Orange Smartie

Hello. My son recently bought me an OIII filter for my birthday, which was very kind of him. It was supposed to go on a larger telescope (10 inch dob) that I have on order but probably won't come for a couple of months yet. I realise that these filters are somewhat specialised bits of kit, but it would be nice to have a go at some targets, even in my smaller (6 inch) dob. Any recommendations? I've already had a look at M42, the Clownface/Eskimo nebula (very faint in the small telescope) and I fancied I could see a difference between the background darkness within the Rosette Nebula and the surrounding area. That's about it though. What's a good "must see" visual target? Pete

How about some multiple stars? Beta monocerotis and sigma orionis, for a starter.

You should be able to separate some double or multiple stars. They may not seem the most dramatic target, but fascinating if you get a pair with different colours - you could look into why they are different. Also the fact that the stars are orbiting each other (and that many stars are binaries, unlike our own) may be of interest if your daughter has an enquiring mind. One of my personal favourites is Almach, which has a very distinctive colour difference between the primary and secondary component. Start with some easier ones - some multiple stars are really close and require very good seeing conditions and a big scope.

Really cool that you managed that pic with your phone! Yes we are lucky. I showed my wife a few objects the other week including the Leo Triplet of galaxies. The conversation went a bit like this: Me: "Can you see those three faint smudges". Mrs S: "Yes". Me: "Those are galaxies". Mrs S: "Like our galaxy?". Me: "Yes". Mrs S: "What, whole other galaxies?". Me: "Yes". Mrs S: "Wow!". Wow indeed!

You may well have seen this recommended elsewhere, but if not, you could also take a look at this list of objects that are visible from light-polluted skies: https://las-astro.org.uk/docs/Loughton_List_v2_0.pdf Thanks to @Tiny Clanger for drawing this to my attention.

Having had 1 dog (Lakeland terrier) and 2 cats during my married life, I like both and for different reasons. Our cats have both been quite "dog-like", especially our current one, Frank. He has taken to accompanying me out for my observing sessions and will happily sit next to me while I'm at the scope.

That's very exciting! You should be able to observe loads of stuff with that, but remember that what you see (and whether you can see it at all) will depend on multiple factors including light pollution, phase of the moon, how high the object is in the sky etc). I dont say this to discourage you, but to encourage you to pick your targets depending on where you are and how the conditions are on a given night - as recommended before, Turn Left at Orion is very helpful in making the choices of what to look at. Best of luck, I look forward to hearing how you get on! Pete

Thanks for sharing this John. I only managed a very short session, in between clouds, but got a few galaxies in my 6 inch dob. Leo triplet and M81/82 were very easy. I also got a triplet west of the Leo triplet, arranged as an obtuse scalene triangle. I think they were M95/96/105 - first time I'd seen these three.

Hello and welcome. No experience of them, but a lot of people use the Rigel or Telrad finders. I think the Telrad may be too big for your scope, but I'm sure someone else will be along to comment. They are essentially like red dot finders, although with rings rather than dots. I have a set of BST starguiders that I bought to improve my viewing experience with my 150p dobsonian (I got 25mm, 12mm, 8mm and 5mm). They are great eyepieces for the money. If you wanted to save a bit of money you could get a 2x Barlow lens, which will give you twice the magnification for a given lens - so for example, an 8mm would give you 81x, assuming the focal length of your telescope is 650mm; with a Barlow that would be 162x.

So I have checked online and it looks like the finder is adjusted with two screws against a spring-loaded button. Use a low power eyepiece (25mm) to aim the main scope at a terrestrial target. Don't point your scope at the sun!!! Adjust the two screws on the finder until the finder is centered on the same object. Good luck!

Hi. Apologies if I've missed this from your post, but it sounds to me as if you haven't actually aligned the finder along the same axis as the main scope. As @dannybgoode suggests, you'd need to adjust the finder itself, having first pointed the main scope at some terrestrial target. Once you've done that, the finder should have a series of screws that you would adjust in and out to ensure that the finder itself is exactly aligned with what you can see through the scope. It's possible to set up the alignment at night but if you use a celestial object it will have an apparent motion relative to you, because of the earth's rotation, so you're unlikely to get it as accurate.

Thanks for the heads-up on this @Second Time Around. Just bought one of these and it looks excellent.

I haven't even thought about M92 before, but now you mention it, I'm keen to look! It's on the list.

Thanks. I was on the verge of telling myself it wasn't worth it, but so glad I waited.

Thank you! It's a heritage 150p dobsonian.

A clear night was promised for yesterday and I was full of eager anticipation to try for some new objects. As often seems to be the way, the cloud persisted a lot longer than I had thought it might; looking out at about 11pm, thin cloud was visible pretty much across the whole sky. Not wanting to stay up late only to be disappointed, I almost shelved my plans for an observing session, but I thought I would hold on just a little bit longer to see how things developed - and I'm so glad I did. By about 11.25pm, the cloud had all but cleared and the moon, not yet up, was not around to spoil the party. I had a little self-imposed pressure, therefore, to crack on with observing (or at least trying to observe), many of the objects that had eluded me under brighter skies. First, to get my eye in, I turned my scope high to the East and Canes Venatici, to split Cor Caroli - an easy split in my 12mm eyepiece (about 63x). Then, since Leo was sitting to the South and high, to the Leo trio. I really just pointed my red dot sight between Chertan and Iota Leonis and there it was, all three galaxies, very clearly visible albeit with little detail to see. A good start! To Cancer next and I spent some time comparing the M44 and M67 clusters, the former appearing larger and "loose" and the latter much more compact. Took a quick glance at Tegmine - split to look like a "double" at 5mm (150x), but I was unable to resolve the brighter part in to two separate stars. Iota Cancri split easily at 30x, looking much clearer at 63x; a yellowy primary with a blue-white secondary. Back to Canes Venatici and I picked out M94 and M63 - 94 appearing to my eyes as a fuzzy ball and 63 like a broader smudge, with a bright spot (star?) close by. Since I was there, I thought I'd try for M51 and there it was, a larger disc with a smaller spot of brightness close by. Finally, in Ursa Major, I took a look at the large, but very faint disk that was M101. Hercules was now quite visible and the "keystone" high above my horizon. M13 was dead easy to find, appearing as a large, tight, fuzzy ball. It stood up to a higher power (up to 150x) no problem, and with averted vision I was beginning to grasp just how many individual stars must be sitting in that cluster. As I wrote in my notebook, "amazing!". By comparison, M3, between Cor Caroli and Arcturus was a little less impressive - perhaps I felt a little sorry for it, living in the shadow of its more impressive cousin - "still good", I wrote. I next took my first look at Bootes. The split of Epsilon Bootis eluded me, even at 150x. I had the feeling that there was a double to be seen, but I think the seeing was just not good enough, with the star boiling and changing shape as I watched. Mu Bootis was an easy split at 30x and Xi just split nicely for me at 150x - a yellow primary and an orange secondary. Coma Berenices was my final target for the evening. 24 Coma Berenices, a nice yellow/blue double, nicely splitting for me at about 94x magnification. My last two new objects were M53, a globular cluster appearing as a small tight fuzzy blob and the Black Eye Galaxy, M64 - very easy to spot, but without a lot of detail. After taking one last long look at M13, I concluded a fairly short, but very productive session, many of the targets being completely new to me and many, like the Leo Trio, only having been dimly visible beforehand. Just goes to show how much the viewing conditions impact what can be seen. Pete

If you have a PC, you could always try Cartes Du Ciel, available as a free download. See: https://www.ap-i.net/skychart//en/start Edited to say there is a Mac version too.

I have the Cambridge Star Atlas (not the double star version). Its good, but as others have said elsewhere, I'm not sure how robust it is really. Guess I'll find out! The text size is also quite small, which might be a problem if your eyesight isn't very good.

Hi Charles and welcome. Fellow beginner here. If you haven't already got it, I'd strongly recommend buying a copy of "Turn Left at Orion". It will help you become more familiar with what's up there in the night sky (clouds, currently for me) and perhaps most importantly, what everything will look like in your telescope. The examples they give are all shown from the perspective of a small refractor and an 8 inch dobsonian, so you'll know exactly what you should be seeing, assuming the viewing conditions are suitable. You've probably already noticed that this forum is the most helpful and friendly and you shouldn't be afraid to ask any questions. We all started somewhere! Pete

Just to chip in here regarding collimation - my heritage 150p came with a collimation cap included, so a 130p might do too. Pete

Thanks all. @wookie1965, yes it is a 150p. I'm so used to looking at clusters like Pleiades and M35 that I expecting a brighter object in a wider area! Clearly that is not what I will experience with this. I'll take a pop again and try with the 5mm or 8mm. Pete

Thanks both. I'll take another look, maybe at the end of week when the skies will be darker.

It was in a 6 inch dob.

I only managed a short session last night, but one of my targets was NGC 7789 (Caroline's Rose) in Cassiopeia. I can see where it should be from my star atlas, and at low power I would imagine that with a 2° field of view I should be able to pick it up even if I'm not exactly centered on it. I thought I saw a very faint fuzzy area, but I'm not convinced I'm looking at the right thing. Is this a cluster that needs a very dark sky to observe it properly? Pete

Thanks for this tip. I managed to find this in spite of the moon. Primary looked yellowy white to my eyes, with a blue secondary. Lovely!