Caoimhín's Content

Today we are going to be looking at some galaxies, we’re going to be looking at some galaxies that are well placed to be seen at this particular time of the year.

For this piece, we are looking at sky from the middle of May to late May, roughly from the 15th to 20th this should hold pretty well. The Full Moon is on the 12th this month, so we want to be later than that, we want the Full Moon to be out of the sky early in the evening. Looking south once the sky is dar, Arcturus will be there, nice and bright, pretty much due south and reasonably high in the sky. The blue star Spica will be just underneath it, bringing you to the body of Virgo. Over towards the southwest, and higher than Spice, we have the tail of Leo. The sickle of Leo is perhaps easier to spot, but just east from the pointy tail of Leo is the head of Virgo and this region of the sky is filled with galaxies. There’s loads of galaxies that aren’t too far away from us in this direction, so if you have a telescope, this is a great area of the sky to point it and take a closer look.

Just zooming in a little bit and already we start to see fuzzy shapes, even from the city. We don’t need to head to the countryside yet, we’re going to take a closer look from a city like Cork. I will remind the reader that Cork is still about a Bortle 5 in terms of light pollution, which is quite good for a city. Many cities are closer to 7 or 8, with the brightest light polluted skies being 9. From a level 5 sky, which is still certainly light polluted, we can see some of those beautiful groups of galaxies. There are many galaxies that, to us here on Earth at least appear close together, and some of these galaxies are genuinely close together. They are of course spread out three-dimensionally, some of them are further behind the others, but a lot of them are in the same cluster. This is the Virgo Cluster of galaxies. This cluster, along with the Local Group, forms in the Virgo Supercluster. This cluster of galaxies in Virgo forms a group with our little cluster of galaxies, the Andromeda Galaxy, the Milky Way and the Triangulum Galaxy. Andromeda and Triangulum are our closest neighbors, that’s our Local Group, but then we are part of a larger group, a supercluster, along with these galaxies in Virgo. In Stellarium, there are object labels that we can bring up to highlight deep sky object. This makes it a lot easier to see, and select, these galaxies.

Selecting the Virgo Galaxy or M87 as an example, this lets us use a simulated telescope to take a closer look. Immediately, it’s clearly a nice bright galaxy, though it looks like a big ball of stars or a faint fuzzy star itself. This is an elliptical galaxy rather than a spiral galaxy. A lot of these Virgo galaxies are elliptical galaxies. In Stellarium, Various morphological classifications can be shown for a galaxy. In this case there is an E for elliptical. These galaxies can be elliptical or lenticular, with lenticular galaxies being more disc like and given the letter S, usually S0. In one classification system, E0 is more round and E7 is flatter, but still rounded with no arms. Due to the generally rounded shape, these galaxies are often a little indistinct. M87 is an E0-E1, or E+0-1 pec, just a little ellipsoidal. This is visible even using the smallest telescope Stellarium simulates, just 60×700, a common size for beginner, hobby astronomy telescopes. The view can still be improved by adding Barlow lenses and Stellarium will simulate x2 and x3. Stellarium will go smaller, with binoculars or telephoto camera lens, but this is the smallest telescope that Stellarium will simulate. This is all you need to see the Virgo Galaxy nice and clear, and this region of the sky many more galaxies. Just a little higher and to the east, still in that region of space between the end of Leo and the top of Virgo, we have Markarian’s chain. This a group of galaxies that almost form a line in the sky that can be seen all together. Moving a little bit over to the west we can see M89, a massive galaxy, very clearly. M89 may actually be spherical, a true E0. We can see another fuzzy galaxy just below it, a little bit indistinct, but this is with the smallest telescope that Stellarium will simulate, and it’s our view from the city.

If we step it up a little bit to a slightly larger telescope, we’ll see more and in more detail. Stellarium simulates specific models of telescope from specific brands, such as Celestron and Meade. This is useful, especially if you plane to buy a specific telescope, but I don’t intend to show a preference here. As an example, I will go with a Celestron C8, an 8 inch aperture telescope. With this larger telescope, we can see the M59 galaxy, a very bright E5 ellipse, and we can see the shapes of some of the smaller galaxies near it, even narrow, edge-on spiral galaxies. After zooming in this much, at this level of magnification, it is well worth zooming back out, making sure that we’re looking in the right direction and then zooming in again we know what we’re pointing at. This is one reason why many telescopes come with smaller telescopes on them, usually called finder or finger scopes. Moving your view along the sky at full magnification is risky, it’s easy to sort of get lost if you just move your view view along the sky. However, this area of the sky is so rich and so full of galaxies, you’ll often see a few galaxies close together. Although some are distant enough to be barely visible as galaxies, they will still be very fuzzy shapes distinct from stars. This is just that region of the sky, this region between the tail of Leo, ending with the star Denebola, and the head of Virgo in the star Vindemiatrix.

If we do move out into the countryside, of course, everything will look better from the countryside, but the sky is going to fill up with little object labels, as many along the Milky Way become nearly visible to the naked eye. This is unfortunately not the case for the galaxies in Virgo. In late May we can see from out in the countryside still, maybe, a little bit of sunset glow over towards the north-northwest, even as we’re coming up to midnight. However, this portion of the sky is a little bit further west, so the extra light doesn’t have much of an effect. We’re not going to have as much glow from the Sun in the south. As soon as we begin to zoom in, we’re far enough out in the countryside now that we’re going to start seeing loads and loads of galaxies get suggested to us, because it’s so dark so you can see that there’s loads of them out there. Not all of these galaxies are actually going to be visible. Being so far away, you need to be pointing in just the right place to catch distant galaxies, even if they are quite bright, as more powerful telescopes usually have a smaller field of view. We can see in this direction both the Lost Galaxy and the Lost Galaxy of Copeland. There was a galaxy discovered in this region of the sky, which was then rediscovered and assumed to be a new galaxy. All by the same astronomer, William Herschel. this is the Lost, or Hairy Eyebrow galaxy. The Lost Galaxy of Copeland refers to galaxies faint and ghostly appearance.

Nearby is M49, a really big, really clear galaxy, and another ellipse, this time E2. All of these galaxies with an M number were spotted back in the 1700’s, meaning that they are easy to see with modern technology. Some NGC galaxies can be seen around the side of M49, and even zooming in as much as I can, the images provided are just a little pixelated. Then there’s other galaxies which don’t have an image at all in Stellarium, or at least I haven’t downloaded an image for them. These are New General Catalogue numbered galaxies, many of which are only visible with very powerful research telescopes. Those galaxies are going to be out of reach to even a quite a good telescope. However, with just an 8 inch aperture telescope, the Lost Galaxy of Copeland, NGC 4535, looks fantastic great provided you have an extra Barlow lens, and it’s a distant enough galaxy that you can go up to quite a powerful telescope and it doesn’t overwhelm your view. Even with the largest telescope that Stellarium will simulate, the 16 inch aperture Meade LX200, this galaxy just fits the field of view, with some extra Barlow lenses of course. For nearby galaxies like the Andromeda Galaxy, this is overkill, only part of them will be visible at a time. However, for some of these galaxies in the Virgo cluster in this region of the sky, you need a telescope that big to really see the galaxies clearly.

With a massive telescope, the Virgo Galaxy really dominates the view, a white field almost filling the circle completely. You can however see some of the smaller galaxies down at the side, including a possibly lenticular, possibly elliptical galaxy marked as E-E/S0. These letter guides tell you a little bit about the shape of the galaxy. As I mentioned, the E is normally for elliptical. However, there are other classifications. Spiral galaxies usually have letter guides indicating their shape if their shape is known, but they also have a number indicating how they face, 1 for edge on and 5 for face on. One in Stellarium appears to be a 11, though it may be a 1I, which I don’t recognize. Irregular galaxies are noted as Im, so this may be an edge on irregular galaxy. A spiral galaxy is usually noted as SA for a normal spiral and SB for a barred spiral. There are subgroups for different kinds of spiraling and degrees of spiral. There are lots of different shapes of galaxies and quite a few of them visible out in Virgo.

Without the simulated telescope, or ocular, provided by Stellarium gives us freedom to zoom and a wider field of view, impossible with a telescope. Having a more free look around this part of the sky, we can see an edge on galaxy, marked as a 2, and barred spiral marked as SB. This one is a smaller, more distant galaxy, making it hard to see its shape. There are plenty of better examples of the shapes of spiral galaxies in this region. There are messy spiral galaxies, where it’s very hard to see the arms as they’re not very clearly defined, and grand-design galaxies where the arms are very clear and seperate. As we look around here you can see some interacting galaxies as well. Interacting galaxies are just that, galaxies that are interacting, usually through gravity. When two spiral galaxies get close together, they start distorting each other’s shapes, so it’s hard to see exactly what shapes they have or had, but neither galaxy, based on their classification as interacting galaxies, are going to really preserve the original spiral shape that they probably had.

Looking at some of the galaxies in Markarian’s chain, we can see galaxies marked at E1 and E3, different degrees of ellipsoid-ness right next to each other. We can see edge on spirals marked as 1 and 2. The Eyes are a pair of interacting galaxies that look very strange, or they look very strange to me, at least. One is NGC 4435, a barred lenticular galaxy marked as SB0, while NGC 4438 is described as a unbarred lenticular galaxy, or SA(s)O/a pec, and it may be transitional between lenticular and spiral. How exactly these galaxies are interacting is unclear, but they are likely putting pressure on each other by squeezing interstellar medium between them as they attract. We can see continuing on Markarian’s chain there we’ve got some other interacting galaxies nearby and other galaxies that are closer together but not interacting. Some of these interacting galaxies are also elliptical galaxies, so these are already quite large galaxies coming together and getting larger.

Many of these galaxies are fuzzy, or edge on, but even though I can’t see the details here, the different numbers letters used as their description tell us a little bit about what shape that galaxy would be if we could see it a little bit better. You can see that a lot of these galaxies have Messier numbers, M88 is another example. It’s an amazing looking galaxy, thanks to being really blue. This colour is a sign of lots of new stars being formed, and M88 is a classic SA spiral with many arms. We can see an SB for Spiral Bar nearby in M91 clearly a barred spiral galaxy with a clear line going across the middle. This is very different from the sort of a tight spiral or the spiral from the middle that we normally see. Another nearby blue spiral galaxy is the Umbrella galaxy. This one doesn’t have a Messier number, so it is probably a little bit harder to see, a little bit further away, but this region of the sky is full of example galaxies. I could keep looking at galaxies here for quite a while, there is just galaxy after galaxy. Despite face on galaxies being the most famous, there are some beautiful edge on spiral galaxies as well, like the Silver Streak galaxy. This one is named because of how it looks edge on, its proper designation is NGC 4216, and it is noted as SAB, or SAB(s)b. This marks it as an intermediate galaxy, not a barred SB, not a true spiral SA, but an intermediate third thing.

The richness of this portion of the sky, is pretty much unrivaled. It’s hard to look at any other part of the sky and see that many galaxies with a normal telescope. To give ourselves the best chance, we want to look at this part of the sky when it’s up in darkness, and most of us will want to look at this part of the sky when it’s up early enough at night. all of these examples are from just midnight, not 1 or 2 o’clock in the morning. For these distant objects, you really want to look at them when the Moon is out of the way, and ideally you do want to see them from the countryside. However, if you cast your memory back to just the beginning of this piece, even if you are in the city you can still see a lot of the larger galaxies. The Virgo Galaxy, for example, is visible even from the city, as long as you have a telescope.

Of course, you need a telescope for all of these things, but in a dark sky a big field of view can really show you some amazing things in this particular region. A wider field of view is usually easier to achieve with a lower power telescope. Going back down to a smaller telescope may be advisable, as a big field of view can actually be quite good for this region of the sky in particular. Not too big of a field of view of course, we don’t want to lose all the detail. In Stellarium it also helps to get rid of the object labels, and there we go, we can see that many galaxies are visible out in that portion of the sky. As long as you’re looking in roughly the right place, and as I mentioned, when you’re zoomed in a lot, it’s easy to kind of get lost. As such, it’s good to zoom out, use something of lower magnification, double check your position relative to the stars like the Denebola & Vindemiatrix, and then zoom back in.

That is just some of the galaxies that are out there in the direction of Virgo, and it happens to be a great time of year to go to look at them. If you get the chance, take it. If you get the chance to see these galaxies, go take a look at them. I hope that you enjoyed reading about them here, if you did, please do like this piece and if you enjoy this kind of content, you can subscribe to this website and my YouTube channel. Thank you very much for reading and hopefully I’ll see you back here next time.