Extragalactic Twins

Extragalactic Twins 

The interacting galaxy pair consisting of NGC 3166 and NGC 3169 is one of the unsung extragalactic showpieces of the spring sky.  They may be located in the north-central region of Sextans, 8.5° south of Regulus.  Separated by 6.3′, these two galaxies look like nearly identical twins in my 6-inch scope; they give the strong impression of a ghostly pair of eyes peering from beneath a star-studded hood.  NGC 3166 is slightly smaller and dimmer than its companion but it has a more conspicuous central region with a sharp stellar nucleus.  NGC 3169 also has a bright core but it is not as well concentrated as its neighbor’s.  A 12th magnitude star is superimposed on NGC 3169’s diffuse outer halo, just east of the central core.  With a magnification of 60x and placing NGC 3169 near the northeastern edge of the field of view I can just squeeze in the faint galaxy NGC 3156 just west of a trio of 7th, 8th, and 9th magnitude stars (it lies just 2′ from the faintest of the three stars).  This little galaxy is elongated northeast to southwest and has a slightly brighter center.  A much fainter galaxy, NGC 3165, glimmers intermittently with averted vision 5.4′ southwest of NGC 3166.
William Herschel discovered NGC 3166 and NGC 3169 on December 19, 1783 with his 18.7-inch reflector.  He designated them as the 3rd and 4th entries (respectively) in his catalog of “Bright Nebulae”.  Both of these galaxies are included in the popular “Herschel 400″ observing list.  Each of these galaxies shows evidence of tidal interaction and distortion on photographs.  NGC 3169 has a highly distorted spiral arm, while the dust lanes of NGC 3166 have been fragmented and twisted as if
the entire disk has been warped by the interaction with its neighbor.  It is estimated that these galaxies lie 52 million light-years away.

Subject: NGC 3166 and NGC 3169
Object Type: Interacting Galaxy Pair
Constellation: Sextans

NGC 3166 (H.I.3)
Right Ascension (2000.0): 10h 13m 45.8s
Declination (2000.0): +03° 25′ 30″
Magnitude: 10.4
Diameter: 4.6′ x 2.6′
Classification: SAB(rs)0/a

NGC 3169 (H.I.4)
Right Ascension (2000.0): 10h 14m 15.0s
Declination (2000.0): +03° 27′ 58″
Magnitude: 10.2
Diameter: 5.0′ x 2.8′
Classification: SA(s)a pec

Observer: Eric Graff
Location: Cuyamaca Mts., San Diego Co., California (4,000 ft. elevation) Date &
Time: 12 March 2007 at 07:35UT
Transparency: NELM 6.7, TLM ~14.1
Seeing: Pickering 5-6/10
Telescope: Parks Astrolight EQ6 (6” f/6 Newtonian Reflector)
Eyepiece: 15mm Parks Gold Series Plössl (60x, 52′ TFoV)
Filter: None
Sketching Materials: #2 pencil, black ink, blending stump, 24# copy paper

Solar creatures?

Solar creatures? 

We sometimes imagine that clouds take on the shape of creatures.  These
prominences on the south limb of the sun on Sunday 8th April ’07 have been
similarly likened to a firebird, an ostrich, a wasp and a feeding spider.
When actually trying to sketch prominences it is better not to imagine such
things or else the drawings will tend to drift irresistibly towards the
imagined beasts!

These prominences were in any case very difficult to render.   They were
changing literally from minute to minute and were also ‘upside down’ in the
eyepiece.   The changes were so great that I started to wonder whether I had
got their structure at all correct but later comparison with images taken at
about the same time were reassuring.

Observed from England through a single stacked SolarMax60 H-alpha ‘scope at
50-80X.   There were varying amounts of high altitude cirrus haze but some
moments of high contrast clarity and atmospheric steadiness.   Sketches were
made large on A4 Canford black cartridge paper using white Derwent Studio
and Derwent Watercolour pencils, the latter dry.   Coloration was done in
Photoshop, this was the only modification made to the sketches after leaving
the eyepiece.

Les Cowley

Lunar luminaries

2006 07 07

Lansberg/Gamma and Delta

“Wednesday night (Thursday for UT), was a practice session for imaging with my
Rebel.  I finally bought a t-ring adaptor during a star party a few weeks ago and
had some fun playing with the new toy. The guys in the DSLR forum are giving me some
great pointers.  Feels very strange entering that realm, but I have a feeling it
will compliment the sketching well for my observations.  Plus gives me yet another
way to enjoy this hobby to the fullest!

It was then time to put the camera away and dig out my sketch kit.  Paul, being the
thoughtful husband that he is, bought Tom L’s binoviewers for me last month.  Tom,
if you’re reading this, I absolutely LOVE them!  Wow!  Thank you both so much!!!
I’ve been having a lot of fun with black Strathmore paper and Conte’ crayons for my
solar work, so with Rich in mind, I got up the nerve to try my first lunar sketch
with this media. Lansberg and the surrounding craters were my main targets that
night.  I explored the terminator, tried to count craterlets in Plato, and admired
Copernicus (and was tempted to try it again, as the last time I tried to sketch that
beauty, my sketch was cut short and it was never completed).

Lansberg is from the Imbrian period and is about 41km.  The central mountains stuck
out like two eyeballs in a dark room and I was pleased to see some terracing.  All
the little craterlets around Lansberg belong to it with Kunowsky D being the
exception to the NW.  Reinhold is trying to slip into the scene to the NE, but got
its toe stuck in the door.  Montes Riphaeus was very dramatic, or at least compared
to the rest of the scene in that area.


After a great day today, which included solar observing (boy, that sun feels
great!), I set up with the binoviewers again tonight.  Although seeing was poor, I
went ahead and bumped up magnification with 8mm TV Plossls (love that EP so much, I
had to get another one!).  It was good enough to support the level of detail needed
to observe domes.  Had I wanted to jump into a few complex craters, I believe a 20mm
would have been best.  So, domes it was and why not a pair?  Mons Gruithuisen Delta
and Gamma were flagging me down and I just could not resist. 

Gruithuisen Domes Delta and Gamma

They are also from the Imbrian period and close to 20km each.  Looking at VMA, Delta
is classified as a mountain and Gamma is a dome.  Rukl calls both of them a domelike
mountain massif.  Hmmm, let’s see what Chuck Woods has to say about them.  Aha!  He
calls them domes, most likely formed of silicic volcanic rocks.  For more reading on
this, see The Modern Moon, page 37.  I would love to be one of the geologists that
Chuck suggests may someday bang on the domes with their rock hammers to see what
they are made of.
It was a bit disappointing that I didn’t see the summit crater on Gamma, but there
was an obvious darkened area on the western top portion of it.  I loved buzzing
around in the all the little dips and valleys to the north of it, though.  The
little raised line between Gamma and Gruithuisen K looked like a pea pod. Isn’t the
lava covered floor beautiful in that region?”
Sketches done with black Strathmore Artagain paper and white Conte’ crayons

Erika Rix

Zanesville, Ohio

Diamonds at the feet of the twins

Diamonds at the feet of the twins 

Open cluster M35 in the constellation Gemini 

Here’s my first observation with the SkyWatcher 102/500. This 102mm rich field scope gives a whole new perspective on deep-sky objects. With a SP 26mm EP, I get a whopping 2.7 degrees field of view at a power of x19. I hope you like the view.

Date : March 8, 2007
Time : 20.30 UT
Seeing :2.5/5
Transp. 3/5

Digital sketch made with Photopaint, based on a raw pencil sketch made behind the EP.
N down, W left orientation.
Rony De Laet

http://www.geocities.com/rodelaet, my personal website.

A daisy in the field

AR 756 Sunspot sequence

What a difference a day makes

This pair of sunspot drawings hails from the tail end of activity of the current solar cycle. The weekend of May 1st and 2nd 2005 consisted of two ‘blue sky’ days here in southern England, and I had the chance to observe and sketch the Sun in white light on both of them, recording the intriguing changes to AR 756 that occurred in just over 19 hours. I used graphite pencil on white cartridge paper, my favourite medium for this kind of target. For each sketch I drew the umbra first, then added the penumbral region with lighter pencil strokes drawn from the umbra outwards, with the pores being added last. The seeing conditions were very steady and not a breath of wind was to be had while I spent a happy (but very hot!) hour in front of the eyepiece each day.

Sally Russell

Sketch details: 

Date: 1st and 2nd May  2005   

Time: 14.20-15.30 UT & 10.05-11.15 UT respectively 

Equipment: 105mm AstroPhysics APO, 9mm TV Nagler, 2 x Barlow (mag x135),

Kendrick white light filter

Additional accessories: Large brimmed straw hat and a cold drink!                                                     

Medium: Graphite pencil on white cartridge paper                                                                                     

Each image size: approx. 1.5″ x 1.5″

Between Serenity and Tranquility

Plinius and Dawes 

Craters Plinius and Dawes
After more than 23 days of very cold, cloudy, winter weather an approaching warm front got me out under the moon and stars on this clear, transparent night of good seeing. I centered the telescope field of view on craters Plinius and Dawes near the lunar terminator. This is the region I selected for my sketching. Plinius is the largest (43km) crater in the sketch. Its central peak and irregular, cratered floor are hidden in darkness but a hint of its terraced walls can be seen on the illuminated inner west margin. Further to the west the peaks near Promontorium Archeruia are catching the rising sunrays. About 55 km to the south of Plinius is crater Ross, a 26 km diameter crater identified only by its sunlit rim. This crater rests in the Sea of Tranquility. To the northeast of Plinius near the edge of the Sea of Serenity is the 19 km crater Dawes, its floor mostly in shadow. Directly to the north of Plinius the rilles of Plinius were clearly visible. In addition a small part of Dorsum Nicol is also seen. All of these features are positioned on the dark colored lavas at the boundary between the two above mentioned seas. The grazing sunlight helped to enhance the changes in topography.

Frank McCabe
  Sketch details:
  For this sketch I used: black Strathmore 400 Artagain paper 9”x12”, white and
  black Conte’ pastel pencils and a soft leather blending stump.
  Telescope: 10 inch f/ 5.7 Dobsonian and 6 mm eyepiece
  Date: 2-23-2007 1:05-1:45 UT
  Temperature: 0C ( 32F)
  Clear, calm
  Seeing:  Antoniadi  II
  Colongitude 339 degrees
  Lunation 5.4 days
  Illumination 35.7%

Fountains of the Sun

Prom 1Prom 2Prom 3

Ever-changing Proms 

AR949 was not very apparent, but there may have been a hint of a few pores towards the center of the disk, slightly north of the “equator”.  There were two long slender patches of plage near a fairly long (maybe 20 deg) filament in this region.

Along the limb, I noted 7 areas of prominences, with some scattered jets of “baby” proms spiking out here and there.  Of the 7 areas, I initially concentrated on two, position angles of approximately 240 and 50 degrees.  The area at the NE was very faint at first.  I adjusted the front etalon to create more contrast.  But come to find out, yes it was faint, but the sweet spot of this 60mm Maxscope seems to be just SW of center.  I heard that these Maxscopes don’t have a sweet spot, but there is an obvious difference in the contrast depending on where your target is in the FOV with this scope.  Still, it’s a beauty of a scope and I still can’t believe my good fortune in acquiring it.

The prominence to the SW was very sharp and prominent.  Still, you can see the slight changes over a 30 minute time frame, making it an amazing site to behold. Like the Moon, you can’t spend a lot of time rendering the view.  The terminator on the Moon changes before your eyes.  Well I feel the Sun is even more dynamic, and the sketches last only minutes before the shapes take a different form.

Getting back to the NE prom, it was very fibrous and to me was lovelier than the SW area.  Again, the changes are noted in a 30 minute time frame.

What ended up being my la proéminence du jour was a patch of nearly lunar terminator looking proms on the western limb.  When the session began, this area was plain, with only a few little spikes with a finger pointing north.  But about 45 minutes later, made me feel like I was observing the Moon again, just like it did the day I sketched this prominence.

AR946 had comma shaped plage surrounding the 2 sunspots within connected by a darker
strand.  There was a filament about the same size located to the southern region of
the disk as well as plage just inside the limb about 30 degrees from the prominence
at PA 70 degrees.

2007 04 02, 1900-2000 UT
Zanesville, Ohio
Internally Double stacked Maxscope 60mm with 8mm TV plossl.
Seeing average with moments of heavy quivering.                                                                                              Transparency poor.
Temps 72 °F / 22.2 °C
Winds from West at 16 mph with gusts up to 28 mph, scattered clouds
31% Humidity                                                                                                                                              Sketches were done with black Strathmore paper and colored Conte’ crayons.

Erika Rix

Busy bees

The Praesepe, M44

Praesepe, Messier 44

Here is an encounter with an old friend, M44, visited with a new scope. The Skywatcher is a nice low power scope to enjoy large objects, like in this case : Praesepe. I tried to sketch the overall low power view, combined with the fainter stars visible at 33x. The higher power allowed me to separate ADS 6921 (in the Northern arm of the V shape) into four components : mag 6.4,7.6,9.2,10.4. You might need to squeeze your eyes to notice the fourth star in the sketch. When the sketch was finished, I counted (just for fun) the numbers of stars I’ve drawn. The number is 147.

Rony De Laet
http://www.geocities.com/rodelaet, my personal website.

Date : March 14, 2007
Time : 21.30UT
Scope : Skywatcher 102/500
Eyepieces : TV SP 40mm, SP 25 mm, SP 15 mm
Power : 12.5x to 33x
FOV: 3.3°
Filter : none
Seeing : 2.5/5
Transp. : 2/5
Sketch Orientation : N down, W left.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.

In the belly of the whale

Messier 77

Here is my sketch of Messier 77 (Seyfert Galaxy). It was done on January 19, 2007, with a 12″ Lightbridge. The seeing and transparency were both average. The medium I used was Graphite pencil.

Sal Grasso

Messier 77 is a beautiful face on spiral that lies is the midst of a small group of galaxies in the southern constellation of Cetus. It has the distinction of being one of the most distant of Messier’s famous non comet inventory at about 60 million light years away. This sprawling city of stars is fully 100,000 light years wide and appears to harbor a supermassive blackhole that is currently energizing an accretion disc of infalling dust and gas. Studies with the Chandra Observatory show a beam of X-Ray radiation that is aligned along an axis passing through the galaxy’s core. The presumed engine is the dynamo action of the accretion disc; hot plasmas race around the hole at close to the speed of light, creating magnetic fields that confine and eject matter along the rotation axes of the monsterous gravitational maw.

Entrance to a frozen Hell

Eratosthenes entrance to a frozen Hell

There was a very thick mist that night, and the moon was hardly visible behind the clouds. I  put the scope outside with no intent for observing, as I wanted to adjust a new home made focuser. It was a very pleasing surprise to discover that there was absolutely no turbulence at all on the Moon.
Despite the thick clouds, the light and contrasts were still strong, and everything was frozen, no movement at all. I jumped on my pencils, and made a draft of Eratosthenes, one of my favorite craters on the Moon, maybe my favorite. I like the long and thin design of the Apennine mountains terminating like a lyra, with that black and strange hole, just at the limit of infinite darkness.

Pierre Desvaux

– Medium used: White Conté on black Canson paper
– Telescope: Home made 16″ Dobson, Nagler 12, barlow 2X Celestron
– Date: December 2006
– Place: Blanzy, Bourgogne, France