As many of you know, I enjoy imaging objects that I have not seen before, to the extent that I have about 500 objects posted in the Astrobin Debut Objects (“First on Astrobin”) Collection.  For those of you who may be wondering how to identify such objects, 2 years ago Astrobin implemented the red button on each platesolved object image which reads “Find images in the same area”.  In my experience, if no other images show up when this button is pressed, one can be reasonably sure that the image is a debut object.  An exception is when an object is not able to be platesolved by Astrobin (due to image distortion or some other reason), in which case the database of course has no way of knowing that another image exists in the same area.

I recently have browsed through all of my debut objects.  Some of these objects have since been imaged many times, which makes me happy to see that these objects are now gaining in popularity.  But many more objects have still not been imaged a second time since I posted the original image.  For most of these, that is deserved – they are often boring and not fun to image.  But some of these “still debut” objects are very interesting to image and deserve more attention from the Astrobin community.  It is for that reason that I created this poster.

The poster contains 25 objects which, as of last week, have only been imaged 1 time on Astrobin.  If you are looking for a fun object to image which you haven’t seen before, give one of these a try.

Each image on the poster includes:
-  the object name
-  the declination (in degrees)
-  the apparent size (in arc-minutes), and
-  the distance from us (in light years for nebulae, or millions of light years for galaxies).  

For most of these images, the objects are relatively small and I recommend having a telescope focal length of at least 900 mm to image them with any detail.

Here are the top 25 ignored DSOs, starting with my favorite:

1. Zw II 96 - This pair of merging galaxies is located 0.5 billion light years away in the constellation of Delphinus at a declination of +17 degrees.  Both galaxies are severely disturbed and are in the late stage of a merger.  The object spans a Milky Way like diameter of 120,000 light years.  The tiny reddish region is a massive young starburst region, and in fact it is the most extreme starburst region found outside of a galaxy nucleus anywhere in the universe. 

2.  Arp 195 - This object, also known as UGC 4653, is a tiny galaxy triplet located 0.75 billion light years away in the constellation of Lynx at a declination of +35 degrees.   The shape of this object reminds me of a grasshopper, but there is already another Arp object with that same nickname (see poster object #13). But I think that this object is more worthy of that nickname.  The galaxies of this object span 3 arc-minutes in our apparent view, which corresponds to a span of over 200,000 light years. Arp classified this object into the interesting category of "Galaxies with material ejected from nuclei". This is an amazing object for 2 reasons. The first is that 3 galaxies can be aligned, all face-on, so closely together without much distortion. The second is the beautiful horizontal star stream which extends for almost 200,000 light years. I like that the blue color of this long star stream contrasts with the orange of the source galaxy.

3. vdB 35 - This reflection nebula is located 1200 light years away in the constellation of Orion at a declination of +13 degrees.  It spans 3.4 arc-minutes in our apparent view.  This corresponds to a width of 1.2 light years. The source star is HD 34033, a magnitude 8.7 star.  I think it is interesting that the star appears orange but the nebula is also a whitish-blue color.

4. NGC 3423 - This near face-on spiral galaxy is located 60 million light years away in the constellation of Sextans at a declination of +6 degrees.  It is a blue magnitude 12 galaxy which spans 4 arc-minutes in our apparent view.  This corresponds to a diameter of 70,000 light years.  This is a faint but beautiful spiral galaxy.  Numerous blue star clouds and purple emission regions are seen throughout the disk.  Dust lanes separate the disk into spiral arms that are hard to trace.  I like the 2 distant spiral galaxies just below NGC 3423, 1 billion light years away, which provide a nice size and color contrast to the main object.  

5. Kohoutek 1-2 - This planetary nebula is located 9000 light years away in the constellation of Pyxis at a declination of -29 degrees.  It is a magnitude 15.3 PN which spans 1.8 arc-minutes in our apparent view.  This corresponds to a diameter of 4 light years, twice the size of a typical PN.  This object is a member of the Kohoutek PN catalog.  The nebulae of many PN show the influence of bi-polar jets, but this is the only PN I know of which has a visible bi-polar jet.  The jet is emanating from the central progenitor white star, the binary star VW Pyx.  This binary has an orbital period of 0.7 days.  The bi-polar jet is ejecting in the 1 o’clock and 7 o’clock directions.   The existence of the jet-like feature of K1-2 was first reported in a 1989 publication.  Note that the bottom jet is not quite perfectly aligned with the progenitor star.  The nebula itself is also interesting.  It is dominant in OIII but has a strong HII region in the center.  I am puzzled why the nebula shape does not seem to be affected by the bi-polar jet structure.  They seem to be 2 independent features of this PN.

6. UGC 10273 - This small group of galaxies is located 360 million light years away in the constellation of Corona Borealis at a declination of +28 degrees.  The largest galaxy in the image is UGC 10273, the edge-on spiral galaxy at center. This object spans 1.5 arc-minutes in our apparent view, which corresponds to a large diameter of 160,000 light years. I like the changes in color along the galaxy, from blue to white to orange, then back to blue and finally white. Also, the galaxy seems interrupted in many places by dark bands, which I assume are dust lanes.  Just below and left is the orange small spiral galaxy LEDA 1831614, about the same distance away. I believe that there is interaction with the main object because of the faint star streams that are visible between them, but I can’t be 100% sure. It seems like this might be a rare case of an early stage merger of 2 galaxies which are both nearly edge-on to our view.  Further to the left is the lenticular or elliptical galaxy LEDA 1832284, also at a similar distance. It seems to be unaffected by gravitational interaction.  The big question to me is: What are the other 5 smaller faint objects nearby? They don’t look like distant galaxies to me. They seem to be faintly connected with the main object by star streams. My best guess is that they are fragments of the other 2 larger galaxies, torn away by the interaction.

7. DeHt1 - This planetary nebula is located 6200 light years away in the constellation of Lepus at a declination of -23 degrees.  It is the first object in the Dengel-Hartl planetary nebulae catalog.  The PN spans 2 arc-minutes in our apparent view, which corresponds to a diameter of 3.5 light years. This nebula is dominated by OIII signal. The progenitor is clearly visible as the small blue star at the center of the nebula, just left of the orange foreground star.  I love the unique crescent moon shape of this nebula.  It looks to me like the interstellar medium (ISM) has distorted this circular nebula to the right and down, making the PN look like it has a drop shadow.

8.  Arp 335 - This object, also known as NGC 3509, is a disturbed galaxy located 360 million light years away in the constellation of Leo at a declination of +5 degrees. The object spans 1.7 arc-minutes in our apparent view, which corresponds to a huge diameter of 180,000 light years.  Dr. Arp placed this object in his final catch-all category of Miscellaneous, perhaps indicating that he didn't know quite what to make of it. His notes simply say "large luminous system".  Over the years, some have felt that this object is 2 merging galaxies. Arp’s image could be interpreted as such. But we have the advantage today of imaging in color, and it is clear from my image that this is one galaxy, albeit very disturbed. The central yellow core looks fairly normal, but the rest of the galaxy is a fascinating funhouse of treasures. The galaxy has two strong arms, with one twice as long as the other. Numerous star clusters are visible, included one intensely bright blue area right below the core.  It is likely that a companion caused this disturbance in NGC 3509. Some smaller galaxies are visible nearby, but no conclusive work has been done to indicate whether any of these are responsible for the disturbance.  The distant tiny galaxies in the image are about 2 billion light years away.

9. NGC 7518 and UGC 12423 - This pair of beautiful spiral galaxies is located in the constellation of Pisces at a declination of +6 degrees. NGC 7518 is the barred spiral at the bottom, located 160 million light years away. This galaxy spans 1.4 arc-minutes in our apparent view, which corresponds to a diameter of 70,000 light years.   The arm structure defines a pseudo-ring around the yellow oval inner region.  Arm fragments extend out it what is best described as a wacky manner.  I like how the outer arms terminate in star plumes, wider for the top arm than for the bottom one.  UGC 12423 is the superthin edge-on spiral galaxy, further away at 220 million light years.  This is one of the largest diameter spiral galaxies in the sky, at twice the size of the Milky Way.  It spans 4 arc-minutes in our apparent view, which corresponds to a diameter of 250,000 light years.  I love the mid-line dust lane and how it tries to hide the yellow bulged core.  The galaxy is warped at each end, as many of these superthin galaxies are.  Many distant galaxies are seen in the background.

10.  Minkowski 2-9 - This object, often abbreviated M2-9, is a tiny bipolar planetary nebula located 5500 light years away in the constellation of Ophiuchus at a declination of -10 degrees. This nebula spans 1 arc-minute in our apparent view, which corresponds to an actual length of 2 light years.  The twin lobes of this object have formed from the outflow of a central binary system. Scientists have estimated that this process started about 1000 years ago. Unlike most planetary nebulae, the central star is reddish and not bluish. It is believed that this reddish star is the larger companion of the binary system.  Bipolar planetary nebulae are not that unusual. However, this one appears unique to me because of its thin aspect ratio, unlike a "fatter" bipolar nebula such as M76. My guess is that this thinner nature is due to the speed of the bi-polar jets, which is perhaps why this object is nicknamed the Twin Jet Nebula.

11. Berkeley 29 - This extragalactic open star cluster is located 40,000 light years away in the constellation of Gemini at a declination of +17 degrees.  This cluster spans 2 arc-minutes in our apparent view, which corresponds to a diameter of 20 light years.  This object has the distinction of being the most distant open cluster from the core of our galaxy.  It lies 70,000 light years from the galactic center.  It is believed to have originated outside of the Milky Way galaxy, in the Sagittarius Dwarf galaxy.  It is now within our Milky Way, as part of the former galaxy’s stellar stream.  It is amazing to me to realize that this open cluster is 100 times further away than M45 (Pleiades).  

12. UGC 12342 - This tiny obscure object is a pair of merging galaxies located 400 million light years away in the constellation of Pegasus at a declination of +17 degrees. The object spans just over 1 arc-minute in our apparent view, which corresponds to a true width of 150,000 light years.  This objects reminds me of a miniature version of Arp 244, the Antennae Galaxies. Here, the cores of the 2 merging galaxies are different colors - yellow on the left and blue on the right.

13. Arp 55 - This tiny Arp object, also known as UGC 4881, consists of two merging galaxies located over 500 million light years away in the constellation of Lynx. This object is much bigger than our Milky Way, with a span of over 150,000 light years.  This object was first given the nickname, "The Grasshopper", by the esteemed astrophysicist Dr. Boris Vorontsov-Velyaminov in a 1977 paper. Despite all of the time I have I spent with this object recently, I still don't think it looks like a grasshopper. At least, not like the ones we have where I live. It looks more like a shrimp to me.  The two galaxy cores are seen as the two brightest yellowish regions in the object. The cores of each merging galaxy are separated and distinct, but the disks of the galaxies have started to merge. Intense star formation is occurring, as seen by the bright blue line of clusters along the grasshopper's "tail". Three other faint galaxies are visible near the Grasshopper in this image and form a group with it.

14. NGC 2163 - This obscure object, also known as Cederblad 62, is a beautiful small reflection nebula located 3300 light years away in the constellation of Orion at a declination of +18 degrees. The magnitude 11 nebula has a length of about 3 arc-minutes, which corresponds to a width of 3 light years.  The star at the center is the 13th magnitude variable star LkHa208, a young star still enveloped by its prenatal cloud. Strong bipolar winds are interacting with the cloud and I expect that the reflection nebula, like other variable nebulae, is changing shape over short periods of time. I like the many shades of blue that can be seen in the nebula. The nebula dust cloud is part of the larger dark nebula LDN 1574.

15.  NGC 5750 -  This barred spiral ring galaxy is located 100 million light years away in the constellation of Virgo at a declination of 0 degrees.  It is a magnitude 16 galaxy which spans 3 arc-minutes in our apparent view.  This corresponds to a diameter of 80,000 light years.  This galaxy appears to us about 30 degrees from edge-on.  This galaxy has an interesting structure.  A bright small central core has a dark dust band cutting across the upper portion. The core is surrounded by a large circular bright region.  This region is connected by a faint bar to the inner ring.  The ring is not quite continuous.  Beyond the ring, the disk is diffuse.  Many galaxies have these inner rings.  The most interesting part of this galaxy is the extended tidal star streams.  The strongest one extends up at 10 o’clock and then straight up.  Two much fainter ones are seen at 9 o’clock and at 3 o’clock.  Usually, these streams are due to disturbance from another galaxy, but I do not see a companion here.  Perhaps it was a small galaxy whose remnants are seen in the 10 o’clock stream.

16. NGC 1421 - This object is a nearly edge-on spiral galaxy located 65 million light years away in the constellation of Eridanus at a declination of -14 degrees. It is a 11.4 magnitude galaxy that spans almost 4 arc-minutes in our apparent view, which corresponds to an actual diameter of 72,000 light years.   The core of this galaxy is offset significantly to the right, likely due to the disturbance of a companion object. Likewise, the galaxy arms are not symmetric. The arm on the left side is unusually long and is lit up by an initiation of many bright star clusters and Ha regions. The galaxy seems to have been disturbed by something, but I don't see any obvious candidates nearby. This is some conjecture on a possible companion located in the odd stubby arm at the lower right of the galaxy, but our nearly edge-on perspective makes such a determination difficult.

17. Minkowski 2-55 - This object, also known as PK 116 + 8.1, is a planetary nebula located 7800 light years away in the constellation of Cepheus at a declination of +70 degrees. The nebula spans 1 arc-minute in our apparent view, which corresponds to a width of 2 light years.   The PN looks primarily bi-polar and is mainly comprised of hydrogen. The intricate detail of the inner structure is very interesting and somewhat resembles that of Abell 31. I really don't understand the mechanism which is creating such an interesting geometric pattern in the central region.

18. UGC 711 - This superthin edge-on spiral galaxy is located 70 million light years away in the constellation of Cetus at a declination of +2 degrees.  It is a magnitude 13 galaxy which spans 4 arc-minutes in our apparent view, corresponding to a diameter of 80,000 light years.  I love these unusual superthin galaxies.  The formation mechanism for them is not well understood.  Like many superthin galaxies, UGC711 has no central bulge.  The disk is relatively featureless except for the presence of a few blue star clusters.  The 10th magnitude orange star is BD+00 190.

19. Hickson 4 - This is a galaxy group of 5 galaxies, called Hickson 4, located in the constellation of Cetus at a declination of -21 degrees.  Like many of the Hickson galaxies, this is not a true cluster - the 5 galaxies are all at different distances and are only aligned through superposition from our apparent view. Most of the galaxies are about 0.3 to 0.4 billion light years away, although the dimmest one is almost 1 billion light years away.  The brightest galaxy in the group is also the largest.  This galaxy is a pretty grand spiral and is a Milky Way size galaxy at about 110,000 light years in diameter.  There is a 6th distant galaxy in the group, in the lower left corner of the image, that Hickson missed.  Perhaps it was mistaken for a star, or deemed as too small to include in the group (although other Hickson objects include galaxies this small).

20. Shakhbazian 1  - The object at the center of this image looks like a sparse open star cluster.  But it is not.  This object is a distant galaxy cluster located 1.5 billion light years away in the constellation of Ursa Major at a declination of +40 degrees.  It is also known as MLCG 0081.  It is very dense, with 17 galaxies contained within a 1 arc-minute circle.  That circle corresponds to a 500,000 light year diameter. Studies have shown that this is a true cluster, with all 17 galaxies at the same distance away.  The largest and brightest galaxy, LEDA 32808, is the elliptical galaxy at center.  It is about 70,000 light years in diameter.  The cluster was discovered in 1957 by the Armenian astronomer Dr. Romela Shakhbazian.  Dr. Shakhbazian catalogued 377 compact groups of galaxies.   The blue object just to the left is a magnitude 18 Seyfert galaxy, Mrk 1269, which is at the same 1.5 billion light year distance. 

21.  NGC 812 -  This spiral galaxy, if it can even be called that, is located 175 million light years away in the constellation of Andromeda at a declination of +45 degrees. This galaxy spans 2.3 arc-minutes in our apparent view, which corresponds to a diameter of 120,000 light years.  This is such an interesting object to me. It looks like a lizard searching for dinner. I love so many things about it - the odd asymmetric structure, the messy inner core region, the bright orange and blue colors, the bright star clusters, and most interestingly the curving nature of the entire galaxy. I have never seen another galaxy shaped like this.  This galaxy is obviously disturbed but what caused it? I don't see a companion anywhere in sight. 

22. UGC 9560 & UGC 9562 - This obscure target is a pair of tiny dwarf galaxies is located in the constellation of Bootes at a declination of +36 degrees. Both galaxies are about 70 million light years away.  UGC 9562 is on the left, its companion UGC 9560 on the right. The galaxies are also known as II Zw 71 and II Zw 70 respectively. These galaxies are small – each spans 1 arc-minute in our apparent view and has an actual diameter of about 20,000 light years. The two galaxies are separated by about 100,000 light years.  Both galaxies have interesting structures. UGC 9562 is a polar ring galaxy, as described in the 2000 paper, “Stars & Gas in the Galaxy Pair II Zw 70/71”, by Cox, Sparke, Watson and van Moorsel. This polar ring galaxy is probably the strangest one I have ever seen. The white disk is a typical lenticular disk, extending from lower left to upper right. Perpendicular to this is a blue arcing stream of stars with several HII knots.  UGC 9560 has a bluish core and a warped whitish disk. Detailed studies reveal a faint stream of gas connecting these 2 galaxies. The paper describes this galaxy pair as one of the best known candidates for a polar ring in the process of formation by accretion of gas from a nearby companion.

23. NGC 150 - This spiral galaxy is located 70 million light years away in the constellation of Sculptor at a declination of -28 degrees.  It is a magnitude 11 galaxy which spans 2 arc-minutes in our apparent view.  This corresponds to a diameter of about 45,000 light years.  We are seeing this galaxy about 30 degrees from edge-on.  Both the color and structure of this small galaxy fascinate me.  The core is yellow, the arms are mostly blue, and some pink HII regions can be seen.   The structure is similar to a grand spiral but has additional arm fragments which are difficult to trace.  This could be the result of interaction with another galaxy, especially since faint star streams extends out to the lower left and upper right, but I don’t see an obvious candidate for a companion.

24. NGC 2793 - This object is a small ring galaxy located 80 million light years away in the constellation of Lynx at a declination of +34 degrees. This galaxy spans 1 arc-minute in our apparent view, which corresponds to an actual diameter of 30,000 light years.  This galaxy is strange – a bright rectangular offset core, surrounded by a diffuse disk which contains half of a star cluster ring. The galaxy just above and right is PGC 82356. I love the look of the two small galaxies “connected” by a few small orange stars.  Many galaxy rings are believed to be the result of galaxy collisions. Some have speculated that the smaller galaxy in this case may have “punched a hole” in the larger galaxy while passing through it and creating the ring. While this is a very intriguing idea, the reality is that the smaller galaxy is much further away and not interacting with the larger galaxy.  No companion to NGC2793 has yet to be found, so as of now the source of the ring structure is a mystery.

25. NGC 7723 - This barred spiral galaxy is located 100 million light years away in the constellation of Aquarius at a declination of -13 degrees.  It spans 3 arc-minutes in our apparent view, which corresponds to a diameter of 90,000 light years.  Our view of the disk is about half-way between edge-on and face-on.  Yellow dominates both the core and disk.  The arms emanate from the end of the bar and quickly fragment after about 90 degrees of rotation.  The outer portion of the disk is diffuse.


That brings us to the end of this collection of most neglected DSOs.  I hope this bit of exposure can help these ignored galaxies find a bit more love and attention from our Astrobin community.  If you do image one of these, please let me know and link an image of it in the comments below.