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Which are the tricky Messiers?


kerrylewis
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I've noticed that even some obviously experienced observers are sometimes a dozen or so Messiers short of the full complement . Which are the difficult ones? I've only recently started to log them and from my garden it seems that the Sagittarius ones aren't going to be easy.

Kerry

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What's "tricky" probably depends on where you live and what sky conditions you usually have. Even with dark skies for those of us in the UK the really tricky ones are probably those that are close to the southern horizon during the summer months. Several of them are quite faint, a few don't even make ten degrees above the horizon and there's only a short window of opportunity to see them, both in terms of when they're in the sky and when the sky is dark enough. The further north you go the harder those ones are.

James

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Several are simply not visible at times, M42 at present being a prime example.

Low ones are always difficult and if you miss them the wait could be a year more or less.

Must admit there seems to be more messier marathons in the US hen appear to be here. They seem to be a familiar event there in March and well attended, a star party with a good excuse. I think there is one here at NLO and that is it.

Also the US and Canada have certificate programs, a common and obvious one being the Messier objects. Here it comes across as something that people do with not too much urgency or final aim other then to tick them off.

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You have to remember that almost everywhere in the mainland USA is further south than anywhere in the mainland UK, so those more southerly ones are visible higher in the sky for a longer period of time. That makes a Messier marathon far more viable.

James

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Agreed that the most southern ones are difficult from middle England. Others that can give trouble due to their large size and faintness are M101 and M33.

You'll have a search for M76 , M109 and M97with any sort of light pollution. The others come around with the seasons and clear skies,

Nick.

Edited by cotterless45
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Ones with the lowest surface brightness (therefore hardest at light-polluted sites) are M101, M33, M74 and M110. M74 is smaller than the other 3 which adds to its difficulty, so it's often considered the trickiest of all the Messiers. But all of these are easy from a UK dark site.

Ones at lowest declination (most southerly first) are M7, M69, M70, M6, M55, M54, M62, M83. These are all at a declination of -30 degrees or lower, so will be near (or even below) the horizon for UK observers.

I've seen all the Messiers, but not all from UK. Most southerly I've seen from UK is M83, which rises about 5 degrees above my horizon. M7 theoretically rises about half a degree above my horizon, i.e. is impossible. I viewed the most southerly ones with 15x70 binos or an 80mm short-tube refractor during holidays in southern Europe.

To get your horizon limit, do "latitude - 90". I'm at 55N so my limit is 55-90 = -35, hence an object at -30 will rise to 5 degrees above horizon. That will be when it is on the meridian, i.e. due south. So in considering your horizon limit you also want to consider any obstructions to your southern horizon. Altitude affects horizon: a mountaintop will let you see a little further south than a sea-level site at the same latitude. But it might get a bit windy up there.

The most southerly Messiers are in Sagittarius and Scorpius, hence are best seen in summer when nights are shortest and skies are lightest. This adds to the difficulty for observers in the more northern part of UK. In southern Europe they can be seen high in a dark sky, and are easy targets.

US observers are at a more southerly latitude than UK ones (New York is at about the same latitude as Madrid), so "Messier Marathons" are popular over there, during the window in March when all of the objects can be seen in one night. A complete Messier marathon might be possible from the southernmost part of England, but I don't know of anyone who's ever succeeded. At Lizard Point in Cornwall, M7 will rise to about 5 degrees above horizon.

Messier list ordered by declination:

http://messier.seds.org/dataDec.html

Edited by acey
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Despite the low declination, they are all visible from the UK if you choose your moment. I've seen them all from home and I know others have done so from the south coast. So you don't absolutely have to go to a more southerly country, but the views will be considerably better if you do.

James

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M101 and M110 have thus far eluded me, but I don't feel so bad now understanding more about brightness and size of some of those objects, how all that works a bit more since I started, and only having a modest amount of aperture brings an extra challenge. They will be mine and bagged one day, so I do not worry, I don't think the are going to vanish anytime soon in my lifetime :D When I wrote that it somehow reminded me of this scene :)

Edited by AlexB67
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M101 is difficult? I now feel strangely smug for having succeeded in finding it my little telescope. Admittedly this was in darkest Pembrokeshire - I wouldn't even chance it from Bushy Park. I suspect that M33 is one that will have to wait until our trip to the New Forest / Exmoor in October.

From London most of the Messier objects in Scorpius and Sagittarius would be extremely challenging. I'm going to attempt to find M8 once August comes around with some darker skies (Maybe clear ones?), but I expect at some point I'm going to have to try to persuade my lovely wife that a holiday in Southern Spain is in order. I went to a wedding there a few years ago in August and was pleased to see Scorpius and Sagittarius rising very high into the sky. This was in the village of Gaucín in Andalucía.

DD

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M101 is difficult? I now feel strangely smug for having succeeded in finding it my little telescope. Admittedly this was in darkest Pembrokeshire - I wouldn't even chance it from Bushy Park. I suspect that M33 is one that will have to wait until our trip to the New Forest / Exmoor in October.

DD

I would imagine that the darkest skies you mention would have made all the difference to see M101, though not sure what that is like not having used my scope under dark skies yet. I can imagine though, I've little doubt that people can buy the biggest light buckets they like, but dark skies are hard to beat, of course having both, even better. :) I'd say my skies around here are NELM 4.5 perhaps, may be 5 at best, I never checked precisely, seeing I can't change the skies anyway :D

My folks got a house in South West Ireland, it gets really dark there. You cannot even see where you're walking without a torch. I'll be visiting there in Sept some time. A lot of those object I cannot see where I am now would be easily bagged there I am expecting, clouds permitting anyway, looking forward to that. The number of stars visible to the naked eye is unreal there, NELM 7 I suspect no bother at all on a half decent night, that is going to be a big jump in what can be observed :)

Edited by AlexB67
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Lucky you. I've observed from VLM 7 skies. The only way to describe the views is breathtaking.

Where you able to identify individual mag 7 stars? Where was the location?

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Laying on the ground with a tube to sight through. I was able to plot some individual 7th mag stars at the zenith. I'm actually wondering if this could be bettered there on an exceptional night by someone with keener, younger eyes than me.. I will have another look next time I'm there. I find using a sight tube can really help pick out faint stars right at the limit of visibility. It seems to concentrate the eye better. By cutting down the number of available targets its easier to zero in on the star you wish to try and plot.

Not going to give the exact location but it was in mid Wales at a fair altitude.

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Thanks for that info Steve. By looking through a tube you're eliminating much of the sky background, replacing it with the darkness of the tube, and this makes fainter stars visible. The classic experiment was by Curtis, who viewed stars through a small hole in a dark screen and found he could just glimpse ones down to about 8.5, though his limiting magnitude for stars seen against the sky itself was 6.5. This raises again the question of how limiting magnitude should be defined: I'm always a bit sceptical of any claim beyond about 6.5, and not too surprised to learn that in this case it was achieved under special viewing conditions. Sounds like a great site in any case - don't blame you for keeping the location to yourself!

Edited by acey
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It is an interesting topic I've been thinking about recently too. I can see the value in SQM-L measurement in a way, or so it seems to me, since the figures are per arc sec 2 as well. In a way NELM observations leave more room for interpretation in that sense.

When we claim the magnitude of a telescope it is defined around a certain set of parameters such aperture, and so on, but the baseline quantity NELM does seem a slightly woolly concept to me, or perhaps I am missing something. To me it seems SQM is a more quantitative figure to talk about, NELM a more subjective one.

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When I started observing about 18 mth ago, I'd spend days (if not weeks) finding a target. while frustrating at times, it was also very rewarding. Then around july last year I had a forced "holiday" back in Oz so I got myself a 130 heritage for the stay. I was then faced with a very different problem... I could hardly look at a chunk of sky around sag/sco without seeing a messier. It took me quite a while to work out which was which. I also remember the first time I went "outback". I made sure that it was a moonless weekend and all day long it was nothing but blue skies, then as it was still light I went in for tea and when I returned it was pitch black. I was furious at the white clouds that had drifted in during my absence......only to realise later that the clouds were in fact the milky way. If I held my hand about 6" from the ground there was a definate shadow cast from the milky way. Whilst I seriously doubt I will ever see skies like that again, the memory will live with me forever...

Sorry for the reminising..................I am yet to find m33 visually :)

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  • 1 month later...

I saw M74 for the first time last night with my 12" scope. I live in a fair amount of LP so it was very faint and bordering on 'not there' even with this aperture. the fact it's a face on spiral spreads the light it has over a wide area making it appear even fainter. I was having to roll my eye around constantly to see it with averted vision and rocking the scope helped too. I repeatedly found and relocated it in the same place which is how I tend to confirm new stuff. I think with this I went to Aries and back about six times in all.

the position is easy enough but it's certainly a tough one from home. I hoped it may be a little easier with the 16"; I'll try soon and also from a darker site. it will be on my PSP list for sure.

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I was spoilt with my old scope as it had goto which is great for seeing lots of stuff but you don't really get to learn the skies. Upgraded to a 300mm skywatcher dob with tracking only. Forced me to learn what's up there and where. Finding Messier objects becomes far more rewarding when you find them for yourself. I have added a telrad to my scope which helps to identify exactly where some of the faintest fuzzies are. Finding my way round the Leo Virgo galaxies in the spring was so satisfying !

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  • 1 month later...

I saw M74 for the first time last night with my 12" scope. I live in a fair amount of LP so it was very faint and bordering on 'not there' even with this aperture. the fact it's a face on spiral spreads the light it has over a wide area making it appear even fainter. I was having to roll my eye around constantly to see it with averted vision and rocking the scope helped too. I repeatedly found and relocated it in the same place which is how I tend to confirm new stuff. I think with this I went to Aries and back about six times in all.

the position is easy enough but it's certainly a tough one from home. I hoped it may be a little easier with the 16"; I'll try soon and also from a darker site. it will be on my PSP list for sure.

That makes me feel better. I've just spent about an hour and a half checking and re-checking I was in the right place, scanning back and forth, tube tapping, eyepiece changing and generally going mad.

I dropped down a bit and found Cetus A (M77).

I checked I could see M33.

And eventually I gave up - cold & with backache.

But I did find Neptune earlier so still a good evening :laugh:

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I have never seen any of the [many] ones in Sagitarius.  They never get above the houses to the south of my garden even when we have a good summer night.  These are on my list for next year and I will camp on the South coast with my daughters if needs be to see them

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I will camp on the South coast with my daughters if needs be to see them

It's well worth it. I made a special effort this summer (twice, in fact), 'cos I'd seen how many Messier objects there were there, and it was fantastic. I got a good, clear, dark night both times - and there were so many nebulae. I managed to catch M6 and M7 poking above the horizon at the beginning of July, which left me chuffed - it's downhill from there, right?

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Sagittarius in my short time in this hobby , is the most amazing area of the sky I've looked at . Full of goodies. I sat in a farmers field last sept, just me , scope and a bottle of beer. I knew if I got a half decent southern view I'd get to see what this teapot has to offer. And really was worth the effort . M 2 glob . Was fantastic, I'd imagine that if it was higher in sky it would out do m3 or m13.

Of the messiers I've seen , I found m108 a hard task , took half a dozen attempts to finally make this one out. And I've not seen m109 either ,I've tried a few times. However as already said , sky conditions are often crucial for fuzzies. And from a town or city your always going to have a hard time.

Edited by rory
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