Category: cluster

The Box in Coma Berenices

Hickson 61

Hickson 61
Sketch and Commentary by Bill Ferris
Move mouse over sketch to see labels.

Hickson 61: Galaxy Cluster (Coma Berenices)
RA: 12h 12.3m / DEC: +29º 10′.8
Instrument: 18-inch Obsession

This quartet can be found in northwestern Coma Berenices. 4.3 magnitude Gamma (15) Comae Berenices shines as a naked eye landmark about 3 degrees to the east. My sketch presents a 199X view in the 18-inch Obsession. The brightest of the four galaxies is NGC 4169, also known as Hickson 61A. This 12.2 magnitude S0-type galaxy covers a 2′ by 1′ area and is aligned northwest to southeast. It is westernmost of the four, becomes gradually brighter towards the middle and displays a stellar core. The slender galaxy 2′ to the northeast is Hickson 61B. Hickson 61B is a 13.6 (B) magnitude spiral seen nearly edge-on. It covers a 5′ by 0′.7 area in my drawing, tapers in brightness towards the ends and is aligned northwest to southeast. Also known as NGC 4173, this galaxy’s ragged form shows no hint of stellaring at the core. The other edge-on spiral in the field is Hickson 61C, listed in Dreyer as NGC 4175. It’s a 14.2 (B) magnitude object covering a 1′.8 by 0′.4 area. NGC 4175 features a bright mid-section and has nearly the same position angle as its sibling to the northwest. Finally, NGC 4174 equals Hickson 61D. At 14.3 magnitude in the blue and 1′ by 0′.5 in size, this stellar metropolis is the smallest and faintest of the bunch. Aligned northeast to southwest, NGC 4174 features a faintly stellar core within a surrounding disk of even brightness.

Markarian’s Chain

Markarian’s Chain

Markarian’s Chain
Sketch by Eric Graff

This beautiful chain of island universes lies some 70 million light years away, at the heart of the Virgo Cluster of Galaxies. The cluster contains more than 2000 galaxies, about 1 percent of which are visible in Eric Graff’s sketch above. Eric created this mosaic while observing with his 6″ Newtonian reflector.

Five Stellar Gothams

Hickson 58

Hickson 58
By Bill Ferris

Move mouse over image to view labels. Click the image for a larger version.

This sketch of the galaxy cluster, Hickson 58 was made by Bill Ferris using his 18 inch Obsession. He used a 12 mm Nagler T4, which provides a magnification of 199X when mated with the TeleVue Paracorr. Following are Bill’s notes on the observation:

Hickson 58 is populated by five stellar gothams ranging in brightness from 13.9 to 15.4 magnitude; all in the blue. Centered within the group is NGC 3822, a 14.1 (B) magnitude galaxy also known at Hickson 58A. Its stellar core is embedded within a 1′.5 by 1′ oval nebulosity of even brightness and aligned north to south. About 3′ to the east, Hickson 58B emerges from the darkness. This 13.9 (B) magnitude barred spiral is better known as NGC 3825 and, as with its neighbors, features a stellar core. The surrounding 2′.5 by 1′.5 nebulosity becomes gradually brighter toward the middle. NGC 3825 is flanked to the southwest by a 12th magnitude star and to the northeast by a 13th magnitude ember. About 5′ west of NGC 3822, the 14.3 (B) magnitude oval form of NGC 3817 (Hickson 58C) comes into view. This barred spiral displays a stellar core within a delicate 1′.4 by 1′, east to west, oval. A 14th magnitude GSC star stands entry 1′.5 to the west. The faint pairing north of center in my sketch, which renders a 199X view in the 18-inch, are Hicksons 58D and 58E. The 14.8 (B) magnitude elliptical galaxy NGC 3819 lies 4′.6 north of NGC 3822. This tiny, 0′.8 by 0′.5 galaxy is Hickson 58D. Another 2′ to the north stands Hickson 58E. This 15.4 (B) magnitude galaxy is also known as NGC 3820. It is similar in size to NGC 3819 and has the same north-south alignment.

The original entry for this observation and sketch can be found at Bill’s website:Cosmic Voyage: Hickson 58Additional detailed information on the cluster may also be found at the WikiSky entry for NGC 3822 (Hickson 58A)

Three Fuzzy Friends

M96, M105 and NGC 3384

M96, M105 and NGC 3384
By Jeremy Perez

M96, M105 and NGC 3384

These three galaxies were kind enough to fit in the field of view together. The two galaxies on the north side, M105 and NGC 3384 appeared about 10′ apart, nucleus to nucleus. Their nucleii were softly stellar in appearance. M105 appeared basically circular and the brighter of the two, while NGC 3384 was elongated north-northeast to south-southwest. M96 was about 50′ to the south. It was the largest and brightest of the three galaxies, elongated northwest to southeast. It didn’t have the same stellar nucleus as the other two, it was a bright nucleus, but not as concentrated. Observing all three galaxies at 120X didn’t expose more detail, mostly just verified what I had already seen at 37X.

Factoids:
M96 is a type Sa spiral galaxy that is the brightest of the Leo 1 group of galaxies, which includes M95 and M105 as well as other fainter galaxies. It lies about 38 million light years away and it’s bright inner portion extends about 66,000 light years in diameter. It has a fainter outer ring which extend that diameter to about 100,000 light years. The inner disk is composed of an old population of yellow stars. The galaxy contains a significant amount of dust and blue knots of star forming regions. It was discovered by Pierre Mechain in 1781 and thus cataloged by Charles Messier a few days later.

M105 is an E1 elliptical galaxy that is a member of this same galaxy group and so is also about 38 million light years distant. It is often studied as a standard representative of elliptical galaxies. A Hubble Space Telescope survey of the galaxy has shown it to contain a massive central object weighing in at 50 million solar masses. M105 is moving away from us at 752 km/sec. It was discovered by Pierre Mechain a few days after M96, but for some reason wasn’t included in Charles Messier’s catalog. It was added as M105 in 1947 by Helen Sawyer Hogg along with M106 and M107.

NGC 3384 is an E7 elliptical galaxy that contains what appears to be a central bar. It also appears to be a member of the Leo 1 galaxy group.

Subject M96 (NGC 3368), M105 (NGC ), NGC 3384
Classification Spiral and Eliptical Galaxies
Position* Leo:
M96: [RA: 10:46.8 / Dec: +11:49]
M105: [RA: 10:47.8 / Dec: +12:35]
NGC 3384: [RA: 10:48.3 / Dec: +12:38]
Size* M96: 7.1′ x 5.1′ / M105: 4.5′ x 4.0′ / NGC 3384: 5.9′ x 2.6′
Brightness* M96: 9.2 / M105: 9.3 / NGC 3384: 10.0
Date/Time February 4, 2005 – 1:45 AM
(February 4, 2005 – 08:45 UT)
Observing Loc. Flagstaff, AZ – Home
Instrument Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag. 32 mm (37X), 10 mm (120X)
Conditions Clear, 25?F
Seeing 3/10
Transparency Mag 5.2
Sources SEDS 
*Based on published data.

Surreal Juxtaposition

IC 1633 

IC 1633

Elliptical Galaxy (cD) in Phoenix

Parks Astrolight EQ6 • 6″ f/6 Newtonian Reflector
7.5mm Parks Gold Series Plössl • 120x, 26′ Field of View
11 October 2007 • 06:30-07:15 UT

IC 1633 is the antithesis of NGC 55. It is located 1° northeast of 3rd-magnitude Beta (β) Phoenicis, half the distance between that star and 5th-magnitude Nu (ν) Phe. Small, and faint, its feeble glow is best detected with averted vision. In the eyepiece it is completely featureless. In reality, IC 1633 is a gargantuan elliptical galaxy lurking in the heart of galaxy cluster Abell 2877  (of which it is by far the most prominent member). Its distance from Earth is estimated at 325 million light-years! That fact alone, made this observation worthwhile.

As I observed this pale mist of ancient photons (and futilely scanned the field for other cluster members – or even a few more field stars), IC 1633 became entangled in the fire-blackened boughs of an oak tree victimized by the 2003 Cedar Fire. On a whim (and growing a little bored with my fruitless search for anything else to add to my sketch) I hastily added the twisted limbs to the drawing, providing a surreal juxtaposition of objects near and far.

James Dunlop apparently discovered IC 1633 during the 1820’s from the Brisbane Observatory at Paramatta, New South Wales, Australia. As this object failed to appear in the NGC, we may presume it was one of the (many) objects discovered by Dunlop that could not be recovered by John Herschel. In the Second Index Catalogue, DeLisle Stewart and Lewis Swift share credit for the discovery (or “re-discovery”) of IC 1633.

Extreme deep sky observing

Arp 263 

 Arp 263 Pencil on white paper, inverted in Photoshop. I was at the 2006 Texas
Star Party and using a 30″ Dobsonian for this observation. This type of observing
really sums up an event like TSP for me – extreme deep sky observing under superb
conditions. What I really love about this observation was all the faint galaxies
also visible in the field.

  Date: 28 April 2006
  Instrument: 30″ Starmaster Dobsonian, driven
  Magnification: Not known
  Location: Texas Star Party, Prude Ranch, Ft Davis, TX, USA
  Conditions: Excellent, if a bit windy. Totally cloudless
  NELM: Greater than 7.0

  Notes: A nice field full of galaxies. Arp 263 (NGC 3229) is the brightest and most
obvious object in this field, and there are lots of smaller, fainter galaxies as
well, all with CGCG and MCG designations. The most obvious thing about Arp 263 is
the arm of material stretching away from it. Nice, and one of my favourite views
from TSP 2006.

Faith Jordan
Isle of Wight, England

Thinking outside the circle

Virgo Cluster

Virgo Cluster panorama

This sketch was made from McDonald Observatory’s parking lot near Fort
Davis, Texas, during a trip down south. I used a 14.5″ Dobsonian and 26mm
Plossl eyepiece, and graphite on paper (reversed in Photoshop for effect). I
had prepared circles for sketching, but we ran into a streak of 6 clear
nights and I ran out, and had left my circle template back in Winnipeg. I
decided to just start sketching without the boundary of an eyepiece filed
and see what happened.  I really like the wide-field effect of not using an
eyepiece FOV circle – especially for clusters that need to be seen in
context.

Scott Young

Galactic fetters

Markarian’s Chain of Galaxies

Markarian’s Chain of galaxies

Sketch was made on copy machine paper, A4 in size, with regular graphite pencil and blending stump. Conditions were good, transparency was excellent , limiting magnitude was 5.70 but seeing wasn’t that great. I used 8″ F6 dobson and 10.5mm Baader Hyperion Eyepiece. Magnification was 114x.

Vedran Vrhovac

70 million light years away, the sprawling Virgo Cluster is home to perhaps thousands of galaxies. In fact the Virgo cluster, despite it’s great distance, subtends an angle of about five full degrees in our sky, making it ten times larger than the angle the Moon subtends. Markarian’s Chain, beautifully rendered by Vedran, includes M84, M86 and M88 along with a host of smaller elliptical, spiral and irregular galaxies. Studies indicate that seven of the galaxies in the Chain actually move together at the same relative velocity.