238 UT – 0446 UT Gassendi
PCW Memorial Observatory, Texas, Erika Rix
www.pcwobservatory.com

Celestron Omni XLT 102mm, 24-8mm Baader Planetarium Mark III Hyperion, 2x Barlow, 250x
Temp 71° F, 60% humidity, S: Antoniadi II, T: 5/6
Eyepiece sketch black Strathmore Artagain paper, Conte crayon and pastel pencil, charcoal pencil
Phase: 45.8 deg, Lunation: 11.21 d, Illumination: 84.8%
Lib. Lat: +05:08, Lib. Long: -04:13
Az: +209:11, Alt: 41:03

Located on the northern border of Mare Humorum, crater Gassendi is an impact crater formed during the Nectarian period (-3.92 to 3.85 billion years ago) that later was modified after volcanic activity, becoming a fractured-floor crater. Gassendi is believed to have been filled with lava from the inside, raising its floor, creating stress fractures in the process. This would explain it being considered a walled plain with a shallow depth of 2.8 km. The central peaks (~1200 m high) remain and several rilles (called Rimae Gassendi) were formed on the lava-filled floor during the Imbrian geological period -3.85 to –3.2 billion years ago.

Crater Gassendi A was formed during the Copernician period (–1.1 billion years ago to the present day) and overlaps Gassendi’s northern rim. The pairing of Gassendi and Gassendi A resembles a diamond ring and makes a very striking feature to observe 3 days after first quarter or two days after last quarter of lunation. My observation was nearly three days after first quarter.

Gassendi’s southern rim was swallowed by the lava of Mare Humorum leaving only a thin crest line to support its circular shape. Dorsa ran from the southern rim to Gassendi O (11 km wide). The sharp ridge that defines the border of Mare Humorum to the SW of Gassendi adds to the crater’s unmistakable identification.

At the beginning of my session, Spica and Saturn lined up to align with the Moon. Spica was 2.08 degrees north of the Moon and Saturn was 6.9 degrees north of the Moon. Extending further north, Arcturus was nearly in line as well at 31.8 degrees north of the Moon

An Interesting Contrast – Riccioli and Grimaldi Craters

Riccioli and Grimaldi Craters
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Aloha!

After a bit of a slump, I decided to get out & observe a little of our Moon. On the lunar west limb I spotted 2 craters that appeared so different from one another that I was intrigued. I knew that one was Grimaldi but was not certain about the other. I sat down to sketch at the eyepiece on a night of good seeing conditions in Hawaii.

Riccioli Crater is the large (140 km) lunar impact crater at the western terminus of the sketch. It is bordered to the southeast by the larger (230 km) Grimaldi & to the northwest by Hevelius. Hedin is still in the darkness and only the edge becoming lit.

Riccioli appears elongate with rough crater walls casting sharp jagged shadows into the basin. There is also visible roughness & debris within the crater. This debris & other striated formations in the region are believed to have been created by ejecta from the formation of the Orientale impact basin to the southwest not seen here. The roughness of Riccioli is in stark contrast to Grimaldi which appears smooth by comparison. Grimaldi, covered in lava makes it appear more like a mare than a crater.

There appears to be a dark line or peak running from Riccioli to crater Lohrmann directly to the east. Multiple small brightly lit rimmed craters surround this area. A double crater with 2 bright rims of light can be seen at the northeast edge of Riccioli.

Both Riccioli & Grimaldi craters were named by 17th century Jesuit priests & colleagues Francesco Maria Grimaldi & Giovanni Baptista Riccioli, who were responsible for many of the names given to features on the Moon today.

Thia (Cindy) Krach
12.5” Portaball 169x
Maui, Hawaii
4/23/13
Black Fabriano paper
white & black charcoal pencils

Sirsalis and Damoiseau

Sirsalis and Damoiseau Region
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Aloha,

I submit a lunar sketch of the Sirsalis & Damoiseau region bordering Oceanus Procellarum at the western region of the Moon created almost a year ago. What a wonderful area to explore with interesting concentric craters of Damoiseau & the double crater of Sirsalis at this angle of light. Unseen Grimaldi lies in the darkness to the west.

Object: Lunar craters Sirsalis & Damoiseau @ ~13 days lunation
Telescope: 12.5” Portaball 9mm Nagler 169X
Location: Maui Hawaii, 4000 ft elevation
Date: 2/4/12 7:45pm
Medium: Black art paper, white & black charcoal

Thia (Cindy) Krach

Lunar Volcanism

Hi all,

I’ve been itching to have a go again at Alphonsus for some time. Along with its two buddies, Arzachel (to left) and Ptolemaeus (at right), this trio are a time line of Lunar history.

Ptolemaeus is the oldest. The crater floor is totally flooded, even the central peak is covered. It was fromed when the Moon was still very hot and lava readily flowed with a large impact.

Arzachel is the youngest. The crater floor is intact with no flooding, the crater walls are terraced with land slides both inside and outside of the crater.

Alphonsus sits bewteen the two in age. The crater floor is only partially flooded with the central peak still visible. The Moon has cooled since Ptolemaeus and lava flow has slowed. BUT, volcanic activity was still occuring after the flooding process had stopped. This is seen from the pyroclastic deposits that sit within Alphonsus. Four deposits lie within this crater and are marked in the labelled pic, and are seen as the darker shaded areas that are easy to see through the eyepiece.

Quite remarkable to consider that from here on Earth we can see the effects of ancient volcanism on a body that isn’t Earth.

Another treasure of the night was the Celestron Ultima LX 8mm eyepiece I used. These eyepiece are much underrated, but are surprisingly good. The 8mm in particular is easy to use for extended viewing. It made the 2.5 hours much more bearable, and my eyes were not as fatigued as they have been after with other sketches that have taken less time to do. It’s one of my favourite eyepieces.

Object: Pyroclastic deposits in Alphonsus
Scope: C8, 8″ SCT
Gear: 8mm Celestron Ultima LX, 250X
Location: Sydney, Australia
Date: 19th March 2013
Media: Soft Pastel, charcoal and white ink on A4 size black paper
Duration: approx 2.5 hrs

Pyroclastic deposits in Alphonsus - Labeled — Pyroclastic deposits in Alphonsus – Labeled

Comet PanSTARRS and the 1 Day Old Moon

On the evening of March 12, 2013, I was treated to a pleasant view of the 1.26 day old Moon (1.8% illuminated) and comet C/2011 L4 Pan-STARRS from 07:00pm to 07:20pm local time Mesa, Arizona. I had an excellent view of the clear western sky and I could see the comet naked eye about 6.5 diameters to the south of the Moon.

To assist in making the rough graphite sketch I used a 5x 50mm finder scope removed from an Orion telescope. After returning home from Arizona to Illinois I made a color drawing from field notes and the graphite sketch. I was planning on a color sketch but the number of colors need and blending seemed too much for the 30 minutes to comet set.

Sketching:

Graphite pencils: 6B, 4B and 2B also black and white pastel pencils on white sketching paper.

Color drawing was made with black and white charcoal pencils and an assortment of color pencils on medium blue paper.

Frank McCabe

NGC 7354 – Planetary Nebula in Cepheus

2012 08 16, 0400 UT

NGC7354/PK 107+2.1 (4+3b)/H II-705

Planetary nebula in the constellation Cepheus, 22h 40.4m, +61deg17´, 0>20´, m12.9v

Erika Rix – Liberty Hill, Texas

www.pcwobservatory.com
16” Zhumell reflector f/4.5 on a non-tracking Dobsonian mount, Baader Planetarium Hyperion 8-24mm Mark III (75-225x magnification)

82.4°F, 54% H, 9.2 SSE winds, clear, Pickering 6, T 2/6

NGC7354 is a small, slightly faint planetary nebula in Cepheus. Through the telescope, it is located the middle of a star pattern that resembles Sagitta where Delta Sagittae would have been. The star pattern consists of TYC4265-877-1 (m11.7) and USNO J2240137+612011 (m13.2) to the north with TYC4265-347-1 (m10.68) to the south. A strand of three other stars to the west, along with the pattern of stars that resembled Sagitta and NGC7354, resembled the shape of an ear or an ammonite fossil.

75x magnification: Small, soft circular disk, with a hint of slight elongation. O-III adds contrast and there was a hint of brightness in the center of it. A 14.75 magnitude star to the southwest and a 15.3 magnitude star to the southeast of NGC7354 were observed at this magnification just outside of the disk.

225x magnification: A third star with a magnitude of 14.9 was observed just outside of the disk to the west. Using an O-III, the NE and SW edges of the disk were fainter and I could see a brightened edge to the nebula around the rest of the disk with a fainter center. I detected a faint, diffuse haze outside of the brighter borders and there may have been a hint of the central star as it looked slightly grainy in the center of the disk.

Sketches created with AL template, #2 graphite pencil, loaded blending stump with charcoal, super-fine Faber-Castell Pitt artist pen “S”, 0.5mm mechanical pencil.

The ET Cluster

ASOD – E.T cluster NGC457 sketch – “Kim byong su”
object Name – E.T cluster NGC457 sketch
Location – But-gogae Gosong-ri Yangdong-myeon Yangpyeong-gun Gyeonggi-do S.KOREA
Media – pencil, charcoal , white Paper(croquis book)

XQ 10″ Dob / Explore 9mm 100′(2 inch)= “138x”

Occultation of Jupiter by the Moon – December 25, 2012

Occultation of Jupiter - December 25, 2012

Ocultação de Júpiter pela Lua 25.12.12
Object Name – Planet
Location – Rio de Janeiro / Brasil
Date – 25.12.12 / 20:42 h UTC
Media – graphite pencil, charcoal, white paper, photoshop

Equipament –
130 mm / f 6.9 / EQ2 Newtonian Telescope
Ocular 25 mm Kellner
Stellarium

Crater Goclenius

The seeing was better than usual on November 18th, so I decided to use a high magnification on my C6, and see what would catch my eye.

Near the edge of Mare Fecunditatis, craters Gutenberg and Goclenius stood out, with two rimae running in from the north west.

I zeroed in on the crater Goclenius itself. The Rimae run right into it. The shadows were quite stark, revealing the broken down crater walls, and the fractures on the floor were very apparent.

A pencil sketch was done at the eyepice, and a photo taken. The final sketch was then completed at leisure a couple of weeks later.

Details:
Crater Goclenius, C6 (150mm SCT, 3 x Barlow)
Adelaide, South Australia, November 18th 2012.
Medium is charcoal on white paper.

-Ivan

Omega Nebula M17

file name – “1280 m17 omega joong_asod”
object Name – Omega Nebula M17
object Type – Omega Nebula M17
Location – But-gogae Gosong-ri Yangdong-myeon Yangpyeong-gun Gyeonggi-do S.KOREA
Media – pencil, charcoal , white Paper(croquis book)

XQ 10″ Dob / Explore 9mm 100′(2 inch) / Orion UltraBlock(NarrowBand 2inch)

Supplemental Image Link