Galaxy of the Month Archive 2024
In this series of articles we draw your attention to galaxies particularly worthly of an observer's time.
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NGC 1275 and ACO 426 in Perseus
November 2024 - Galaxy of the Month
I am surprised I have not covered this Abell cluster in Perseus in the GOM series before as it is the standout galaxy cluster in the autumn sky. The cluster lies at a distance of about 240 million light-years from us and is the major component of the Pisces-Perseus super cluster.
This cluster contains thousands of galaxies immersed in a halo of hot X-Ray emitting gas and is believed to be one of the most massive objects in the local universe. The cluster is of the linear type in the Rood-Shastry galaxy cluster classification. This can be seen well in the wide field image from the Euclid satellite. It has an Abell richness class of 2, so it is not regarded as a terribly rich cluster but its closeness to us means there are many galaxies that can be seen ( a richness class of 2 suggests there are between 80 and 129 galaxies in the range m3 to m3+2).
The BCG is the active galaxy NGC 1275 which in deep images shows streams of H-Alpha emission. NGC 1275 is also the Perseus A radio source, the brightest radio source in Perseus. NGC 1275 is at the right-hand side of the cluster along with the other bright galaxies NGC 1272 and NGC 1278. Most of the rest of the galaxies lie along the line to NGC 1250. There are however a couple of bright galaxies that are often missed as they are off the centre line, NGC 1265 and NGC 1282. The total cluster diameter is 17.9’.
The whole Pisces-Perseus cluster stretches perhaps 40 degrees across the sky. An observing guide to the supercluster can be found at Adventures in Deep Space.
Most of the galaxies in Abell 426 appear to be early types (i.e. elliptical and lenticular galaxies) although there are a fair number of spiral galaxies as well. The cluster was also recently shown to contain a large number of low surface brightness dwarf ellipticals. The presence of the spiral galaxies suggests that the cluster is still evolving by accreting local galaxy groups. X-Ray observations suggest that the gas in the cluster is sloshing around generating very low frequency sound waves.
For those interested in future telescopes the following video shows the FOV of the upcoming Nancy Roman telescope compared to Hubble. There is also a recently released image of part of the cluster from the Gemini North telescope.
Although the brighter members of the cluster can be seen with smaller telescopes the cluster really comes into its own when viewed with larger instruments when more than 10 galaxies can be seen in the same field of view when looking at the centre of the cluster. I find that using a medium to high power eyepiece will help bring out the majority of the galaxies in the field and then moving along the main band of the cluster will bring out many more. When looking at the cluster do not forget to view the larger off band galaxies as well.
The cluster is well covered in the Webb Society Deep-Sky Observer's Handbook (WSDSOH) Vol. 5 and makes the Astronomical League clusters of galaxies list as well. There is also a nice report on Cloudy Nights. The cluster is also in Alvin Huey’s Abell clusters guide at FaintFuzzies.com and there is a chart for it in Luginbuhl and Skiff (L&S).
Owen Brazell - Galaxy Section Director
If you'd like to try out the Clear Skies Observing Guides (CSOG), you can download observing guide for the current Galaxy of the Month without the need to register. CSOG are not associated with the Webb Deep-Sky Society but the work of Victor van Wulfen.
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NGC 1161 and NGC 1160 in Perseus
October 2024 - Galaxy of the Month
For this month I am choosing the nice pair of galaxies in Perseus, NGC 1161 and NGC 1160. Both of these galaxies were discovered by William Herschel in 1784, although NGC 1160 was also independently rediscovered by R.J. Mitchell using Lord Rosse’s 72” at Birr.
NGC 1161 is classified as a Seyfert galaxy with a classification of 1.9 (or possibly type 2), it is also classified as an AGN of the LINER type. NGC 1161 is a lenticular galaxy of type S0 whilst NGC 1160 is classified as a flocculent spiral of type SBc, or possibly Scd, seen close to edge on. The distance given for NGC 1160 is about 116 million light-years so it lies quite a bit beyond NGC 1160 which lies at about 90 million light-years.
NGC 1160 does seem to have a lot of star formation going on in it given the blue nature of its spiral arms. This is slightly unusual as lying in the void there is nothing for it to interact with to cause all this star formation. The galaxies are not a physical pair but both lie near the centre of the local void between our local supercluster and the Perseus cluster, Abell 426.
As a quick aside it appears that most galaxies lie on filaments on the edge of voids where very few galaxies appear to be. This means by studying galaxies in voids we can see how they evolve when not disturbed by interactions.
There is a nice amateur image of the pair by José Manuel López Arlandis on Astrobin. See also the Mantrap Skies Catalog entry for these galaxies which shows an interesting HST image of the internal part of NGC 1161 which appears to show an inner ring of dust clouds.
There does not appear to be much research done on either of these two which I find quite surprising as there is always interest in galaxies that are evolving without interacting with others. Perhaps as expected the area also has issues with galactic cirrus for imagers.
NGC 1161 does make it into the Astronomical League's Herschel II list but, perhaps as expected, not into any other observing lists.
The galaxies are a very tight pair and will fit into the field of view of a high-power eyepiece. There is a bright double star on the edge of NGC 1161 which may hinder viewing, HJ 2167. It is actually a triple star system with the third star lying in NGC 1161. The The Night Sky Observer's Guide (NSOG) Volume 1, now sadly out of print, suggests that the pair are targets for 40-45cm telescopes but I would have thought that since William Herschel found both of them, they should be visible in smaller apertures, perhaps down to 20-25cm.
Owen Brazell - Galaxy Section Director
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NGC 672 in Triangulum
September 2024 - Galaxy of the Month
My challenge this month is the pair of galaxies in Triangulum, NGC 672 and IC 1727. NGC 672 was first discovered by William Herschel in 1786 and is an interesting galaxy which is part of an interacting pair with IC 1727. IC 1727 is much fainter than NGC 672 and was discovered photographically by Isaac Roberts in 1896. I am surprised that I have not covered them before.
The two galaxies are separated in space by perhaps only 88,000 light-years, which is about the diameter of one of the galaxies. The whole system is enveloped in a cloud of hydrogen gas and loose stars. There appears to be a tidal bridge between the two galaxies which shows up in radio observations made in the neutral hydrogen line (HI) at 21cm. The group lies less than 20 million light-years from the Milky Way.
Perhaps surprisingly given the obvious nature of the interaction is that NGC 672 did not make it into Halton Arp’s catalogue of peculiar galaxies, although it did make it into the Vorontsov-Velyaminov (VV) catalogue of interacting galaxies as number 338.
The colour of the galaxies is fairly blue due to all the star formation going on in them. Images from the UV satellite GALEX shows lots of evidence for new star formation. The total magnitude difference between the two galaxies is not that much, being 11.5 for NGC 672 and 12.1 for IC 1727, but the surface brightness is very different between the two which is why IC 1727 is so much more difficult to see. They are both barred spiral galaxies but IC 1727 is highly disturbed.
The pair appear to be part of a small group of galaxies which includes 4 dwarf galaxies as well. There is some suggestion that NGC 672 and its group of galaxies, along with the NGC 784 group, lie on a local dark matter filament which has been responsible for the growth of the galaxies.
Visually NGC 672 should be an easy target in a 20cm telescope but IC 1727 is likely to require a 30cm aperture or greater and a good night to find because of its low surface brightness. Using larger apertures on NGC 672 may show some of the large star clusters and other detail in its bar. As a bonus there is the nice edge on galaxy NGC 684 about half a degree to the NNE of NGC 672. This may be a challenge for larger telescopes.
NGC 672 makes it into the Astronomical Leagues Herschel II list as well as their Two in a View list. Along with the nearby NGC 684 it is also in Alvin Huey’s Galaxy Trios list.
Both of these galaxies appear in the Webb Society Deep-Sky Observer's Handbook (WSDSOH) Vol. 4 where it is suggested that they are both visible in a 25cm telescope, although IC 1727 was difficult. The The Night Sky Observer's Guide (NSOG) Volume 1 however suggests that a 30cm telescope is needed to see IC 1727 whilst NGC 672 can be seen with 15cm but the larger the telescope you use the more detail can be seen. Luginbuhl and Skiff (L&S) also suggest that IC 1727 can be seen in 25cm. You need to note however that all their observations were made at high altitude and will not reflect what can be seen with increased light pollution and crud with the extra depth of atmosphere over the UK.
Owen Brazell - Galaxy Section Director
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NGC 6308 in Hercules
August 2024 - Galaxy of the Month
With the month of August we now get true dark skies again from the UK, and I am going to continue in this GOM with the objects discovered by Albert Marth theme from last month, and for this we have a nice line of galaxies discovered by him in Hercules. These are the galaxies NGC 6308, NGC 6314 and NGC 6315. They hold pride of place in Marth’s listing as they were the first galaxies that he discovered using William Lassell’s 48” speculum metal mirror telescope from Malta. All of these objects appear to be spiral galaxies with NGC 6308 and NGC 6315 being almost face on and NGC 6314 edge on.
NGC 6308 has a bright core and is listed as a Seyfert Type II, a form of AGN. Type II Seyfert galaxies have very narrow emission lines in their spectrum compared to those of type I. It may be that the classification into Type I or type II depends on the angle at which we view the nuclear region. NGC 6308 does not appear to be related to the other two, which may form a physical pair, but is purely a line-of-sight coincidence. NGC 6308 lies about 130 Mpc from us.
It is suggested that NGC 6314 and NGC 6315 may form a pair at about 71 Mpc from us, however a more recent observation suggests they too are a line-of-sight pair and may be separated by as much as 6 Mpc. It appears that NGC 6314 also contains an AGN of the LINER type. Although NGC 6315 does not appear to contain an AGN it is classified as an emission line galaxy and the GALEX UV image is very strong so it is likely that a lot of star formation is going on here. This would be consistent with its blue colours. Not much research appears to have been done on these galaxies.
Perhaps as expected with the galaxies that Marth found there are no observations of this group of galaxies in any of the standard references. The group is tight enough that all the galaxies will fit in the field of view of a medium power (260x) hyperwide eyepiece. Steve Gottlieb describes them as fairly faint in a 17.5” telescope so I suspect that 50cm may be required to find them from the UK, although 45cm may do. The galaxies pass very high up as seen from UK latitudes so it should be easy to track the field down.
Owen Brazell - Galaxy Section Director
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NGC 6368 in Ophiuchus
July 2024 - Galaxy of the Month
I apologise that the GOM is going to be rather short this month as there is a shortage of galaxies in the twilit summer skies. Our challenge this month may also be tricky on account of its faintness.
The galaxy NGC 6368 in Ophiuchus was missed by William Herschel and was discovered in 1863 by Albert Marth using William Lassell’s 48” speculum metal mirror telescope in Malta. Marth was a prolific observer of faint nebulae and discovered 583 new objects that made it into the NGC, along with one that made it into the IC.
As an aside many years ago Alan Dowdell wrote a paper in the Webb Quarterly Journal about Marth’s observations, and at that time it was very difficult to get access to the original paper whereas now it is freely downloadable.
NGC 6368 itself appears to be a nearly edge on spiral galaxy of type Sb lying at a distance of perhaps 32 Mpc. NGC 6368 appears to be an isolated field galaxy and as far as I can see not much research has been done on it. SIMBAD suggests that it may be a candidate for having an AGN. There are also suggestions that it may be part of an outlying galaxy filament of the Virgo cluster. NGC 6368 is a relatively small galaxy with a calculated diameter of only 49,000 light-years.
NGC 6368 lies very near the border with Hercules so it does rise pretty high as seen from the UK, this may help when observing it. I note that it can be seen from the UK with 40cm but is not described as terribly impressive, although it is not clear under what circumstances that observation was made. My suspicion is that probably only the central part of the galaxy was seen. Perhaps unsurprisingly NGC 6368 does not feature in any of the standard observation guides so any observations of it are of interest.
Owen Brazell - Galaxy Section Director
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NGC 5614 in Boötes
June 2024 - Galaxy of the Month
Now into June only the brightest galaxies can be seen from the latitude of the UK and I have chosen NGC 5614 in Boötes, also known as part of the Arp 178 triplet, for this GOM.
First discovered by William Herschel in 1785, NGC 5614 is a barred spiral galaxy lying at about 60 Mpc from the earth. The other members of the Arp 178 triplet are NGC 5613 and NGC 5615. NGC 5613 is however an unrelated galaxy lying almost twice as far away as the other two.
NGC 5614 sports a large tidal plume that has come from a gravitational interaction with another galaxy in the past. It is perhaps logical to assume this has come from NGC 5615 which is buried in the arms of NGC 5614. It is interesting to note that it took Bindon Stoney using the 72” at Birr to discover NGC 5615 in 1851. It is likely that NGC 5615 is the remains of a galaxy being torn apart by NGC 5614. Currently however it seems to lie about 3 million light-years from NGC 5614 (further than the Milky Way M31 distance) if so it must be in a long looping orbit.
Given their distances, NGC 5614 maybe about 130,000 light-years across and NGC 5615 only 10,000 light-years across.
One arm of NGC 5614 shows up very prominently in the UV image from GALEX which suggests a lot of star formation going on, and indeed the PanSTARRS image shows a number of clumps in that arm which could be new large young star clusters.
Observationally NGC 5614 should be relatively easy to find. The others given their discovery history will be much more challenging. NGC 5615 lies in the halo of NGC 5614 and will appear almost stellar and is probably going to be a challenge for large telescopes. NGC 5613 should be easier and in the range of 37cm or so. The group is very compact so a high magnification eyepiece will be required to split the group, perhaps of the order of 350x if the seeing conditions and telescope can take it.
The The Night Sky Observer's Guide (NSOG) Vol. 2 suggests that using a 30-35cm scope NGC 5614 is a faint circular patch, but using a 40-45cm scope will show all the galaxies in the group, although here again NGC 5615 is a tough call in the halo of NGC 5614. Steve Gottlieb suggest that NGC 5615 is an averted vision object with 45cm and a faint spot with 55cm, so this is going to be a challenge to find. He also suggests that NGC 5613 is similar in difficulty. There is a fine image of the group by Adam Block and the Mount Lemmon SkyCenter on Wikipedia.
Owen Brazell - Galaxy Section Director
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NGC 4365 in Virgo
May 2024 - Galaxy of the Month
Early May ends the serious galaxy observing season for the Spring in the UK, not that we really had one with the terrible weather in Spring 2024 here, as astronomical dark disappears until mid-August.
I am indebted to Mark Stuart for bringing my attention to this interesting galaxy group in Virgo. NGC 4365 is an interesting and bright galaxy that should be visible in small telescopes, however the interest here lies in the small group of galaxies below it including NGC 4341, NGC 4342 and NGC 4343 along with the fainter galaxies IC 3259 and IC 3267.
All of the NGC galaxies here were found by William Herschel in 1784. The two IC galaxies were found by Bigourdan using the 12.4” refractor from Paris in 1895. Unfortunately, observations in the classical period also rather scrambled the NGC and IC numbering of the galaxies in this group as William and John did not give positions for the individual galaxies they discovered. There does seem to have been a lot of confusion over the galaxy identification in the field but I think what we have now is correct. See Harold Corwin’s notes on these in his Historically-aware NGC/IC Positions and Notes.
The E3 galaxy NGC 4365 is the central galaxy of the W cloud in the Virgo cluster lying about 6 Mpc behind the main supercluster with a distance of about 22.8 Mpc. NGC 4365 appears to be stripping globular clusters and stars from NGC 4362 and the two galaxies are tidally interacting. For more on NGC 4365 see ESO's article Elliptical Galaxy NGC 4365 With Numerous Young Star Clusters.
Interestingly the galaxies in this area appear to be assigned to different galaxy groups in LGG 292 and LGG 295 and the area does seem rather confused as to what galaxies go where. The group is also included in the WBL catalogue of poor clusters as number 403. I note that the group is also suggested to be a Hickson like compact group. There is an interesting wide field view of this region on Jim Thommes' website.
NGC 4341 and NGC 4342 are suspected to be lenticular galaxies, whilst NGC 4343 is an edge on spiral that hosts an AGN of the LINER variety at its centre. NGC 4342 has been suggested to have an unusually massive central black hole for its size and is X-Ray luminous. Both the IC galaxies appear to be spirals, and according to their brightness in the UV from the GALEX satellite are currently undergoing a lot of star formation. The same would apply to NGC 4343. It seems that Hubble imaged part of the galaxy, although I only see this in the Wikipedia entry. Chandra also observed the group in X-Rays and showed that both NGC 4341 and 4342 are surrounded by a large amount of very hot gas.
The observations of this group in the The Night Sky Observer's Guide (NSOG) Vol. 2 are confused as they refer to NGC 4341 and NGC 4342 by IC numbers rather than the NGC numbers assigned to them today. The suggestion is that a 30-35cm scope is needed to see the brighter ones but a 40-45cm will do better. There are no observations of IC 3259 and IC 3267. It is probably worth remembering that the observations the NSOG are based on are over 40 years old now. Steve Gottlieb’s notes suggest that at least 32cm is needed and he normally observers from a high altitude site, to see these galaxies. He suggests that at least a 17.5” is needed to see the IC pair which suggests from the UK that maybe 50cm is needed from a good site. This is the size of scope that Mark Stuart was using for his own observations.
Owen Brazell - Galaxy Section Director
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NGC 5903 in Libra
April 2024 - Galaxy of the Month
With the month of April comes the real end of the galaxy observing season at higher latitudes as the increase in daylight combined with the move to Daylight Savings Time means we have less hours of useable darkness.
My choice of galaxy this month is NGC 5903 in Libra. Discovered in 1784 by William Herschel, NGC 5903 is an elliptical galaxy classified as an E2. It is going to be a challenge to observe from the latitude of the UK as it never rises that high above the horizon.
It forms a non-interacting pair with the elliptical galaxy (E0) NGC 5898 and also a triplet with the lenticular MCG-4-36-7, which is a very much fainter galaxy. It is also part of a small 5 galaxy group catalogued as LGG 398. The group is thought to lie at a distance of perhaps 36 Mpc. More recent observation suggest that there may be as many as 30 members of the group, although most of these are small and faint.
The faint galaxy MCG-4-36-7 appears to be a strong double lobed radio and X-Ray source.
NGC 5903 is unusual in that it appears to have a long filament of neutral hydrogen lying across the galaxy. The filament is approximately 100kpc long. Its origin is unknown but it is probable that it was caused by AGN activity in NGC 5903 in the past.
Both NGC 5903 and NGC 5898 are about half the size of the Milky Way given their distances. Perhaps surprisingly there does not seem to have been much other research done on this group.
The group is in the Astronomical Leagues Herschel 3 list of mostly faint galaxies. It is also in Alvin Huey’s guide to galaxy triplets and in Miles Paul’s atlas of compact galaxy triplets (downloadable from the Webb Society’s web site).
Both Luginbuhl and Skiff (L&S) and the The Night Sky Observer's Guide Vol.2 suggest a 20-25 cm scope are needed to see this pair, which may well translate to 25-30cm from the UK given the fact that they never rise that high. The best chances to observe them, as ever, will be when they are on the meridian and with a good light pollution free southern horizon. As both of the main galaxies are ellipticals there will not be much detail to be seen and smaller telescopes may only show the bright cores. Larger ones may show the haze surrounding the core. The triplet is close enough together that they will all fit in the field of view in a high power eyepiece and this may be the best way of finding them as it will increase the contrast between the galaxies and the background sky.
Owen Brazell - Galaxy Section Director
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NGC 3169 in Sextans
March 2024 - Galaxy of the Month
My choice this month is the galaxy trio in Sextans NGC 3169, NGC 3166 and NGC 3165. I can’t believe I have not covered this trio before so my apologies if I have.
NGC 3166 and NGC 3169 were discovered by William Herschel in December 1783 but it took until 1856 when Mitchell observing with the 72” at Birr found the much fainter NGC 3165. It appears that NGC 3166 and NGC 3169 are interacting strongly from the distortions seen in NGC 3169. The distance to all three galaxies is about 65 million light-years so it is likely that they form a physical group. It is probable that all three galaxies will eventually merge and for a single elliptical galaxy.
There is an excellent deep image of the group on Mark Hanson's website showing the tidal tails and interactions between NGC 3166 and NGC 3169. NGC 3165 is the bluer galaxy off to the right. There is also a fine image of the group taken with a 4m telescope at Kitt Peak. Images in the UV from GALEX show that NGC 3169 and NGC 3165 are showing signs of elevated star formation whilst NGC 3166 does not seem to show so much. Both NGC 3166 and NGC 3169 have active galactic nuclei of the LINER type. For a detailed view of NGC 3169 Hubble also shot the field.
The galaxies are also part of the galaxy group LGG 192 which contains 5 galaxies, including the three in this field and the nearby NGC 3156. They are also part of the larger Leo I group which is part of the Virgo cluster, see the Atlas of the Universe for more information on the Leo I group.
It is suggested that the activity in the central region of NGC 3169 is powered by a supermassive black hole. NGC 3166 and NGC 3169 are separated by only 160,000 light-years, so less distance than that separating us and the Magellanic clouds. NGC 3169 was also host to two supernovae in the last 25 years. Whilst NGC 3169 is classified as a spiral galaxy, albeit very distorted, NGC 3166 appears to be a lenticular with a smooth bar (SAB0(a)rs), although deep images do show some dust lanes. It also hosted a supernova in 2012. NGC 3165 is also classified as a spiral.
Both NGC 3166 and NGC 3169 appear in the Webb Society Deep-Sky Observer's Handbook (WSDSOH) Vol. 4 with observations with 16cm up to 40cm. The Night Sky Observer's Guide Vol. 2 suggests that 20-25cm will show NGC 3166 and NGC 3169 as elongated patches but not with much detail. They suggest that 40-45cm maybe needed to find NGC 3165. Luginbuhl and Skiff (L&S) suggest that NGC 3165 maybe glimpsed with averted vision with 25cm, however I suspect this was from a high altitude site. Hartung also briefly covers them suggesting that from his location they are right in 15cm (although this was rural Australia) and show in a nice star field.
For those that like collecting lists, NGC 3166 and NGC 3169 are in the Astronomical League's Herschel 400 list as well as Stephen O’Meara’s The Secret Deep book (numbers 40 and 41), along with many others.
Owen Brazell - Galaxy Section Director
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ACO 779 in Lynx
February 2024 - Galaxy of the Month
This month’s challenge is the galaxy cluster ACO 779 in Lynx. Containing at least 7 galaxies found in the NGC this should be a decent target for medium to large scopes.
The BCG (Brightest Cluster galaxy) is the giant elliptical galaxy NGC 2832, classified as a cD galaxy, also classified as E2, NGC 2832 itself was discovered by William Herschel in 1785. Most of the rest of the group appear to have been discovered by Stoney using Lord Rosse’s 72” at Birr. The Lord Rosse team found 12 galaxies in this area.
The group seems to contain mostly spirals and lenticulars with an interacting group from the extended VV catalogue in the centre. The same pair is also known as Arp 315, although this may apply to the three galaxies NGC 2830, NGC 2831 and NGC 2832. The galaxies in Arp 315 do not appear to be interacting.
ACO 779 is quite a small cluster with maybe 83 members and lies maybe 300 million light-years away. The Abell richness class however is 0 which suggests that there may be only 30 galaxies actually in the group. It covers roughly 50 arcminutes on the sky, although deep observations suggest it is more like 90 arcminutes, and lies roughly 40 arcminutes south of Alpha Lyn so it should not be that hard to find.
The group also contains a number of blue compact dwarf galaxies which appear to be forming stars at this time. There are some suggestions given its distance and location that ACO 779 may be part of the extended substructure of the Coma galaxy filament. There does appear to be some confusion regarding the NGC numbers in the group. NGC 2832 is certain but the others have been shuffled around a bit over time.
There is a decent amateur image of the group on Bernhard Hubl's website. I think observing this cluster will be best done with a chart as some of the fainter galaxies may look stellar. There is an interesting drawing available on X (Twitter) was made with a relatively small telescope, although this observers drawings appear to have some question marks about them.
A chart for the cluster can be found in Alvin Huey’s guide to observing Abell Clusters at which can be downloaded from his website. Steve Gottlieb suggests that NGC 2832 is visible in 13” but the others require a larger telescope, which given he usually observes in the high mountains suggests the group may require 45-50 cm to pick up more than the main galaxy. The Night Sky Observer's Guide (NSOG) Vol.1 suggests that a 20cm may show NGC 2832 and 30-35cm will show one of the others but 40-45cm are needed to show more galaxies in the group. The group is included in the Astronomical League’s groups and galaxy clusters program as well as in the SAC list of galaxy clusters.
Owen Brazell - Galaxy Section Director
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NGC 3414 in Leo Minor
January 2024 - Galaxy of the Month
Our galaxy this month is the lenticular galaxy NGC 3414 in Leo Minor. First discovered by William Herschel in 1785 it is the central galaxy of the rich galaxy group known as the NGC 3504 group, which in turn is also part of the Leo II group, a series of clusters on the edge of the Virgo cluster. The group is also catalogued as LGG 227, a cluster of 9 galaxies. For more information on the Leo II group see An Atlas of the Universe.
NGC 3414 is also known as Arp 162 and has a weak AGN of the LINER type. The Arp listing also includes NGC 3418, another nearby lenticular galaxy, although recent classifications suggest that this is a spiral galaxy. Interestingly the gas flows in NGC 3414 appear to follow a spiral pattern, however the gas in the inner part rotates in a different direction for the outer part. Deeper images also show signs of shells so all of this could be due to a recent merger. NGC 3414 also has a very strong bar in images.
NGC 3414 lies at a distance of perhaps 23 Mpc and NGC 3418 lies perhaps 800,000 lyrs from NGC 3414. If NGC 3414 is at this distance, then it is perhaps 40,000 light-years across, perhaps half the size of our Milky Way Galaxy. NGC 3414 is classified as S0pec.
It is probable that UGC 5958, a nearby edge on galaxy, is also associated with NGC 3414. Observations in the UV part of the spectrum with the GALEX satellite shows the bright core of NGC 3414 but also shows active regions in both NGC 3418 and UGC 5958 suggesting the galaxies are interacting. There also appear to be a number of dwarf spheroidal galaxies associated with NGC 3414, although these are far beyond amateur visual observations.
NGC 3414 is bright enough to make it into the Herschel 400 list of the Astronomical League. Observations from the UK suggest that NGC 3414 can be seen in 20cm but NGC 3418 is tough in a 40cm., however other observations suggest that NGC 3418 is visible in 30cm under very dark skies, although the quality of the site here was not defined. The The Night Sky Observer's Guide (NSOG) Vol. 2 suggests that 20-25cm telescopes will show NGC 3418 as a bright core but that 30-35cm is needed to show NGC 3818. Luginbuhl and Skiff (L&S) suggest that 25cm is needed to show NGC 3414 clearly and again it shows a bright core.
Owen Brazell - Galaxy Section Director