All Arps so far
In this topic I am leaving the traditional “eyepiece view” and provide a crop of the original Arp sketches that I have done so far. Therefore, more attention to detail can be achieved. Additionally there is an “inverted color” and enhanced inset with remarks about the Arp details seen (or missed). Next to each “Challenge” there’s a “Y” if all features could be seen or a “N” if none of them were observed. A “P” indicates that the mentioned features were partially visilble.
All sketches have been corrected to show North ↑ up and West → right.
I will try to sketch every Arp peculiar galaxy with my 16″ scopes from the darkest location possible, preferably from a site with a minimum SQM reading of 21.4. But on occasion I’ll settle for as low as 21.1 (near my home) or go as high as 21.8 (La Palma).
A 16 inch telescope may seem quite large for general amateur astronomy. However, for observing the peculiar features of the Arp galaxies it is rather small and it is therefore that many of the features will not be seen. But that’s OK… with this portfolio of sketches I will still try to provide a guide of what can be achieved with a “mere” 16 inch mirror.
More info about Halton Arp can be found on Wikipedia. Additionally, more info about observing the Arp galaxies can be found on Astroleague and Steve Gottlieb’s website. The complete Arp catalog can be reviewed and downloaded to Excel or Skysafari from Deepskylog, the tool that I use to prepare and log most of my observations.
Last but not least I have to mention one book that I used extensively in my search and analysis of all the Arps; it’s “The Arp Atlas Of Peculiar Galaxies” by Jeff Knipe and Dennis Webb, which contains a wealth of information and which I used as the main data source for my sketches below. It’s a great read and I can recommend it to anyone who is planning to observe the full catalog of 338 objects.
Good luck and above all: have fun!
Arp 1 – NGC 2857
mag 12.2, size 2.2′ x 2.2′
Challenge: Locate and trace both arms and disturbance in arm to SW of nucleus (N)
With AV a perfectly round stain is seen with no central brightening and very evenly illumination. No core or spiral structure is visible. A trapezoid of stars is nearby and in the same field a tiny galaxy (CGCG 238-051) is picked up.
Arp 2 – UGC 10310
mag 13.2, size 2.8′ x 2.2′
Challenge: Faint knotty arms starting about 1′ from core (N)
I did not succeed seeing this galaxy in my home country at SQM 21.6, but fortunately here on La Palma (with much better transparancy) I do see a very dim smear of light and I can see the elongated shape. No central brightening was observed and there are quite many very dim stars floating around.
Arp 4 – MCG-2-5-50 and companion
MCG-2-5-50: mag 13.7, size 2.8′ x 2.4′
MCG-2-5-50A: mag 14.9, size 0.6′ x 0.4′
Challenge: Ring of knots surrounding MCG-2-5-50 (N)
MCG-2-5-50A is seen immediately with AV, but MCG-2-5-50 could only just be suspected closely against its neighbour. MCG-2-5-50A is small and round, while MCG-2-5-50 is larger, also round and much softer, without a core.
Arp 5 – NGC 3664
NGC 3664: mag 13.2, size 2.0′ x 1.9′
NGC 3664A: mag 14.9, size 0.8′
Challenge: outer ring with knots and off-center bar (N)
A bit of a deception because it’s not really bright (but can just be seen with direct vision). NGC 3664 has a bit a of a bent shape and is a bit brighter towards the center. With a lot of effort a spiral arm can be seen at the SW side and the galaxy is surrounded by a soft glow.
Arp 6 – NGC 2537, The Bearpaw
mag 12.3, size 1.7′ x 1.5′
Challenge: Horseshoe-shaped ring with a knotty bar inside (Y)
The first impression gives a bright, slightly oval galaxy with a bright knot on the NW rim. Increasing the magnification is rewarding: the galaxy starts to “glow” and the mottling is very apparent now. The horseshoe shaped ring is seen, composed of several brighter areas within the galaxy and vaguely the middle toe of the paw can be discerned as well. On the N rim a m15 star is visible with AV. A fine galaxy this Bearpaw!
Arp 8 – NGC 497
mag 13.0, size 2.1′ x 0.9′
Challenge: Split arm SE and bent arm NW (P)
Can just be seen with direct vision. This is an elongated galaxy with a brighter core zone. The bent arm at NW can’t be seen, but the arm at SE is obviously slightly bent.
Arp 9 – NGC 2523
mag 11.9, size 3.0′ x 1.8′
Challenge: The split arm (N)
Pretty bright galaxy with a well defined bar and core area. Around it is a soft and round glow. At times I feel that I can see some of the spiral structure, but it’s too dim to draw any of it. Near a somewhat bright m11.7 star.
Arp 13 – NGC 7448
mag 11.6, size 2.7′ x 1.2′
Challenge: Fading texture to the N and SE of nucleus (N)
This is a clear, bean-shaped galaxy with an obvious brightening towards the core. On the S tip very feebly appears one of the detached segments. NW of the galaxy a tripple star can be seen.
Arp 14 – NGC 7314
mag 10.9, size 4.6′ x 2.1′
Challenge: Two odd segments to N, disorganized spiral structure (N)
Large and smooth galaxy that is not noticeably brighter toward the core. Easily seen with direct vision as an oval glow. No additional details seen, apart from nearby galaxy NGC 7313, which is small (almost stellar) and only seen with AV.
Arp 16 – M66 (NGC 3627)
mag 9.7, size 9.1′ x 4.2′
Challenge: Asymmetry (Y)
Of course bright and large too, even a bit brighter than M65 and with more details too. The core is small (not stellar) and much brighter than the outer parts. With AV the shape appears as that of a rugby ball, including the pointy ends. Two spiral arms are visible. The bottom one (N) is the brightest and “hooked”, easily seen against a dark intrusion and ending in a patch of nebulosity. The S-arm is dimmer, but reaches out beyond the boundary of the galaxy. Halfway, at the bend of the arm, a knot is seen.
Arp 17 – UGC 3972, PGC 21685 & PGC 21693
PGC 21693: mag 14.6, size 1.1′ x 0.6′
PGC 21685: mag 16.0, size 0.3′ x 0.1′
Challenge: The detached segment and asymmetry (N)
This object consists of two galaxies: PGC 21685 and PGC 21693, but only the latter is seen with effort as a dim, round haze in between two stars. No central brightening or additional details can be seen. The two galaxies together have designation UGC 3972.
Arp 18 – NGC 4088
mag 10.5, size 5.8′ x 2.3′
Challenge: Trace the fainter arm, discern rich mottling (P)
A fine sight. A distinct galaxy with spiral structure easily seen. To the SE of the core a dark wedge can be observed with under it a bright arm. on the NW side this is visible too, but dimmer and in the opposite direction. To the NE a loose fragment is seen on the extention; the disrupted spiral arm. Nice!
Arp 22 – NGC 4027 and companion
NGC 4027: mag 11.7, size 3.2′ x 2.4′
NGC 4027A: mag 14.9, size 0.9′ x 0.6′
Challenge: 4027 arm and mottled nucleus; 4027A linear core (P)
This is a nice one with a thick spiral arm at the N side. The arm ends at a dim star. The galaxy shows without a doubt central brightening and has a stellar core that is not much brighter than the surrounding glow. At the S side the galaxy is a bit flatter. A bit remote, but in the same field, NGC 4027A can be seen with AV with effort.
Arp 23 – NGC 4618 and NGC 4625
NGC 4618: mag 11.2, size 4.2′ x 3.4′
NGC 4625: mag 12.9, size 2.2′ x 1.9′
Challenge: Large arm in each galaxy, 4625’s faint outer arm and companion (P)
Very beautiful and with lots of structure visible. The thick arm is immediately noticed and the start of this arm from the SE of the oval shaped core too. The core and arm are separated by a large, dark void. With effort, the arm can be traced to the N, but not all the way. To the E NGC 4625 can’t be missed with direct vision.
Arp 25 – NGC 2276
mag 11.4, size 2.8′ x 2.6′
Challenge: Mottling and tubular arm in NGC 2276 (P)
Arp 25 is a part of Arp 114 (including NGC 2300). NGC 2276 is large and very soft, without a visual core area. With effort, a slightly lighter patch can be seen on the W side. This is the heavy arm.
Arp 27 – NGC 3631
mag 10.4, size 5.0′ x 4.8′
Challenge: The one heavy arm, the absorption tubes, and the faint extension to the N (N)
Large face-on with visible spiral structure. It’s a large, round glow with in the center a bright and compact core. At the N and S side of the core dark lanes can be discerned, betraying the spiral arms. At the S side the arm is indeed visible, but on the N side it’s harder. E of the core, near the edge, a knot or a foreground star is seen. Nice!
Arp 28 – NGC 7678
mag 11.8, size 2.4′ x 1.7′
Challenge: Three arms, one of which is heavy (P)
Very soft and almost round galaxy (face-on) with a compact and somewhat brighter core area, nestled between three brighter stars (and one dimmer). With AV the thicker arm on the S can be seen, mainly because of the darker notch between the arm and the core.
Arp 29 – NGC 6946
mag 8.8, size 11.6′ x 9.9′
Challenge: Five arms (P)
Nicknamed “The Fireworks Galaxy” because of the many supernovae occuring. This is a large face-on with three obvious spiral arms varying in brightness and thickness. The core is small and only a tad brighter than the surrounding (dim) glow. Many foreground stars are visible, embellishing the already splendid view. Two H II knots can be recognized. The fourth arm (detached from the third) and fifth arm were not seen.
Arp 31 – IC 167
mag 13.6, size 2.6′ x 1.4′
Challenge: Irregularity in NW arm (N)
This galaxy is only seen with difficulty with AV. There is no clear core zone and the shape not completely round. Nearby galaxy NGC 694 is seen with ease.
Arp 33 – UGC 8613
mag 15.3, size 1.4′ x 0.6′
Challenge: All four VV components and the faint wisp to W (N)
Part of Arp 326, but this one has its own Arp designation. UGC 8613 can be seen elongated, but no structure is seen, it’s very dim.
Arp 37 – M77 (NGC 1068)
mag 8.9, size 7.1′ x 6.1′
Challenge: The highly textured arms and the knots on the ENE and SW arms. The faint amorphous outer arms (P)
Beautiful face-on galaxy. Extremely bright with stellar nucleus and oval shaped core around it. The outer envelope spans up till halfway a bright star. On the SE side a definite flattening can be seen, here the glow fades more abruptly into the sky background. Two dark lanes can be seen on the SE and NW side, close to the core zone. They give away two spiral arms which can be seen too (with effort), the SE one being the easiest. The start of both arms moving out from the core is a bit brighter. By observing this galaxy at length, you can just “taste” the spiral structure getting through. Fascinating object.
Arp 38 – NGC 6412
mag 11.7, size 2.5′ x 2.2′
Challenge: Northern component (N)
Face-on which appears perfectly round. The glow is very dim and soft. The stellar nucleus is only a bit brighter. A fairly bright star is seen on the S-side of the field. Northern component not visible.
Arp 46 – UGC 12665
mag 15, size 1.2′ x 0.9′
Challenge: Asymmetry and companion to NE and subtle line to the SE (N)
The Arp feature refers to the least brightest galaxy in this field: UGC 12665, but the companion can’t be seen. Instead, a mag 15.8 star can just be glimpsed in the same area. The galaxy itself is very dim and can only be seen with AV as a slightly elongated smudge. The other galaxy, UGC 12667, is brighter and can be seen with direct vision. It is elongated too and bends toward a nearby star.
Arp 56 – UGC 1432
mag 14.6, size 0.9′ x 0.6′
Challenge: Western arm and the knot at its end (N)
Very dim, only seen with AV as a smooth round glow without a pronounced core zone. The spiral arm and the knot at its remained invisible.
Arp 65 – NGC 91 (also NGC 90) and NGC 93
NGC 91: mag 13.6, size 3.0′ x 0.9′
NGC 93: mag 13.3, size 1.5′ x 1.0′
Challenge: All three companions off the ends of the arms (N)
Two galaxies at a large distance from each other. E is NGC 93 and is small, pretty bright, oval and with a distinct core area. The PA can be seen with ease. NGC 91 on the other side is a dim cloud and only seen with AV. No extra details were observed and certainly not the three companions.
Arp 68 – NGC 7757
mag 12.7, size 2.5′ x 1.8′
Challenge: Companion and straight N arm (N)
A dim, yet quite large glow, somewhat oval shaped. Can only be properly seen with AV at the end of two m13 stars. The companion was not seen. NGC 7756 nearby I did see, but this is actually a star.
Arp 75 – NGC 702 and companion
mag 13.3, size 1.6′ x 1.2′
Challenge: Companion and asymmetry (P)
This one is small, but pretty bright and with a stellar core. The companion can not be seen apart, but more as a comma shaped extension. With AV the galaxy is clearly stretched.
Arp 76 – M90 (NGC 4569) and IC 3583
M90: mag 10.3, size 9.7′ x 4.4′
IC 3583: mag 13.3, size 2.2′ x 1.1′
Challenge: Absorption structures near the core of M90, linear core structure of IC 3583 (N)
This one is really nice, even though the spiral structure is a bit difficult to follow. It’s seen as a thick cigar, but with AV the shape is more like a needle due to the outer glow that extends far beyond the galaxy. At the N side the easiest arm is visible; a nice curl with below it another (dimmer) arm. They both run down on the E side. At the SW side another spiral arm can be seen that extends a bit further to the S. The core is remarkably stellar and brighter than any star in the field. Above in the image IC 3583 can be seen as a streak of light, captured between 3 bright and a dim star.
Arp 77 – NGC 1097
NGC 1097: mag 9.2, size 12.7′ x 9.4′
NGC 1097A: mag 13.8, size 0.8′ x 0.5′
Challenge: Bright knots in the arms, nonspiral structure S of the companion and the jets beyond the Arp fields (N)
This is a large barred spiral and also very bright. The bar is easily seen and on both sides of the galaxy a spiral arm is observed. The one on the N side is brightest and clearly shows a wide curl. The patch on the tip is brighter and ends near a dim star. The S arm is not as bright and is closer to the galaxy’s body. Also here a patch of nebulosity is seen on the tip. The core is bright, oval shaped and a notch is suspected on the E side. The companion is there like an exclamation mark but is not showing additional detail. These two galaxies together provide for a very nice sight!
Arp 78 – NGC 772, NGC 770 and companions
NGC 770: mag 13.9, size 1.2′ x 0.8′
NGC 772: mag 10.3, size 7.3′ x 4.3′
Challenge: Asymmetric arms and E lobe of 772 (N)
Nice and bright couple. NGC 772 is large, oval shaped with a distinct core area. near the edge of the soft glow in the SE a somewhat brighter part of the spiral structure is visible. North of the core is a dark intrusion which gives the impression of a spiral arm moving out. This arm however is not seen. nearby NGC 770 is small, nearly round and has some brightening towards the center. Other companions and the E lobe are not seen.
Arp 80 – NGC 2633
mag 12.2, size 2.5′ x 1.6′
Challenge: Lumps on arm to N (N)
Bright galaxy with a stellar core. Easily seen with direct vision. From the core there are elongations visible in both directions. To the north it appears a bit longer, which gives the impression of an off center core. The W side is a bit sharper edged.
Arp 81 – NGC 6621 and NGC 6622
NGC 6621: mag 13.6, size 2.1′ x 0.8′
NGC 6622: mag 16.0, size 0.5′ x 0.4′
Challenge: Shape of the NE loop (N)
Compact pair with some nebulosity in between. Brightest and largest is NGC 6621 in the N, it can just be seen with direct vision. NGC 6622 to the S is smaller and quite dim, but it can be seen without much effort. On the SW there appears to be a notch in the nebulosity. The loop was not seen.
Arp 84 – NGC 5394 and NGC 5395
NGC 5394: mag 12.1, size 2.9′ x 1.5′
NGC 5395: mag 11.4, size 2.9′ x 1.6′
MAPS-NGP: mag 18.3, size 0.35′ x 0.1′
Challenge: 5395 asymmetrical arms and rich texture; 5394 wide spirals and arcs around nucleus; and the MAPS galaxy (P)
NGC 5395 is the largest and brightest part, with on top of it a loose segment and at the underside a curl that fades out to the N as a dim line. Above and completely separate is NGC 5394 and this is a pretty bright patch in a droplet shape. Nice pair!
Arp 85 – M51 (NGC 5194) and NGC 5195
M51: mag 8.4, size 10.3′ x 8.1′
NGC 5195: mag 10.5, size 5.8′ x 4.6′
Challenge: Spiral arms in 5194; The arm connecting NGC 5194 and NGC 5195; The two fainter wisps running NW and SE of NGC 5195; Absorption structures in each arm of 5194 (P)
The “Whirlpool Galaxy“, probably the most famous of all Arps and it provides a fantastic view. The (face-on) spiral structure is seen immediately with ease. The E and brightest inner arm appears “hooked”. The N and S outer arms are dim and only seen with AV. The W inner arm is clearly specked with a multitude of H II knots. A detached section of the core is visible on the NE side.
NGC 5195 shows a brighter core area than that of M51. The companion galaxy is pear-shaped and has a dark intrusion on the W side. Its bar is pointing to the centre of M51. Even though an arm is clearly stretching in the direction of M51’s outer N arm, the famous “bridge” is not seen.
Arp 86 – NGC 7752 and NGC 7753
NGC 7752: mag 14.3, size 0.8′ x 0.5′
NGC 7753: mag 12.0, size 3.3′ x 2.1′
Challenge: Arm between galaxies (N)
Here’s a nice pair. NGC 7753 is the mother galaxy and is (almost) face-on with a bright and soft core and a large surrounding glow. Somewhat further to the SW NGC 7752 can be seen with direct vision. It’s small, compact and equally bright as the core of 7753. It’s not round, but slightly oval shaped. The connection between the two galaxies can’t be seen, but a dark intrusion on the N of 7753’s core betrays a spiral arm departing towards a mag 15.6 star.
Arp 93 – NGC 7284 and NGC 7285
NGC 7284: mag 12.9, size 2.1′ x 1.8′
NGC 7285: mag 12.9, size 2.3′ x 1.3′
Challenge: Long, wide plume exiting to N and swinging all the way around to the S (N)
These two are moderately bright and can be seen separated with ease. NGC 7284 is the brightest of the two and appears as a round dot. NGC 7285 is a bit more smeared out and slightly less bright. The two are covered in a cloud of nebulosity.
Arp 94 – NGC 3226 and NGC 3227
NGC 3226: mag 12.3, size 3.2′ x 2.8′
NGC 3227: mag 11.1, size 5.4′ x 3.7′
Challenge: Spiral arms of NGC 3227, faint wisps NE and SW of 3227, NE plume off NGC 3226 (N)
Two very striking galaxies, easily visible. NGC 3226 is brighter and with a bright, non-stellar core. The galaxy appears round. NGC 3227 does have a stellar core which is moderately bright, around it is a large oval glow with a slightly bent shape.
Arp 96 – MCG+14-4-10 & 11
MCG+14-4-10: mag 15.5, size 0.9′ x 0.8′
MCG+14-4-11: mag 14.6, size 0.9′ x 0.9′
Challenge: Extended arms of MCG+14-4-10 (N)
Very faint couple, both only seen with AV as small smudges of light, of which MCG+14-4-10 with difficulty. A dim m15.5 star can be seen in between them. No arms or spiral structure seen.
Arp 98 – UGC 1095 and MCG+5-4-66
UGC 1095: mag 15.0, size 1.4′ x 0.5′
MCG+5-4-66: mag 16.0, size 0.3′
Challenge: The differing arms of MCG+5-4-66 (N)
This Arp duo is on the verge of visibility. Both are very small, round and only intermittently seen with AV. MCG+5-4-66 forms a triangle with two mag 14 stars and is just a tad easier to spot than UGC 1095. No details were seen. Very hard observation.
Arp 99 – NGC 7550 group, Hickson 93
NGC 7547: mag 14.7, size 1.1′ x 0.5′
NGC 7549: mag 13.7, size 2.8′ x 0.7′
NGC 7550: mag 12.2, size 1.4′ x 1.2′
Challenge: Connection not seen, but note difference in arm toward and away from E galaxy. Note also material between W spiral and E galaxy. (N)
Arp 99 is a part of Hickson 93 but counts only three galaxies. NGC 7550 is the brightest member of the group and also the largest. Appears perfectly round with a bit brighter core area. NGC 7549 is a pretty large and dim stain and is slightly oval. It points just past NGC 7550. NGC 7547 is the smallest and dimmest one. It’s clearly stretched (2:1) and it too points just past NGC 7550. The light is evenly distributed on the surface. The three galaxies form a nice view and are easy to see. Hickson members NGC 7553 and NGC 7558 were not observed during this session.
Arp 104 – NGC 5216 and NGC 5218
NGC 5216: mag 13.6, size 2.4′ x 1.8′
NGC 5218: mag 12.3, size 2.9′ x 1.6′
Challenge: Wisps E and W of 5218, SW of 5218 and connection (N)
Known as Keenan’s system. A bit of a deception. NGC 5218 is largest, somewhat oval and with a stretched core. NGC 5216 is round and with a brigher core than NGC 5218. The connection between the two galaxies is not observed.
Arp 109 – MCG+12-15-17 and -18
MCG+12-15-17: mag 15, size 1.2′ x 1.7′
MCG+12-15-18: mag 15, size 0.4′ x 0.4′
Challenge: Loop on -17 (N)
Four galaxies are seen, of which IC 1146 the only one with direct vision. MCG+12-15-20 is barely seen with AV and the two Arp galaxies can be seen well with AV, MCG+12-15-18 a bit brighter. Together they form an “L”. No details could be seen.
Arp 111 – NGC 5421 and companion
mag 13.4, size 1.6′ x 1.0′
Challenge: Elliptical loop on the bent arm (N)
This is a very small and weak duo and it’s a challenge to split both galaxies (I did not see the elliptical loop). At 362x this is successful where NGC 5421A is the largest and brightest of the two and NGC 5421B can only be glimpsed with AV. The two reside in an oval glow and are perpendicular to a mag 15 star. The companion however can not be seen.
Arp 112 – NGC 7805 and NGC 7806
NGC 7805: mag 13.3, size 1.2′ x 0.9′
NGC 7806: mag 14.3, size 1.1′ x 0.8′
MGC+5-1-26: mag 16.5, size 0.6′ x 0.2′
Challenge: N arm of NGC 7806 and asymmetry of MCG+5-1-26 (N)
NGC 7805 and NGC 7806 can readily be seen with direct vision. Both are rather small and appear round, although on close inspection NGC 7806 seems a bit stretched. Surprisingly, the neighbour galaxy MCG+05-1-26 can be glimpsed too with much effort. It’s extremely faint and the light of the small streak of light pulsates in and out with AV.
Arp 113 – NGC 67 – 72
NGC 67: mag 15.2, size 1.0′ x 0.7′
NGC 68: mag 14.5, size 1.2 x 1.1′
NGC 69: mag 15.8, size 0.9′ x 0.8′
NGC 70: mag 14.5, size 2.0′ x 1.6′
NGC 71: mag 14.8, size 1.5′ x 1.2′
NGC 72: mag 13.4, size 1.1′ x 1.0′
Challenge: Spiral structure in NGC 70 and NGC 72 (N)
A small area rich with galaxies. At low power a combined smudge of light can be seen, but at high power all galaxies can be separated. The brightest three are in the center and form a triangle between three stars. NGC 68, NGC 70 and NGC 71 are well visible with AV and appear similar in size, shape and brightness. At the SE of this group is a dimmer galaxy with a large surrounding glow. This is NGC 72 and is still pretty obvious with AV. E of it is NGC 72A, this one is stellar and can sometimes be seen with AV. W of it is another dim specimen; NGC 69. This one time can only be seen half of the time with AV. Lastly, there are two more difficult galaxies in line with NGC 70 and NGC 68. These are NGC 67 and NGC 67A. These are almost stellar and could only be discovered by use of a detailed chart. No additional details were seen in these eight galaxies in a single field.
Arp 114 – NGC 2300 and NGC 2276
NGC 2276: mag 11.4, size 2.8′ x 2.6′
NGC 2300: mag 12.1, size 2.8′ x 2.0′
Challenge: Mottling and tubular arm in NGC 2276
NGC 2276 and NGC 2300 form a very nice and contrasting pair. The difference between the two galaxies is big; NGC 2300 is bright, slightly oval and with a clear core area. NGC 2276 (Arp 25) is large and very soft, without a visual core area. With effort, a slightly lighter patch can be seen on the W side. This is the heavy arm.
Arp 116 – M60 (NGC 4649) and NGC 4647
M60: mag 9.8, size 7.4′ x 6.0′
NGC 4647: mag 11.9, size 2.9′ x 2.3′
Challenge: Absorption band on NGC 4647 away from M60 (N)
M60 is large, bright and almost perfectly round. There appears to be no visible interaction with the companion galaxy NGC 4647 although they are very close to each other (not in contact). NGC 4647 is softer than M60 and has a smaller core area.
Arp 118 – NGC 1143 and NGC 1144
NGC 1143 (or NGC 1141): mag 13.2, size 0.9′ x 0.8′
NGC 1144 (or NGC 1143): mag 12.9, size 1.1′ x 0.7′
Challenge: Knotty loops between the galaxies (N)
These two can be seen clearly. They are separated, but in a bed of nebulosity. NGC 1142 / 1144 is a tad brighter and both appear round.
Arp 120 – NGC 4435 and NGC 4438, Copeland’s Eyes in Markarian’s Chain
NGC 4435: mag 11.7, size 2.7′ x 2.0′
NGC 4438: mag 10.1, size 8.6′ x 3.2′
Challenge: In NGC 4438: Warped arm in a “wishbone” shape; absorption structure to the W of the nucleus; triple structure in the nucleus (N)
A very bright duo of galaxies within Markarian’s Chain. NGC 4435 is not very special; it’s oval shaped and with a bright (non-stellar) core. But NGC 4438 is the real showpiece. It’s a bit larger and more stretched in an “S” shape (mainly due to a curl on the S-side) and on both sides, pretty far away from the galaxy, two patches of nebulosity can be seen. From the tips of the “S” shape a tail appears to run to these patches and on the S-side this “river” can actually be seen. On the N-side the brain is trying to fill in the missing piece of light, but I need to be harsh on myself and admit that I do not actually see it there. Furthermore, a lot of dim suns are seen, often on the verge of detectibility, which adds beauty to the dramatic vista. What a wonderful couple!
Arp 123 – NGC 1888 and NGC 1889
NGC 1888: mag 12.0, size 3.5′ x 1.0′
NGC 1889: mag 14.1, size 0.6′
Challenge: Faint parallel feature on opposite side from S0 galaxy and the kink in the SE end (N)
A very nice pair. A small globe is seen directly against a needle shaped galaxy. The two are in contact and surrounded by a shell of nebulosity. it has the appearance of a UFO.
Arp 124 – NGC 6361 and companion
NGC 6361: mag 13.1, size 2.2′ x 0.6′
MCG+10-25-3
Challenge: Faint bridge between the galaxies (N)
This Arp consists of the long NGC 6361 and small companion. The main galaxy is seen easily with an 4:1 oval shape and a bit of a brightening towards the center. The companion is very tough, it blinks around 40% of the time as a small and round dot, just under (and not to confuse with) a m15.8 star. The bridge between the two galaxies is not visible.
Arp 127 – NGC 191 and IC 1563
NGC 191: mag 12.5; size 1.5′ x 1.2′
IC 1563: mag 13.6; size 0.8′ x 0.4′
Challenge: Faint arms in NGC 191 (N)
This one is small, but with a surprising appearance; Two galaxies and a (somewhat brigher) object are embedded in a nebulous area. This nebulosity is actually the fuzzy spiral structure of NGC 191, but it’s hard to tell how this is confined. IC 1563 is clearly oval shaped and about as bright as NGC 191. Between the two, in a triangle, is another bright object. It’s unclear if this is a star or a galaxy, but it does appear very stellar and soft at the same time. A high magnification is needed to separate both galaxies.
Arp 134 – M49 (NGC 4472)
M49: mag 9.3, size 10.2′ x 8.3′
UGC 7636: mag 14.8, size 1.1′ x 0.9′
Challenge: Detect the dwarf irregular galaxy UGC 7636 companion and detect any structure in it (N)
Messier 49 is a large and almost round elliptical, gradually brightening towards the blazing core. In the same field NGC 4467 is visible with AV, but not the fragment UGC 7636. A mag 9 star is close to M49, just touching the edge of it.
Arp 135 – NGC 1023 and NGC 1023A
NGC 1023: mag 9.3, size 8.8′ x 3.0′
NGC 1023A: mag 13.0, size 1.6′ x 1.4′
Challenge: NGC 1023A (Y)
The “Perseus Lenticular Galaxy“. Large and cigar-shaped with a bright and diffuse core. With effort the galaxy NGC 1023A can be seen by AV on the SE tip as a tine smudge just a tad brighter than the sky background. But one has to know where to look.
Arp 136 – NGC 5820 and companions
mag 12.5, size 1.7′ x 1.1′
Challenge: Extension (streamers) off the SE end of NGC 5820 (N)
Now almost in zenith. I use the 5mm to keep a bright double star out of the FOV. NGC 5820 is a bright oval with bright core and soft outer area. The streamers can not be seen, but this galaxy is surrounded by fragments of which one can be (barely) spotted with AV, which is a nice bonus. Closeby is another galaxy: NGC 5821, which is dim but quite large. No additional details can be spotted here.
Arp 137 – NGC 2914
mag 13.2, size 1.0′ x 0.7′
Challenge: Hook to N and the wisp to S (N)
Two Arps in a single view. Arp 137 (NGC 2914) and Arp 232 (NGC 2911). Both are seen with direct vision and without any recognition of further detail. NGC 2911 is largest, somewhat oval and has a bright core. I don’t see the dim star against it. NGC 2914 is a bit smaller and less bright, but I do see that the core is a bit brighter. Here I do see a dim star just outside the glow.
Arp 141 – UGC 3730
mag 13.2, size 2.8′ x 1.5′
Challenge: Faint southern ring (N)
UGC 3730 can be seen well with AV as a small and round smudge of light. The southern component is very hard, but can be seen blinking up from time to time; tiny and just set loose from the main component. The tail and ring are not seen.
Arp 142 – NGC 2936 and NGC 2937
NGC 2936: mag 13.9, size 2.1′ x 0.7′
NGC 2937: mag 14.6, size 0.7′ x 0.5′
Challenge: Absorption lane running the lenght of NGC 2936 and the MAC galaxy (N)
This is a strange one. Two tiny galaxies can be seen close to each other near a concentrated starfield. The influence on one another can be seen. NGC 2936 curls like a banana around NGC 2937. The latter is nothing more than a tiny dot, which is mostly seen with AV. The dim and small MAC 0937+0246 could not be spotted.
Arp 153 – NGC 5128
mag 6.8, size 25.9′ x 20.1′
Challenge: Oblong shape of galaxy, absorption texture, and hook at NW of absorption structure (P)
Centaurus A is large and therefore I choose the 10mm to give a nice overview of the area. The galaxy is composed of two halves, of which the S half is the smallest and brightest. There is clearly a star trapped inside it, but with AV two more dimmer ones can be seen. The upper half of the “hamburger” is flatter and wavy and extends a bit more on the W side. The two halves are separated by a majestic dust lane, a bit wider on the W side. It is at this side of the dustlane that a star is seen inside it, with a patch of nebulosity moving away from it to the E. Around the hamburger there is soft glow and the field of view is specked with a lot of dim stars, but also a few brighter ones. It takes quite a lot of time to draw all that I’m seeing here. Marvelous object!
Arp 158 – NGC 523
mag 13.5, size 2.5′ x 0.7′
Challenge: Faint ESE extension (N)
Strange object. Hard to see with direct vision as a (slightly bend) stretched galaxy with some central brightening. At both “tips” a knot can be seen. The W knot is brightest and stellar (like a dim star), while the E knot is larger, softer and can only be glimpsed with AV.
Arp 159 – NGC 4747
mag 12.4, size 3.5′ x 1.2′
Challenge: Irregular absorption structure SE along nucleus and plume to NE (N)
This is a dim galaxy but can just be seen with direct vision. Despite its dimness it’s a nice view because of its needle shape with an oval glow around it (not edged sharply). The core zone is stretched and not evenly brightened; it’s mottled and sometimes the loose core parts can be glimpsed (two or three). Tough observation, but nice.
Arp 162 – NGC 3414
mag 12.0, size 3.5′ x 2.6′
Challenge: Diagonal filament (Y)
Here’s a bright and quite large galaxy that appears round at first glance, with a very bright core and soft outer envelope. Observing with AV shows the diagonal filament fairly easy, like a needle sticking through it. This galaxy resides in a poor star region.
Arp 166 – NGC 750 and NGC 751
NGC 750: mag 12.9, size 1.7′ x 1.3′
NGC 751: mag 13.5, size 1.4′
Challenge: Three faint radial companions (N)
Two galaxies are visible in this Arp. Both can be seen and separated easily. The surrounding nebulosity has a droplet shape because there’s a small notch on the E side. On the N side the nebulosity is a bit broader. NGC 750 is the largest and brightest of the two, the core is round. NGC 751 is smaller and oval shaped, the PA can be followed. The companions were not seen.
Arp 167 – NGC 2672 and NGC 2673
NGC 2672: mag 12.7, size 3.0′ x 2.8′
NGC 2673: mag 14.4, size 1.2′
Challenge: Plume of 2673, curving from SE to E (N)
Two small galaxies not far from M44 that almost touch each other. 2672 (W) is larger, oval and can be seen with direct vision. The brightness gradually decreases towards the edges and W of it is a dim star. 2673 can only be seen with AV as a dim and round cloud.
Arp 168 – M32 (NGC 221)
mag 9.0, size 8.8′ x 6.5′
challenge: The plume (N)
Often overlooked while observing the great M31 nearby. No special detail can be seen. M32 is moderately large and slightly oval shaped. At high magnification the difference in brightness within the galaxies is notable and not equally decreasing towards the outer section; the core is almost stellar and the brightness remains high until 50% outwards, after which it drops significantly. The plume was not seen.
Arp 169 – NGC 7236 and NGC 7237
NGC 7236: mag 13.5; size 0.7′
NGC 7237: mag 15.0; size 0.7′
NGC 7237C: size 0.4′ x 0.3′
Challenge: Faint plumes (N)
NGC 7236 and NGC 7237 are clearly seen separated and are both small and round. NGC 7236 is brightest, but can’t quite be seen with direct vision. Centrally it’s a tad brighter. NGC 7237 is only seen with AV as a smooth glow. slightly further in the field PGC 214811 can be picked up with AV, appearing starlike.
Arp 170 – NGC 7578 group, Hickson 94
NGC 7578A: mag 14.4, size 1.4′ x 1.4′
NGC 7578B: mag 15.0, size 1.0′ x 1.0′
PGC 70936: mag 16.3, size 0.3′ x 0.2′
Challenge: Faint members of Hickson group, and counter-tail (P)
This is a very compact group of many galaxies, of which two are quite easily seen (with AV). NGC 7578A is in the center as a small and round glow, just a bit brighter than NGC 7578B SW of it, which shows a similar size and shape. In the extension of these two a mag 14 star is seen. Very close to this star PGC 70936 seems to blink now and then in and out of view as a very dim star, but it’s a doubtful observation. I did not observe any other members of the Hickson group, while 94C just a bit further away should not be a very big problem to see.
Arp 173 – UGC 9561
MCG+2-38-19: mag 15.6, size 1.2′ x 0.2′
MCG+2-38-20: mag 15.0, size 0.6′ x 0.4′
Challenge: The plume S of -19, and the smaller plume NW of -20 (N)
Two galaxies can be seen in a diamond shape with two stars. The brightest, MCG+2-38-20 is very dim, small and seen round with AV. MCG+2-38-19 is only seen with a lot of effort as a meaningless dot of light.
Arp 182 – NGC 7674 Group, Hickson 96
NGC 7674: mag 13.9, size 1.1′ x 1.0′
NGC 7675: mag 14.8, size 0.6′ x 0.5′
MCG+1-59-81: mag 16.1, size 0.4′ x 0.3′
PGC 71507: mag 17.1, size 0.2′ x 0.1′
Challenge: Long straight, very faint filament like bow wave from companion (N)
Compact group of four galaxies, of which three are visible. Also known as Hickson 96.
NGC 7674 is the largest and brightest member, brightening towards the core en with a large surrounding glow. No spiral structure is visible. A very small and dim galaxy is just next to it: MGC+1-59-81. This one is only seen with AV, but still set loose from its neighbour. NGC 7675 can just be seen with direct vision as a small oval, the PA can be seen. There is no brightening towards the core. PGC 71507 is out of reach for now, but should be possible from an even darker location.
Arp 184 – NGC 1961
mag 11, size 4.6′ x 3.0′
Challenge: The filaments (P)
Soft oval glow, just visible with direct sight. Hard to see spiral structure, but after longer observation the filament on the NE side is recognized. Also the nebulosity between the core and the dim star to the S seems a bit brighter, which make the shape of the galaxy look like a mushroom.
Arp 185 – NGC 6217
mag 11.2, size 3.0′ x 2.5′
Challenge: outer filaments (N)
Bright galaxy with stellar nucleus. The start of the N arm can be seen with AV, curling to the E. The S arm is more difficult. Only the start can be seen with AV, but the curl is dimmer and shorter than the N arm. The filaments are invisible.
Arp 181 – NGC 3212 and NGC 3215
NGC 3212: mag 14.0, size 1.1′ x 1.0′
NGC 3215: mag 13.1, size 1.1′ x 1.1′
Challenge: Westward filament in NGC 3212 (N)
Two tiny galaxies with a very small difference in brightness and size, NGC 3215 the best visible of both. Both visible with AV only and no influence on each other is seen. No spiral structure and filaments.
Arp 200 – NGC 1134
mag 12.1; size 2.5′ x 0.9′
Challenge: The asymmetry and emanations (N)
Clearly seen, oval and with some central brightening. A star is very close to it and on this side the galaxy looks flattened.
Arp 202 – NGC 2719 and NGC 2719A
NGC 2719: mag 14, size 1.3′ x 0.3′
NGC 2719A: mag 14, size 0.9′ x 0.6′
Challenge: Triple core of 2719A and the faint tail (N)
NGC 2719 can be seen directly as a needle pointing NW. Almost parallel to it is a smaller, dimmer and a bit broader galaxy: 2719A. It takes AV to clearly see it and to split the two galaxies.
Arp 209 – NGC 6052
mag 13, size 0.9′ x 0.7′
Challenge: Oblong core and line of knots (P)
Pretty dim galaxy and very small. The core is a bit brighter with around it a round glow. High magnification reveals a comma shape, as if the galaxy has a dent on one side.
Arp 210 – NGC 1569
mag 11, size 3.7′ x 1.8′
Challenge: Mottling and absorption structures at NW and SE (N)
This is a pretty bright galaxy and can be well seen with direct vision. It appears comet-like; the W side is longer and broader. The obvious core is placed a bit off-center and at the W side of the core a small knot can be detected, almost touching the core. Not sure if this is a foreground star or something different. High magnification is needed to see the “double core”.
Arp 212 – NGC 7625
mag 12.1, size 1.6′ x 1.5′
Challenge: Detect the absorption tubes (N)
Compact and bright galaxy, easily seen. The core is not stellair but gets brighter towards the center. A mag 6 star is just outside the field. The edge is soft, but appears flattened in the SE, this gives the galaxy a triangular shape. The absorption tubes were not seen.
Arp 213 – IC 356
mag 10.5, size 5.3′ x 3.9′
Challenge: The absorption lanes (N)
Pretty bright and large galaxy. The core is small and bright and from there the outer glow dissipates very softly into the sky background. The shape is slightly elongated and there’s a dim star on the NE edge. The absorption lanes are not seen.
Arp 214 – NGC 3718
mag 10.7, size 9.2′ x 4.4′
Challenge: Long tails N and S, absorption features nearer nucleus, the three “barbs” to the E, and the wide outer loops (P)
Unexpected showpiece. There is much to see; a large galaxy with a bright core zone and a dust lane crossing through it. The core can’t be split at this magnification though. To the S, the spiral structure is showing a cavity which makes this part of the galaxy look like a “flame”. To the N, the nebulosity makes a curl to the W and on the E side a dim star can just be discnerned. Looks like a ghost version of the famous Hamburger Galaxy.
Arp 215 – NGC 2782
mag 11.7, size 3.5′ x 2.6′
Challenge: Large faint halo with brighter area W of core and wing to E (N)
Bright galaxy that can be seen with ease. The shape is almost round, slightly oval en the PA is difficult to recognize. The 1/3 core area is very bright and appears almost stellar. At times, some of the brighter areas appear to surface, but it’s too uncertain to draw any of it.
Arp 216 – NGC 7679 and NGC 7682
NGC 7679: mag 12.9; size 1.4′ x 0.9′
NGC 7682: mag 14.1; size 1.2′ x 1.1′
Challenge: Loop and patches (N)
Two small galaxies. NGC 7679 is the brightest, with some brightening towards the core. It appears perfectly round. NGC 7682 is a bit more oval shaped, is dimmer, but can still be seen with direct vision. No further details are visible.
Arp 217 – NGC 3310
mag 10.8, size 3.3′ x 3.0′
Challenge: Knots N of nucleus, arcs NW and SW, jet piercing NW arc (N)
This one is small and has a somewhat square shape. It shows strong mottling (like a bright “fuzzball”). During the sketching process a small loose segment catches my attention just E of the galaxy. A nice bonus, because I don’t see any of the other features. However, I can’t find any information on the segment so it could have been only in my imagination.
Arp 221 – MCG-2-25-6 and companions
MCG-2-25-6: mag 14, size 0.7′ x 0.6′
MAC 0936-1120: mag 18, size 0.4′ x 0.3′
W companion is mag 16
Challenge: Detect faint extension S and arm NE (N)
This is a really tight group. The core is just visible with direct vision of MCG-2-25-6. The tiny companion (that does not hold its own designation) is hard to see with AV. Together they form a triangle with a star. MAC 0936-1120 stays hidden, perhaps because a very bright star hinders the view.
Arp 222 – NGC 7727
mag 10.6, size 4.7′ x 3.6′
Challenge: Edges in the amorphous arms (N)
Fairly bright galaxy with obvious core zone. With AV the shape resembles that of a cradle, definitely not round. There is a noticeable ring of stars around the galaxy.
Arp 225 – NGC 2655
mag 10.1, size 4.9′ x 4.1′
Challenge: Faint amorphous arms and the texture in the SW part of the nucleus (N)
This is a bright galaxy with half core area and half soft outer halo. The galaxy is slightly oval shaped and the direction can just be guessed. No details are observed.
Arp 226 – NGC 7252
mag 11.4, size 3.8′ x 2.4′
Challenge: Long, almost straight, tails and the three loops that give the galaxy its nickname, the “Atoms for Peace” galaxy (N)
No details are seen, this galaxy appears pretty bright and round with an obvious core zone, almost stellar.
Arp 229 – NGC 507 and NGC 508
NGC 503: mag 15.1, size 0.3′
NGC 504: mag 14.3, size 1.7′ x 0.4′
NGC 507: mag 12.2, size 3.1′
NGC 508: mag 14.1, size 1.3′
IC1687: mag 13.7, size 0.5′ x 0.3′
CGCG 502-72: mag 14.5, size 0.5′ x 0.4′
Challenge: Faint outer halo of NGC 507 enveloping NGC 508 (N)
NGC 507 and NGC 508 are in the center of the group, pretty close to each other. The halo enveloping 508 is not visible. NGC 507 is brightest and largest, it’s round can be seen easily. NGC 508 just N of it is still pretty bright, small and round and with no central brightening. NW is NGC 503 and this one is very small, dim and can only be seen with AV. SW is NGC 504 and this is the second brightest of the group, to be seen with direct vision. The shape is round and compact. The protrusions are not observed. Two more dim galaxies enrich the field; MCG +05-04-048 (also CGCG 502-72) is very small en dim and can only be spotted with difficulty. IC 1687 was observed as a dim star, so it’s very small (only the core to be seen) but not too difficult with AV. This is a nice and rich Arp group.
Arp 232 – NGC 2911
mag 11.5, size 4.1′ x 3.2′
Challenge: Absorption lane running NW (N)
Two Arps in a single view. Arp 137 (NGC 2914) and Arp 232 (NGC 2911). Both are seen with direct vision and without any recognition of further detail. NGC 2911 is largest, somewhat oval and has a bright core. I don’t see the dim star against it. NGC 2914 is a bit smaller and less bright, but I do see that the core is a bit brighter. Here I do see a dim star just outside the glow.
Arp 235 – NGC 14
mag 12.7; size 2.8′ x 2.1′
Challenge: Two overlapping galaxies (N)
Very soft and oval shaped. Pretty large and seen with direct vision. It’s a bit more bright towards the center, but no further details are noticed.
Arp 240 – NGC 5257 and NGC 5258
NGC 5257: mag 12.9, size 1.8′ x 0.9′
NGC 5258: mag 12.9, size 1.7′ x 1.1′
Challenge: Arms of each galaxy and the bridge between them (N)
Arp 240 is a bright duo, consisting of NGC 5257 and NGC 5258. Both can be seen with direct vision and are of similar brightness. The core area is not much brighter in both. 5257 is round (a bit flattened) en 5258 appears a bit longer. At the latter, a dim star is seen on the N tip. The “bridge” connecting both galaxies is not seen.
Arp 242 – NGC 4676A and NGC 4676B
NGC 4676A: mag 14.7, size 2.3′ x 0.7′
NGC 4676B: mag 14.4, size 2.2′ x 0.8′
Challenge: Both tails, differing structure in cores (P)
“The Mice“. Very small and dim ovals, hard to locate. At first (direct) sight NGC 4676B appears brightest with a stellar core, but with AV NGC 4676A swells and the extension can be seen as a straight line (with much effort). The second tail remains invisible.
Arp 244 – NGC 4038/39, The Antennae
NGC 4038: mag 11.2, size 5.2′ x 3.1′
NGC 4039: mag 11.1, size 3.1′ x 1.6′
Challenge: The meandering “lasso” of knots around the nuclei and full extent of the antennae (P)
The “pacman” shape is immediately seen, where the largest and brightest half shows quite a lot of mottling. Some knots and brighter areas are noticed. Also in the smaller and dimmer half a brighter patch can be observed and this half is a bit softer defined. The “neck” is the narrowest part and from here I can see some nebulosity heading S. A bit further to the S I think I see a small part of the antennae, but it’s tremendously dim. In the 10mm the whole field is strewn with stars and of course this only adds to the already mesmerizing view.
Arp 253 – MCG-1-25-31 and -32
MCG-1-25-31: mag 15.0, size 1.3′ x 0.2′
MCG-1-25-32: mag 15.2, size 1.2′ x 0.4′
Challenge: Detect faint bridge connectiin the two components
Arriving at the correct location I don’t immediately see something, so I start with drawing the star field. Once I’m used to the view, I start to see blinking a very long, slightly bent “ribbon”. After long observation I start to see two core zones, but I don’t necessarily see the two galaxies separated. These are MCG-1-25-31 en -32 and a bit remote also MCG-1-25-33 is seen with AV as a dim, oval patch. This was a very hard observation.
Arp 254 – NGC 5917 and companions
NGC 5917: mag 14.5, size 1.5′ x 0.9′
MCG-1-39-3: mag 14.6, size 4.4′ x 0.6′
Challenge: The asymmetric arms in NGC 5917, and the full extent of the faint plumes N and S of MCG-1-39-3 (P)
NGC 5917 is round and can be seen with direct vision, but not terribly bright. It does appear to show some central brightening. With AV MCG-1-39-3 can be seen close to it and with effort the extensions in both directions can be seen as well.
Arp 261 – MCG-2-38-16 and -17
MCG-2-38-16: mag 13.4, size 3.0′ x 2.0′
MCG-2-38-17: mag 13.4, size 1.7′ x 0.9′
Challenge: Two bridges between -16 and -17 (N)
This is a tough one. MCG-2-38-16 can only be seen with effort with AV, but the needle shape (and direction) can be guessed. The companion MCG-2-38-17 remains hidden and thus also the two bridges that are supposed to connect them. Unfortunately I did not pay attention to PGC 53943 nearby.
Arp 263 – NGC 3239
mag 11.4, size 5.0′ x 3.3′
Challenge: Knots, E hook plume, SW “spike” pointing SE (P)
Strange looking galaxy; more like a rectangular glow against a bright star. Two knots are visible within this glow, at the tips. One is bright and can be seen directly, the other one is smaller and dimmer and is only visible with AV. The “plumes” are not seen.
Arp 266 – NGC 4861
mag 13.2, size 4.0′ x 1.5′
Challenge: Knots and asymmetry
Strange looking galaxy; a large and long streak of light stretches between a star and a HII knot (both easily visible). The brain fills in the space between the star and knot, but careful examination shows that the galaxy does not quite reach the star. A little off-center a bulge can be seen in the core.
Arp 268 – UGC 4305, Holmberg II
mag 10.7, size 8.0′ x 6.3′
Challenge: Linear loop of emission regions (P)
Very dim, but large and roundish “stain” with a remarkable triangle of mag 12 stars at the foreground. Low surface brightness with no core zone, but an arc of nebulosity can be seen moving W from the three stars. This is one of the easier Holmberg galaxies, but could only be seen with AV.
Arp 269 – NGC 4485 and NGC 4490
NGC 4485: mag 12.3, size 2.3′ x 1.6′
NGC 4490: mag 10.2, size 6.3′ x 3.1′
Challenge: Knots, asymmetry and the tail E of NGC 4490 (P)
The “Cocoon Galaxy“. This famous duo in Canes Venatici is a real treat in the northern sky. It comprises two galaxies that have an obvious influence on each other. A lot of structure and irregularities can be seen; NGC 4490 is oval shaped and the largest and brightest of the two, with a distinct (mottled) core area and two spiral arms showing a long and flattened “S”. NGC 4485 has a curved “droplet” shape with a loose fragment on top.
A – The core of 4490; bright and mottled, shaped like a stretched “D” or “Δ”. On the SE and NW side two spiral arms are reaching outwards.
B – Slightly brighter part of the northern arm.
C – The SE arm, a bit brighter, thicker and shorter than the N one.
D – A brighter “patch” of nebulosity at the end of the N arm.
E – A streak of nebulosity, like an island, set loose from the galaxy and separated by a dark lane.
F – Dustlane? Or just an empty space between NGC 4490 and the “island”.
G – Suspicion of a dim star, or maybe a H II knot?
H – Fragment, set loose from NGC 4485.
I – NGC 4485; a droplet shaped galaxy, arching towards NGC 4490. The core is small and just a tiny bit brighter.
J – A mag 14.7 star, easily seen at the outer SE region of 4490, embedded in a darker notch.
Arp 270 – NGC 3395 and NGC 3396
NGC 3395: mag 12.2, size 2.1′ x 1.2′
NGC 3396: mag 12.6, size 3.1′ x 1.2′
Challenge: Many knots and arcing arm in 3395 (P)
Nice pair, close to each other at an almost right-angle. NGC 3396 is somewhat brighter and is seen as a 2:1 streak of light with the core area a bit brighter, surrounded by a fuzzy halo. NGC 3395 is a bit dimmer and more evenly illuminated. With AV the start of a spiral arm can be seen to the S. There ‘s a lot of space between the two galaxies.
Arp 271 – NGC 5426 and NGC 5427
NGC 5426: mag 12.7, size 3.0′ x 1.6′
NGC 5427: mag 12.0, size 2.8′ x 2.4′
Challenge: Bifurcated arm and connection between galaxies (N)
Pretty bright and even some spiral structure can be observed. Both galaxies are seen with direct vision, however NGC 5426 with some effort. NGC 5427 is larger, brighter and round and two spiral arms are visible. Between the two galaxies there is dark space with a dim star in it. The bridge between the two galaxies is invisible.
Arp 273 – UGC 1810 and UGC 1813
UGC 1810: mag 13.4, size 2.0′ x 1.3′
UGC 1813: mag 15.1, size 1.5′ x 0.4′
Challenge: Asymmetrical arms in UGC 1810 (P)
Extremely hard observation. UGC 1810 is the brightest of the two, but despite that only seen with AV (mainly the core). However, the extension in both directions is suspected as well as the curving arm on the E side. UGC 1813 is only sometimes seen with AV as a small streak of light and is a threshold observation.
Arp 276 – NGC 935 and IC 1801
NGC 276: mag 13.6; size 1.7′ x 1.1′
IC 1801: mag 14.6; size 1.3′ x 0.6′
Challenge: Asymmetrical structure and knots in NGC 935 (N)
Small, but the galaxy is easily seen with a somewhat brighter core zone. Loose component IC 1801 is tough and difficult to see with AV. The couple is right next to a pretty bright (m10) star. On the S side of NGC 935 a dim m14 star is seen towards the galaxy seems to curl.
Arp 278 – NGC 7253A and NGC 7253B
NGC 7253A: mag 13.6, size 1.7′ x 0.7′
NGC 7253B: mag 14.4, size 1.6′ x 0.5′
Challenge: Asymmetry in the outer areas (N)
Nice but faint duo. NGC 7253A is brightest and is best seen with AV as a stretched galaxy with some central brightening. Almost perpendicular to it is NGC 7253B and is barely seen with AV as a streak of light. The two are “separated” by a dim double star (m15.4) which give this Arp a nice touch. A dark sky is mandatory.
Arp 279 – NGC 1253 and NGC 1253A
NGC 1253: mag 11.7, size 5.3′ x 2.3′
NGC 1253A: mag 14.4, size 1.3′ x 0.8′
Challenge: Texture in both galaxies and the arcing arm to the W of NGC 1253A (P)
When the object sails into view I see a thick and grainy “cigar” in an interesting star field. E of the cigar there is a tiny puff of smoke, but it’s on the limit of visibility. In line and on the other side of the brightest star in the center NGC 1253A is seen quite easy with AV. The two galaxies form a nice appearance.
Arp 281 – NGC 4627 and NGC 4631
NGC 4627: mag 13.1, size 2.6′ x 1.8′
NGC 4631: mag 9.8, size 15.5′ x 2.7′
Challenge: Plumes N and S of NGC 4627; filamentary absorption structures throughout body of NGC 4631 (P)
This is “The Whale” or “Herring” galaxy and the resemblance is striking. The size of NGC 4631 is enormous and fills a great deal of the field. The core is not clearly defined but looks more as if snowballs have been thrown at it. The surface is highly mottled and absorption lanes can be suspected, running vertically through the center. NGC 4627 can just be seen with direct vision as a dim smudge. A bright star is located between it and the core of NGC 4631.
Arp 282 – NGC 169 and IC 1559
NGC 169: mag 12.4, size 2.7′ x 0.7′
IC 1559: mag 14.7, size 0.8′ x 0.4′
Challenge: The spirals in NGC 169 (N)
Two galaxies really close to one another, but seen separated. NGC 169 is stretched and dim, best seen with AV. IC 1559 is even dimmer, smaller and round. It’s nearly perpendicular to the NGC galaxy. A very bright mag 6.3 star adorns the field, but it complicates a good observation.
Arp 283 – NGC 2798 and NGC 2799
NGC 2798: mag 12.3, size 2.6′ x 1.0′
NGC 2799: mag 14.3, size 1.9′ x 0.5′
Challenge: Knots in 2799 and the faint arcing wisp to N of 2798 (N)
NGC 2798 is pretty bright with a round core area and a round haze around it. With AV NGC 2799 can be seen as well with a needle shape (difficult). No further details are observed.
Arp 284 – NGC 7714 and NGC 7715
NGC 7714: mag 12.5; size 2.2′ x 1.1′
NGC 7715: mag 14.5; size 2.6′ x 0.5′
Challenge: Detect the tails and counter-tails (N)
Two galaxies at quite a large distance from each other. No nebulosity seen between the two. NGC 7714 is clearly the brightest, round and with a bright and small core area. NGC 7715 is hard to see with AV, but is clearly linear with even brightness accross the surface. The very bright 16 Psc (m5.9) is in the same field of view and makes a proper observation of the galaxies difficult.
Arp 285 – NGC 2854 and NGC 2856
NGC 2854: mag 13.0, size 1.7′ x 0.6′
NGC 2856: mag 14.1, size 1.1′ x 0.5′
Challenge: Jet from core of NGC 2856, pointing away from NGC 2854, and spiral arms in 2854 (N)
These two galaxies are rather far apart and don’t seem to influence each other. Both can be seen (perpendicular) with direct vision. NGC 2856 is slightly broader, brighter and larger. No jet or spiral structure seen.
Arp 286 – NGC 5566 group
NGC 5560: mag 13.2, size 3.7′ x 0.7′
NGC 5566: mag 11.5, size 6.6′ x 2.2′
NGC 5569: mag 13.9, size 1.7′ x 1.4′
Challenge: Ring and split in NE arm of NGC 5566 (N)
This a very bright group, at least two of the three galaxies. NGC 5566 is most prominent and very bright with a slightly oval core. The weak outer part could not be seen. NGC 5560 is also quite apparent with direct vision and is seen as a fat stripe. NGC 5569 completes the group and is seen with difficulty with AV like a round stain without central brightening.
Arp 287 – NGC 2735 and NGC 2735A
NGC 2735: mag 13.3, size 1.2′ x 0.4′
NGC 2735A: mag 15.3, size 24″ x 12″
Challenge: NGC 2735A and the detached segment at PA 260° of NGC 2735 (P)
Two small galaxies, seen detached from each other. 2735 (W) is a stretched oval (3:1) with a brighter core area. E of it, almost in line, 2735A can sometimes be glimpsed as a round and small cloud. The surrounding star view is attractive; four bright stars adorn the field in a “Y” shape.
Arp 289 – NGC 3981
mag 12.1, size 5.3′ x 2.3′
Challenge: Asymmetry in main arms and one or more of the faint filaments (N)
NGC 3981 is a bit of an asymmetrical one. The mottled core area can be seen with direct vision, but with AV the extension is seen. The S-side is longest and appears to slightly bend near the tip. The N-side is shorter, but quite broad.
Arp 290 – IC 195 and IC 196
IC 195: mag 13.9, size 1.2′ x 0.6′
IC 196: mag 13.6, size 2.8′ x 1.4′
Challenge: Distorted arms at both ends of IC 196 (P)
Both galaxies are seen with direct vision and IC196 is showing some nice features; two patches and a slightly curved arm. With that at least a part of the challenge is accomplished. The pair resides in an attractive star field.
Arp 293 – NGC 6285 and NGC 6286
NGC 6285: mag 14.5, size 0.9′ x 0.5′
NGC 6286: mag 13.3, size 1.5′ x 1.4′
Challenge: Faint arc SE of NGC 6286 (N)
A weak duo, but they can just be seen with direct vision. NGC 6286 is the brightest and largest of the two. They seem to be pointing to a common center of gravity and reside in a rich star field. The faint arc is not seen.
Arp 298 – NGC 7469 and IC 5283
NGC 7469: mag 12.3; size 1.5′ x 1.1′
IC 5283: mag 14.8; size 0.8′ x 0.4′
Challenge: Wide spiral structure and asymmetry in companion
Two galaxies of which the very small NGC 7469 is brightest. The core is slightly oval shaped and almost looks like a planetary nebula. IC 5283 is harder and can only be seen with AV, but the shape is visible. Close to NGC 7469 are two stars, of which the dimmest is m15.9
Arp 300 – UGC 5028 and UGC 5029
UGC 5028: mag 14.3, size 0.7′ x 0.4′
UGC 5029: mag 13.4, size 1.6′ x 1.0′
Challenge: The asymetrical structure in both galaxies (N)
Two dim galaxies close to each other, but not touching. UGC 5028 can be seen with direct vision and is slighty oval shaped. UGC 5029 has more or less the same shape, but slightly different angle and can only be seen with AV. Around the two galaxies there appears to be a large “question mark” of dim stars.
Arp 305 – NGC 4016 and NGC 4017
NGC 4016: mag 13.8, size 1.5′ x 0.8′
NGC 4017: mag 13.0, size 0.3′ x 0.2′
Challenge: Weak filament between galaxies; loops in 4016 (N)
Nice duo with NGC 4016 as a dim and round galaxy, almost only visible with AV, but with a somewhat brighter core. NGC 4017 is a quite large, oval glow with an apparent bean shape. Best seen with AV, but brighter than NGC 4016.
Arp 307 – NGC 2872 and NGC 2874
NGC 2872: mag 12.9, size 2.1′ x 1.8′
NGC 2873: mag 15.3, size 0.6′ x 0.2′
NGC 2874: mag 13.4, size 2.4′ x 0.7′
Challenge: Spiral arm in NGC 2874 (P)
This one consists of main galaxies NGC 2872 and NGC 2874, where the first is the brightest and round with a bright core. NGC 2874 is supposed to show a spiral arm, but I only see a part of it at the end at the N-E tip. Close by, NGC 2873 can be seen with effort as a dim stain.
Arp 310 – IC 1259, VV101
IC 1259 (VV 101a): mag 15; size 0.8′ x 0.4′
IC 1259-1 (VV 101b): mag 15; size 0.3′ x 0.3′
Challenge: Full extent of material enveloping both galaxies (P)
Arp 311 – IC 1258 through IC 1260
IC 1258: mag 14.3; size 1.0′ x 0.8′
IC 1260: mag 15.7; size 0.6′
Challenge: Faint bridge between the Arp 310 pair and IC 1258 (N)
Arp 310 and Arp 311 are overlapping Arps and are in the same field of view, even at 362x.
Arp 310 is part of Arp 311 and consists of IC 1259 and the dimmer IC 1259-1 (VV 101b) right against it. On the other side a dim m15 star is visible. These 3 components are confined in just 30 arc seconds of space, so increasing magnification is key. This small group is the brightest of all objects in view.
At the SW of the field IC 1258 is seen as a weak knot with (also here) right against it a dim m15 star that appears a bit fluffy. this galaxy can be seen with direct vision, but it’s less bright than IC 1259. To the E the dimmest and smallest galaxy can be glimpsed: IC 1260. This one is almost stellar.
Nice group!
Arp 315 – NGC 2830 through NGC 2832 Galaxy group
NGC 2830: mag 15.3, size 1.3′ x 0.3′
NGC 2831: mag 14.7, size 1.4′
NGC 2832: mag 12.3, size 2.3′ x 1.9′
Challenge: Separate 2831 and 2832 (Y)
Five galaxies in one field of view, of which NGC 2825 and NGC 2834 are out of the Arp group. NGC 2830 is hard to see with AV, but the needle shape and PA can be observed. NGC 2831 is mainly visible with AV. it’s dim, small and has no obvious core area. it’s seen loose from NGC 2832. The latter is easily seen with a pretty bright core and soft halo around it. This is a nice and compact group.
Arp 316 – NGC 3193 group in Hickson 44 Galaxy group
NGC 3187: mag 13.9, size 3.0′ x 1.3′
NGC 3190: mag 12.1, size 4.4′ x 1.5′
NGC 3193: mag 11.8, size 3.0′ x 2.7′
Challenge: Spirals of NGC 3187 and SW companion. Dust lane in NGC 3190 (N)
Very nice group of three galaxies in the neck of Leo. I choose a low magnification to nicely frame the fourth Hickson galaxy too. 3193 is very bright, round and with a relatively large core area close to a brighter star. 3190 is stretched and the slightly oval centre is a bit brighter. It is about as eyecatching as 3193. That can’t be said of 3187, which is only visible with AV. It has a thick needle shape too, pointing in exactly the same direction as 3190. Lastly, at some distance 3185 is seen as an almost round stain of nebulosity with a hardly brighter core. It can be seen with direct vision. The four galaxies reside in a nice starfield with big differences in magnitude.
Arp 317 – The Leo Triplet; M65, M66 and NGC 3628
M65: mag 10.3, size 9.8′ x 2.9′
M66: mag 9.7, size 9.1′ x 4.2′
NGC 3628: mag 10.3, size 14.8′ x 3.0′
Challenge: M66 asymetry, NGC 3628 dust lane, quasars and chain of optical objects (P)
Even at low magnification (to nicely frame the three galaxies) some details can be seen like the dustlane in NGC 3628, an arm curling from S to E on M66 and a brighter patch in M65 on the N side. The difference in brightness of the three galaxies can be noticed while all of them can be seen with direct vision. This is a magnificent sight at low power.
Arp 318 – NGC 833/835/838/839
NGC 833: mag 12.7, size 1.8′ x 0.7′
NGC 835: mag 12.1, size 1.3′ x 1.1′
NGC 838: mag 13.0, size 1.2′ x 0.9′
NGC 839: mag 13.1, size 1.6′ x 0.7′
Challenge: Tail from NGC 835 toward NGC 838 (N)
All four components are seen, but not the streamers. NGC 833 shows a bit of an ellipse and is not noticeably brighter in the center. NGC 835 is the most distinct member one of the group, it’s round with a bright core. NGC 838 is smaller en dimmer, but the stellar core is clearly visible. NGC 839 is a small and round glow without any central brightening, with AV it swells a bit more.
Arp 323 – NGC 7783 chain, Hickson 98 Galaxy chain
NGC 7783: mag 14.0; size 1.3′ x 0.7′
NGC 7783B: mag 15.0; size 0.4′ x 0.3′
NGC 7783C: mag 16.2; size 0.3′ x 0.2′
NGC 7783D: mag 16.9; size 0.3′ x 0.3′
Challenge: Distinguish all Hickson components (N)
NGC 7783 is the brightest member, seen as a clear knot at the N side of a curved, nebulous glow. At the S side NGC 7783B is seen as a somewhat dimmer and smaller knot. Betweetn these two galaxies a dim m14.9 is visible. Further S and fully separated from the above mentioned nebulosity a very dim star and NGC 7783C are seen loose from each other. The galaxy is very hard to discern with averted vision. A bright m10 star nearby disturbs a bit and (partially) prevents the final member NGC 7783D from being seen, but perhaps it’s just too dim.
Arp 326 – UGC 8610 and UGC 8613 galaxy chain
UGC 8610: mag 15.4, size 1.2′ x 0.4′
UGC 8613: mag 15.3, size 1.4′ x 0.6′
MCG+1-35-19: mag 15.3, size 0.6′ x 0.4′
LEDA 214126: mag 17.1, size 0.5′ x 0.2′
MAPS-NGP O_559_0677185: mag 17.4, size 0.4′ x 0.3′
MAPS-NGP O_559_0792305: mag 18.0, size 0.2′
MAPS-NGP O_559_0677872: mag 18.0, size 0.2′
Challenge: Seven named galaxies and the ring around MCG+1-35-19 (P)
Arp 326 consists of 7 galaxies, of which I could see 6. The two dimmest in this chain are mag 18, but I was able to locate them despite of that (with a lot of effort). the brightest member of the chain has its own designation: Arp 33, but the integral sign shape of UGC 8613 was invisible, it was only seen elongated. UGC 8610 was seen elongated too.
Arp 331 – NGC 379 – 388, Pisces Cloud Galaxy chain
NGC 373: mag 16.6, size 0.4′
NGC 375: mag 15.7 size 1.4′
NGC 379: mag 13.9, size 1.4′ x 0.8′
NGC 380: mag 13.6, size 1.4′ x 1.2′
NGC 382: mag 14.2, size 0.7′
NGC 383: mag 13.4, size 1.6′ x 1.4′
NGC 384: mag 14.0, size 1.1′ x 0.9′
NGC 385: mag 13.9, size 1.1′ x 1.0′
NGC 386: mag 15.4, size 0.9′ x 0.8′
NGC 387: mag 17.2, size 0.4′
NGC 388: mag 15.4, size 0.9′ x 0.8′
UGC 679: mag 16.6, size 1.0′ x 0.3′
Challenge: All twelve galaxies in Arp’s field (P)
In total, 11 galaxies were seen in a field of 23 arc minutes. Most prominent is NGC 383 in the center of the chain. It’s the brightest and largest member of the group. Very close to it is NGC 382, somewhat dimmer and smaller. NGC 380 and NGC 379 to the N are about the same in size and brightness. NGC 379 is the only member in the group that does not appear round, but is shaped like an ellips (2:1). On the S side, NGC 384 and NGC 385 mark the end of the chain. These galaxies are dimmer than the ones in the center and to the N. With some effort NGC 386 and NGC 375 are visible too as small and dim specks in the field. Finally, with a lot of effort and AV, NGC 373; NGC 387 and NGC 388 can be glimpsed as well as tiny specks of nebulosity. UGC 679 remains hidden.
Arp 333 – NGC 1024
mag 12.1; size 3.9′ x 1.4′
Challenge: Thin circular arms, star in SE superposed on whisp (N)
NGC 1024 is clearly seen as an oval shaped glow with some central brightening and slightly bent shape at the tips, which gives away the spiral structure. In a nice starfield there are two more galaxies: NGC 1029 is edge-on with a round core; NGC 1028 can only be seen with AV and with effort as a small, round dot. The superposed star was seen, but not the whisp.
Arp 336 – NGC 2685, The Helix Galaxy
mag 11.2, size 4.5′ x 2.4′
Challenge: Circumferential rings encircling cigar-shaped core (N)
Very bright, cigar-shaped, but small galaxy with a bright core that is slightly stretched. The rings are not visible.
Arp 337 – M82 (NGC 3034)
mag 8.4, size 11.4′ x 4.3′
Challenge: The filaments projecting from the center (N)
The “Cigar Galaxy“. Very bright and very large with many immediately visible details. Three dark lanes, of which one is very apparent, are seen perpendicular to the plane. Additionally, there is a dark “notch” just behind a mag 15 star. The core is split by the the thickest dark lane and has a very mottled appearance. Stunning!