Pencil – Page 194 – Astronomy Sketch of the Day

Checkmark LONEOS

C/2007 F1 (LONEOS)
By Martin Mc Kenna

Observation notes from Martin’s website entry:

Despite a poor sky with cloud, haze and chimney smoke along with a developing frost the sky cleared from the west on Oct 17/18th and I found the comet extremely quickly at 19.10 BST to the west and slightly south of Arcturus in the darkening evening twilight.

The coma was thin, compact, very well condensed with clearly defined edges where the coma meets the sky. It was wrapped tightly around a large white disk-like central condensation with a tear drop appendage from which a long spine ran into the tail. The coma was elongated away from the Sun and sported several fanning streamers similar in profile to a ‘shuttle cock’. The coma was a white-grey tone however no green could be seen.

The ion tail was blue, very straight, extending for 1 degree to the W of N and broadened with distance away from the Sun. Delicate long blue streamers could be glimpsed in fleeting moments of good clarity. I suspect the tail is MUCH longer than this. I was able to confirm something I have suspected since the morning of the 16th – a faint dust tail visible to the E of N leaving at a shallow angle from the coma perhaps 5′ long. The leading sunward edge of this tail is the brightest component. It will be interesting to watch its development. This is my best evening view of the comet to date.

Lost the comet to cloud so I did a little deep sky work then watched the waxing crescent Moon with earthshine set over the mountains with compact orange corona and long but faint pillar. For icing on the cake a V-shaped formation of geese flow overhead calling as they headed to the NE with bellies and wings lit orange from the town lights!.

Mag+ 6.0 Dia: 3′ D.C: 7/

Martin’s gallery of comet sketches can be found here:
Nightsky Hunter – Comet Sketches

Tuning in to a Cloven Galaxy

Fifteen million light years away in the constellation Centaurus lies the nearest radio galaxy, NGC 5128. Also known as Centaurus-A, it is categorized as an intermediate galaxy type, with qualities of both an elliptical (which describes its main body) and spiral galaxy (due to the prominent dust band encircling it). Loads of information about this fascinating galaxy can be found at the solstation website. This galaxy’s beautiful and unusual structure has been made famous through astro photographs, but it is also accessible to astronomical sketchers.

This sketch of NGC 5128 by Eiji Kato, was made at the Twinstar Guesthouse Observatory in Queensland, Australia. He notes: “As for my sketch of NGC 5128, it was made at Ballandean using my new 18″ f/4.5 (Galaxy Optics) mirror at 290x (Naglar 7mm eyepiece). It was drawn on white paper with black graphite, and then inverted after scanning. I am still working on this object for further refinement, but have to wait until next season as it is too low now.”

More of Eiji’s deep sky and comet sketches can be found in his gallery. (Note that a few of the links are broken, but don’t let that discourage you from viewing his excellent work.)

Pillars and Threads of Plasma

Solar Prominences and Filaments
By Erika Rix

Erika’s composite solar H-Alpha sketch from October 29, 2007, features prominences along the eastern limb as well as delicate filaments on the solar disc itself. Material used: black Strathmore Artagain paper with a combination of white Conte’ pencil for the brighter, more dramatic areas and white Prang pencil for the fainter areas.

A Brilliant Irony

Venus
Terrestrial Planet
By Eric Graff
Parks Astrolight EQ6 • 6″ f/6 Newtonian Reflector
7.5mm Parks Gold Series Plössl + 2x Barlow • 240x, 13′ FoV
30 September 2007 • 13:00-13:30 UT

It is somewhat ironic that the most brilliant planet in the sky is also the most challenging to observe. On 30 September 2007 Venus appears as a dazzling crescent (32% illuminated) in the morning sky, 42° west of the Sun and shining at magnitude –4.7.

This observation was made during morning twilight and the white cloud-tops of Venus displayed a fair amount of subtle, dusky shading, seemingly in a series of roughly parallel arcs curving northward. The shadings were most prominent toward the terminator, while the polar-regions were quite bright, particularly the southern cusp. In spite of the atmospheric subtlety, I found the observation of the large Venusian disk quite relaxing and relatively easy compared to the previous observation of the tiny Martian disk.

A Cluster on the Doorstep of the Trifid

M21
By Wade Corbei

This is an Open Cluster found in Sagittarius that contains a lot of stars of varying magnitudes, and lies close to M20 (Trifid Nebula). According to my notes, this OC was completed over the course of two evenings due in part to its location in the sky. It slipped behind some trees to my south on the first night, so I had to finish the sketch the following evening. Total sketching time at the EP was, I believe, approximately 1.5 hours.

A nice OC that fills up the entire FOV in a low-power EP.

The Eye of the Coppery Orb

Mars
Terrestrial Planet
By Eric Graff
Parks Astrolight EQ6 • 6″ f/6 Newtonian Reflector
7.5mm Parks Gold Series Plössl + 2x Barlow • 240x, 13′ FoV
30 September 2007 • 12:30-13:00 UT

The December 2007 opposition of Mars will pale in comparison to the very favorable oppositions of 2003 and 2005, achieving a maximum angular diameter of 15.9″ on 18 December 2007. On the other hand, it will not appear this large again until the opposition of 2016; also, unlike the previous two favorable oppositions, the Red Planet rides high over the northern crest of the ecliptic, placing it nearly overhead as it crosses the meridian for northern hemisphere observers.

On 30 September 2007, the Martian disk measures a mere 9.6″ and still shows a strong gibbous phase (the disk is 87% illuminated). The central meridian (CM) at the time of observation was approximately 110°. The principal Martian surface features identified during this observation include the dusky circular feature Solis Lacus drifting toward the terminator and the dark band of Mare Sirenum emerging from the limb. The Tharsis plateau, home of Mars’ mighty shield volcanoes occupies the relatively featureless golden plain near the center of the disk. Bright patches were detectable in the vicinity of both the north and south poles; I’m not sure whether these are the actual polar ice caps or “polar hoods” which are atmospheric mists associated with the evaporation of the caps. A few other patches of haze were detected around the southern limb.

Outburst of Comet Holmes

Many veteran comet observers regard the outburst of Comet Holmes (17P)
as one of the oddest sights they have seen. Not only was the sudden
brightening unprecedented in modern times, but the perspective we have
of this distant comet gave it an appearance all its own. From night to
night you can see it growing in size and yet, due to the dimming of the
expanding coma, it maintains a fairly constant brightness when viewed
naked eye.

Initially, the first images of this comet online indicate that is
difficult to capture the visual appearance with our imaging technology
and sketching is proving to be a satisfactory way to convey the visual
perspective at the eyepiece. I quickly opted for the sketching option,
but soon found that I had trouble getting a perfectly round coma that
also conveyed the contrasty ‘pop’ that this comet presented that first
night after announcement of the outburst. So instead of just using
image processing programs to get my onscreen-sketch looking like my
on-paper sketch, I decided to try to do more than embellish it and do
the sketch entirely with the image processing program. I refer to this
as digi-sketching.

So here is a series three ‘sketches’. The first is my original ‘paper
sketch’ captured and rendered to reflect what I had on paper. It was
graphite on paper with the colour added digitally.   It was
disappointing to me in that the brightness, contrast and the colourful
‘pop’ factor of this weird sight in northern Perseus was not entirely
captured.   The second sketch is my digi-sketch version of that same
night based on my original sketch. I soon appreciated that I could
quickly and easily correct some failings of the original.   The third
sketch is from three days later and is done to the same scale showing
the dramatic changes that took place in this short span of time. The
image processing program that I used for teh last two images is a PC
version of iPhoto that came with an old scanner. This makes me wonder
what is possible with some of the newer and more capable image
processing programs.

All three sketches were done from my view through a 12.5 inch home-made
Dobsonian using a Discovery mirror.   Binoviewers 23mm eyepieces and a
2x barlow gave a magnification of something well over 250x.    The first
two sketches are a result of my observations on the night of October
24th at around 10:45 CDT (UT 3:45 Oct 25th 2007).   The third sketch was
done on October 27 CDT at 11 PM (UT 4:00 on Oct. 28th 2007).   Note the
two 11th magnitude stars that could be seen shining through a relatively
colourless coma in this third sketch (bottom/south part of the coma
about 1/4 the way in). Since the equipment is constant for both nights,
the images can be directly compared for size and this gives one an idea
of just how quickly this comet grew in size.

This has to be one of the oddest and most unusual events in comet watching.

Gerry Smerchanski

Necre Hearted Visitor

Comet 17/P Holmes

I just couldn’t resist doing a quickie of this very unexpected object. As you may know, comet 17/P Holmes went from an unobscure magnitude 17 to 2.8 in just a little more than 24 hours…which it is now easily seen naked-eye in the constellation Perseus!! The coma is very bright and just a tad off-center, and the surrounding gases are emitting a slight off-yellow color. This comet does not (at present time) display the familiar “tail” that we are used to seeing with other comets, but this is still spectacular to see. Grab your scopes and head outside to see this beauty!!!

I will be observing this excellent and unexpected comet throughout the night and complete many sketches of this comet with differnt EP’s/magnifications. But for now, here is what it is looking like:

Wade V. Corbei
Lodi, California

A Promenade Through a Royale Garden

IC1396, a promenade through the Royale Garden.

One of the known highlights of Cepheus is Mu Cephei, a deep orange star. This night Mu Cephei served as the guiding light to IC1396. This region is a beautiful field of stars. There was something peaceful about this place. I felt like strolling through an exotic garden covered with haze. The place seemed majesticaly silent with Mu Cephei as a guard of honour at the border of the eyepiece. I don’t know if I saw IC1396 at all. I just noted all the light I could absorb in this field. A strange fact is that Mu Cephei kept his orange color through the UHC filter.

Date : October 13, 2007
Time : 21.00UT
Scope : Skywatcher 102/500
Meade SP 26mm
Power : x20
FOV: 150′
Filter : Lumicon UHC
Seeing : 3.5/5
Transp. : 3/5
Nelm : 5.3
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

Rony De Laet
Belgium

On the Tail of a Comet

I had a few failed attempts at spotting comet C/2007 Loneos before we finally met.

I caught up with it about 4 degrees below Arcturus in the evening twilight low in
the west to North western sky. With the Moon at around 50% on the eve of the 19th
October this didn’t help detection either. My village is in a hollow so to get a
good horizon I need to walk about half a mile along a track which runs up a hill
at the edge of the village ( Capon’s Hill). I used an old 6″ (150mm) F5 Helios
refractor on an alt-azimuth mount, slung it over my shoulder and set off. Equipped
with a couple of eyepieces and a BAA locator chart. I found it within a few
minutes of commencing the search. The tail was very hard to pick out in the orange
murk of the horizon although the head and coma with bright nucleus showed a hint
of a blue/green tinge. I nudged the scope to initiate movement and employed every
bit of averted vision I could must muster in an endeavour to detect what I felt
(at the time) to be a realistic interpretation.

The eyepiece I used was a 22mm Nagler so I feel the tail in the sketch equates to
around 0.75 of a degree. I tried again the following evening and located the comet
with a little more difficulty but couldn’t detect the tail at all, the 65% Moon
had washed it away.

Guess that I was lucky to have picked the interloper out when I did.

Sketch made in a A6 sketch pad with a HB Derwent pencil and blending stump,

scanned image turned into a negative in photo-shop.

Clear Skies,

Dale Holt, England