How to chase a DSO

[JOC]

So everyone except me seems able to find and see a DSO, how do I lasso them please?

I can see M42 - I am familiar with the grey wispy colour to the background - this colouration, I assume, is what I am looking for in a DSO.  The thing is I don't know whether I'm looking for big objects that fill the viewfinder in a 32mm EP - like M42, or if I need to be in at 10mm just to get sufficient apparent magnification.

I realise its probably a case of 'getting my eye in', but what's the best way to start please?  I can find the easy one - M42.  At a reasonable evening time currently what is the next easiest one to go and find please?  The DSO browser.com website suggests that I need to looking at NGC 1980 and Andromeda galaxy as two brighter DSO's, do I need my low magnification EP's or my high magnification ones please?

[Racey]

JOC, without wishing to sound like a politician, who never answers a direct question, I'm going to start by saying "it depends what you are seeking...".

The familiarity you have with "the grey wispy colour" is good to have as a reference point. Many of the DSO Nebula certainly, to my eye, display similar "faint fuzzy" qualities...

With your scope accurately "star aligned" use the GOTO facility to get you started in the right direction... (I'm sure everyone will have their own ideas on what is a good target to aim for and, indeed, their favourites. But to be fair, it very much depends on which directions yield you better skies and unobstructed / unpolluted skies...)

One Susie and I found relatively easily and enjoy looking at, for example, is The Ring Nebula - M57. Another is M31 - Andromeda Galaxy. 

Whichever we've chosen, we make sure our eyes are dark adapted and that the GOTO has us pointed in roughly the right direction. Sometimes, something large like M31, is obvious in the finder... Other times it isn't. And when I say obvious it isn't going to leap out at you. What you're seeking is a "smudge" or traces of the grey / pale blue wispy. Essentially, something that looks different to the pinpoint well focused stars... 

If what you are seeking isn't seen in the finder, check from your star atlas or Sky Safari that you are in the right area. If not adjust in the finder until you think you're closer. Something "large" like M31 often then appears in the finder as you refine the position. Other smaller targets don't appear in the finder even though you know you are close...

When you think you are close to the area of your target, then it's eyepiece time. If, as I mentioned, it's obvious in the finder. It should be in the eyepiece if they are well aligned.

If you are confident you are in the right area but can't yet see it, give yourself time. Ensure you use patience, scan the low mag eyepiece carefully seeking that smudge... That's how we generally find the smaller or fainter targets.

If you find it, enjoy the view and maybe see if transparency and seeing will let you increase the magnification... But you certainly won't see anything to "fill the eyepiece" quite like M42. Sometimes averted vision helps too.

If after a while you still haven't seen it, make small adjustments and repeat... 

Some days things evade us because of transparency, seeing or tired eyes... Don't lose heart. Hunting them down (sometimes over days) makes the end result even more satisfying.

But you are seeking things that are almost "not there"... Think Small, Indistinct, Grey & Wispy and go for it. 

[John]

M31 is a very, very large object so your very lowest power will be the one to use. I tend to use a low power eyepiece most of the time even when serching for small DSO's. Once I have the suspect in the low power field I can examine in more detail with higher magnification if it seems warranted.

I think it is a case of getting your eye in. I found getting the right finders on the scope coupled with a star chart that I felt comfortable with (Sky & Telescope Pocket Sky Atlas in my case) were key elements in moving my deep sky viewing farward in leaps and bounds.

Edit: Most of what you see will be grey and wispy. Assume that and anything more substantial will come as a bonus

 

[cloudsweeper]

For galaxies, it's best if there is no wispy cloud about, and you aim higher up in the sky.  But DSOs also include open and globular clusters, and many of those are easy to spot even under poorish conditions.  As a general rule, search for things at low power, then when on target, increase it to suit.

Happy hunting!

Doug.

[ronin]

Really only M31, M42 and M45 will fill the 30mm eyepiece in your scope, M8 it seems is another.

Open clusters are nice but many are a repeat of either the last one or the next one, M45 is nice and bright ans I guess the most outstanding, another one close to that is the Hyades Cluster Caldwell number esacpes me, but that is likely a bit more typical. Easy to find just get Aldebaren in the scope.

Really it is practise, I would say start with the 30mm or something like a 25mm BST, simply to locate the likely blob that is the object, then move up in magnification, however likely this is only going to be up to say 80x or 100x. DSO viewing is not high magnification.

If you look at the Wiki entry for Messiers ones like M7 andM18 sort of just make a cluster. Ones like M23, 24, 25 I am not sure I would say are clusters same for a few others. They are (or at  least the image) very similar to sky.

An easy one will be M57, easy because of where it sits.

Another (globular cluster this time) will be M13 and likely M92

Galaxies are dim, M31 is too big so use binoculars, binoculars also do well for the double cluster, C14. For galaxies try the Leo triplet. For a "view" move down Leo past it's rear. There sits part of a galaxy cluster M100 and others in there. You should see say 50 small (very small) disks, they are all galaxies. But it is a bit of a cheat.

Possible trouble is Messier identified "fuzzies", and that meant a lot of open clusters, which are not greatly interesting in many cases. But he was in a way the first and so he got the easy ones. The Caldwell catalogue is a "mirror" of the Messier but they are therefore in general all dimmer and more difficult. SPM came along later.

Make a list of 5 to 10 Planetary Nebula and go find them, same for Globular Clusters and again for Galaxies.

Odd but a DSO is anything outside the Solar System, so that includes every star up there

[Moonshane]

here's my take on it

 

[SilverAstro]

There are many DSOs that dont have whispy nebula backgrounds, like for eg. star clusters. How about seeking out the Messier objects ? One nice one that is easy (!*) to find is M35. It is a pretty sprinkling of sparkly stardust on a black background I would suggest other Ms to become familiar with the different types of DSOs later but M35 is a good starter for now.

I say easy* because I think I remember you saying you have looked at Castor -  and you surely know Beetlejuice in Orion ? so imagine a line in the sky connecting the two, go half way along that line and then move off to the right and a little up, should be able to sweep it up without messing with aligning your GoTo  (just for temptation I have marked M44 The Beehive as well) :-

[JOC]

Many thanks all, looks like I have some printing to do and need another clear night when I'm not doing anything.  M35 looks like a possibility as Silver Astro notes Betelgeuse and Castor are already two firm favourites - the first I can find due to location and colour and Castor because I know its splits double when I'm on it :-D

[cloudsweeper]

Dense clusters are beautiful.  Have you tried the Double Cluster C14 in Perseus?  A real treat!

Doug.

[SilverAstro]

I was tempted to answer your "How to chase a DSO" by saying - "Shouldnt have let it out of your sight in the first place" HoHoHo, chortle

Another way to find M35 is to follow Orions upowards pointing arm from Beetllejuice, there are some nice little sights along the way and in an 8" you may even pick up a couple of NGCs nearby M35 for extras

Another reason for selecting M35 was because of your recent post on plonk&grab, I mostly do that as well

[John]

M35 has another, fainter and more distant and hazier cluster on it's outskirts, NGC 2158. Again these are low power, wide angle targets. This is how Jeremy Perez saw them using a 32mm plossl eyepiece with a 6" dobsonian:

 

[rockystar]

2 hours ago, JOC said:

So everyone except me seems able to find and see a DSO

Haha, this bit made me laugh. Every time I looked at M31, M32 was always there but it took me ages to actually see it! And M110, well that took a dark site, but now that I've seen it, i can see it from my garden!

I managed the 2 messiers of the Leo Triplet, but the third one eluded my until I went out to a dark site and a more experienced observer had to guide me to exactly where it was in the EP, that took a lot of seeing. 

And a few weeks ago, a very experienced observer star hopped (with my scope) to a very obscure galaxy (can't recall the designation), "there is is" he exclaimed, "Have a look" - nothing! I spent a good 10 minutes looking at nothing but he happily saw something there.

I've also shown M57 to a first time observer and they couldn't see it - so I'm fairly sure I wasn't being duped.

As for targets, M81/82 (bode's galaxy in Ursa Major) and M65/66 (leo triplet) are easily visible from my not great back garden skies. 

M13 is easy to find (though you don't need to with your GoTo) - but you'll need to wait for it to rise - and is a great view. 

Beehive (M44) and Wild Duck Cluster (M11) are great examples of open clusters.

 

[SilverAstro]

Ah, John has picked one of the "extra" NGCs I had in mind. It might be a good idea if while we are suggesting all thes things, to give some idea about size rel to things you already know, like   errrr  the moon !

M35 will fit in the same eyepiece as you use for the whole moon, they are of similar diameter.

[domstar]

As above, open clusters are fun and it's easy to know if you've found them. As for fainter objects like M78 in Orion, which is reflection nebula, I try to match the exact spot in stellarium with my eyepiece view and just wait, move the scope around, lose it and try to get it back and look around it. Only if I know exactly where it should be do I feel confident enough to keep looking and eventually find it. It might take 5 minutes or more and when I say exactly I mean exactly where in the eyepiece. It also helps to have it slightly to the side of the view so I'm not looking directly at it. The good news is that it's hugely rewarding and the second time with each object is so much easier than the first and the third time it appears almost immediately.

Of course our scopes and skies are totally different but finding faint stuff is probably what I enjoy the most. Have fun and good luck. I look forward to hearing about your success.

[LukeSkywatcher]

JOC, you have a Go-To scope. Let the scope find DSO for you. Look at a star chart to find what is visible and then tell the scope to go find it. I prefer to hunt them down manually. I'll use my lowest power EP (30mm) and when i detect a wisp of a smudge against the background of the sky, i'll increase the magnification slowly until i get the best view.

[JOC]

Luke Skywatcher, I thought I'd try the Goto on a wispy DSO the last time I got a good long session, and, as you suggested, I let the goto take me to where it reckoned M80/81 were - I'd heard people talk about seeing both in one view and thought that way I'd know if I found them, nothing, nada, zilch - after about 15 minutes I gave up.  Now in that situation I don't know what has failed my eyes or the goto.  What I need is a good solid location for one, that I can't fail to find, and then I will know def. that I am on target and now just waving the scope at an empty bit of blackness!

[LukeSkywatcher]

Well, the obvious ones you cant fail to find are ones you already know (M31,M42,M45). To find anything really boils down to researching their exact location on star charts etc. If your scope is properly aligned (the more stars you use to align the scope, the more accurate it will be). Most DSO are small,faint and unassuming. Its extremely easy to miss them unless you are 100% confident that they are where you expect them to be, and even then you might have doubts as to whether you actually saw them or not.

Practise makes perfect (as they say). Clusters are good targets because you will actually see them for what they are. Obviously, you also need to know where they are. The double in Hercules is about the most famous. Pretty easy to spot even with the naked eye, depending on local conditions and LP. Globular clusters (tightly packed ones) like in Hercules are easier to spot than open clusters such as M44 (the Beehive, in the constellation of Cancer). M44 is simply stunning. It better in bins rather then a scope but your 32mm EP will show it well.

Sir Patrick Moore was asked once on the S@N show what was his favourite object in the night sky. Everyone i think expected him to say the Moon. Nope, he picked M44.

Keep at it. It will all fall into place soon enough.

[SilverAstro]

43 minutes ago, JOC said:

 thought that way I'd know if I found them, nothing, nada, zilch - after about 15 minutes I gave up.  Now in that situation I don't know what has failed my eyes or the goto.

I came back here to ask you exactly that - do you know that the GoTo is taking you to the right place ! I dont trust computers !

So, we need to do a test, if you have got a known in the eyepiece such as M42 will it then take you to Castor when bidden !? and then will it take you to Beetlejuice and back to M42. If so then ask it to go somewhere else ( on a different axis to the one we just did) like M45 the Pleiades ( getting a bit low in the west now though so dont leave it till too late in the night) - you will know when you get that one. Or better, for late evening, tell it to go left anticlockwise to M44 the Behive ( cant mistake that one) or nearby M67 another cluster of stars that is bright-ish.

Till we have you on some 'not to be mistaken' open star clusters, I think we can leave the elusive galaxies like M80/81 till later ! After that we can try for some Globular Clusters.  There is a treat coming soon, M13 in Hercules, at the mo. it is a late night early morning domestically unfriendly object for laters ! So lets get the prominent open cluster DSO's nailed first perhaps

Size is sometimes tricky to describe for dim galaxies and experience 'depends'. Have you got Stellarium, it will tell you Size  if it says 30' then you know it should be moon sized and fit the same whole moon eyepiece.

 

[rockystar]

see if it swings to UMa properly too, check it out on Mizar (middle star of the handle) It's a lovely double (actually a visual triple with Alcor), and then you should be in a better place to find M81/82, I think they are pretty obvious galaxies, even in LP, and I've never failed to find them, unlike others

 

[LukeSkywatcher]

12 minutes ago, SilverAstro said:

I came back here to ask you exactly that - do you know that the GoTo is taking you to the right place ! I dont trust computers !

So, we need to do a test, if you have got a known in the eyepiece such as M42 will it then take you to Castor when bidden !? and then will it take you to Beetlejuice and back to M42. If so then ask it to go somewhere else ( on a different axis to the one we just did) like M45 the Pleiades ( getting a bit low in the west now though so dont leave it till too late in the night) - you will know when you get that one. Or better, for late evening, tell it to go left anticlockwise to M44 the Behive ( cant mistake that one) or nearby M67 another cluster of stars that is bright-ish.

Till we have you on some 'not to be mistaken' open star clusters, I think we can leave the elusive galaxies like M80/81 till later ! After that we can try for some Globular Clusters.  There is a treat coming soon, M13 in Hercules, at the mo. it is a late night early morning domestically unfriendly object for laters ! So lets get the prominent open cluster DSO's nailed first perhaps

Size is sometimes tricky to describe for dim galaxies and experience 'depends'. Have you got Stellarium, it will tell you Size  if it says 30' then you know it should be moon sized and fit the same whole moon eyepiece.

 

Yeah. Test the Go-To on objects you do know. Then if that works, tell it to find something you dont know too well. Spend a little time messing with different EP's to try to view the area it is showing you. If you dont see anything.......try another object and then see if it brings you there.

Yrs ago, i was given a Christmas gift of a Celestron SkyScout. I instructed it to locate the Moon for me (i was just testing it). The little red/orange arrows in the viewfinder had me pointing the damn thing at the ground below my feet. The Moon was right above my head. 

Never did like the SkyScout. Sold it after using it about 4 times............for an insulting fraction of the original cost.

[JOC]

Many thanks LukeSkywatcher - looks like I'll add Hercules to the list of constellations I need to learn.  Current mission is Leo and now Hercules.  Ah, I've just spotted why I won't get far with Hercules at the moment.  According to Stellarium it's almost crashed on the Northern horizon, which is non-achievable for me at my location.  Leo is available though I def. found it the other night, but I need Stellarium to help me find it.  Those I already know without help are the easy ones - Ursa Major, Orion, Casseopia (the big W shape - yes?), and I am in the odd situation of normally being able to sort out Castor and often Pollux yet can't determine where the rest of Gemini sits (which is slightly annoying as I'd like to recognise my own star-sign), I can usually sort the little dipper (because that's got Polaris on the end of it and I can find Polaris - at least by eye - different kettle of fish in the rotten finder-scope - from UMa), if I can see Orion I can find Aldebaran (which is a huge big golden 'glowy' star) and I can follow it through and land on Pleiades.  So I can see a good few stars that I know, though my options at the moment diminish as Orion disappears - which I why I need to get Leo sussed.  As you say I really need to check that the goto can find things that I can confirm.  As you know I haven't had too many sessions to even use it so far.  On a couple of those sessions I am sure it has worked, on others I've not been so sure - it's all down to me being able to correctly identify with my eye and then correctly find once magnified the right stars to calibrate on.  As you know Polaris is one of those that is easy to find by eye, but one I find difficult to locate in the finderscope.  However, a non-magnified RDF turned up in the post today - the Skywatcher one.  I sometimes shoot clay pigeons and the notion of the RDF makes sense in terms of looking beyond it, so hopefully it will give me an alternative to the magnified finder-scope which I might find easier to use - I think if I can reliably get the telescope on Polaris and Betelgeuse and can be sure of the calibration that it will then work OK - on the occasion I've been sure of the locations it has appeared to work goto wise subsequently, it's just my lack of knowledge that is defeating me at the moment.  I am so grateful for everyone's help.  Now if you can all just do anything about the cloud to give me a chance to practice that would be  great!

[LukeSkywatcher]

Cassie is the big W. Plenty to see there. Its a great easy way to find M31. Leo is a great constellation/sign post. Think of it (the head of Leo) as a backwards question mark. Head right from Leo and you are into Cancer (M44-Beehive cluster). Castor and Pollox are also the only 2 stars in Gemini that i can notice/make sense of. As you say "it's just my lack of knowledge that is defeating me at the moment". That's ALL it is.

P.S.~call me Paul.

[rockystar]

Have you worked out to get Stellarium to look like this? I find it helps a lot.

[Stu]

As has been said, objects vary hugely in scale, so it is essential to have a good understanding of this size in order to stand a chance of seeing them properly.

Looking at the North America Nebula at high power is likely to show you nothing, looking at the Ring Nebula at low power will give similar results.

Some objects shown here with Telrad circles overlaid to show the scale. The circles are 4 degrees, 2 degrees and half a degree.

The likes of M31, M45 and the Veil are large and need low power and a wide field to show in context, first three images. Globs and planetary nebulae are generally much smaller and need power to see, next four images show these at different 'powers'

[Astro Imp]

As you know I have the same scope as yourself but haven't had the opportunity to get much use from it yet as I returned the mount for being over noisy. Good news I today received a brand new mount and hope this will prove better.

That was by-the-way, what I wanted to impart was on the one occasion I used the GOTO I found it landed me spot on the objects I told it to find. I chose objects that I new and would be easily visible. There was no point chasing faint stuff as the transparency was awful that night so apart from M42 I stuck with easy open clusters.

FYI I took the trouble to align the starting position as accurately as possible by finding north by pointing at Polaris and then bringing the optical tube down to the zero index mark.

As soon as I get a good night when I can do some observing I will be sure to post.