Open Clusters and Uneven Doubles - 21st February 2019

[Stu]

With Mrs Stu and little Stu away for a second night, I was unexpectedly presented with a second night of clear skies. Too tired for a late session, I got out before 7pm and had a really good 3 hours with the Mewlon 210, probably my most enjoyable session for quite some time.

The skies were not that dark, even before the moon rose, and the deepest I was going with the scope was around mag 11, perhaps a smidge deeper. Seeing was pretty variable, but good enough to have some enjoyable views of doubles down to about 2" separation but I was struggling below that.

Two reasons for the enjoyment. Firstly the scope is performing very well, giving very contrasty views and lovely sharp stars. The diffraction spikes are very noticeable on brighter stars, and are something I'm not that used to, but I'm able to look beyond them to what is actually visible, and that is highly rewarding. There is mirror shift when using the main focus, but I have a secondary focuser fitted which allows very precise fine focusing. I only have to use the main focuser when switching between eyepieces with significantly different focus positions.

The second reason for enjoyment is the mount I'm using now. I searched for a good GP-DX for a long time, and finally found one quite recently. I have it mounted on a Skywatcher pillar which is very stable (held down by bags of gravel!), it is driven using a Skysensor 2000PC controller which connects to SkyFi and onwards to Skysafari which is where the real joy begins. The gotos are very accurate, and I'm able to scan around the constellations in the app and pick out objects to view which I would never normally consider. Sometimes they are disappointing, but quite frequently I come across gems that are well worth observing. The Sksysensor remembers its alignment even when switched off, so I can be up and running very quickly.

I now have a selection of eyepieces which suit the Mewlon very well. 56mm Meade Plossl, 40mm Paracor 65 degree, 30mm 82 degree ES, 20mm APM 100 degree, and Docter 12.5mm 84 degree. These give me x43 with a 4.9mm exit pupil, x60 with a 3.5mm EP, x80, x120 and x193 which is a great spread, although the APM tends to hog the focuser.

So, what did I see? The answer is quite alot. I added them to an observing list in Skysafari as I went, and then made notes on them today as a reminder. I think they are accurate recollections!

- NGC 225 Small Open Cluster that benefitted from the higher mag of the 20mm
- St 24 Open Cluster, with a tiny little triple in it including blue star Lamont 1 in the centre, hard to resolve the three but managed with averted vision
- NGC 129 Open Cluster, lovely little double in the centre
- HD 236449 and HD 236446, nice pair of reddish stars near NGC 129
- NGC 663 Bright Open Cluster

- NGC 457 My old favourite, fun as ever

- NGC 637 Small and subtle
- M 52 Bright Open Cluster, small, best in the 20mm
- K 14 This was a great one, K14, NGC 133 and NGC 146 all in the field of view together. NGC 133 a clear line of 4 stars, the others more subtle but identifiable
- Be 4 Very subtle, small group of mag 9.5 to 11 stars, more would be visible under a dark site
- K 16 Even more subtle, mag 10 to 12 stars, averted vision needed to pull out anything
- Iota Cas Lovely double, mag 4.6 and mag 6.9 with 2.6" separation
- NGC 7789 Caroline's Rose. Very subtle under my skies, needs darker skies to look at its best
- Sigma Cas Another lovely uneven double, mag 4.9 and 7.2 with 3.1" separation
- NGC 7686 Brighter open cluster with mag 6.2 orange HR8925 in the centre
- NGC 281 Pacman Nebula Could not see the nebula, even with a UHC filter fitted. Perhaps should have dropped to the 56mm for the larger exit pupil
- NGC 659 Very subtle and small, brightest stars below mag 10
- St 2 Large OC, filled the FOV of the 56mm
- NGC 869 & 884 Double Cluster Beautiful as always, only one cluster at a time in this fov
- HD 16068 Faint, widely spaced double. Orange Mag 7.4 and yellow 9.9 with 35" separation. Nice none the less
- Theta Persei Another nice uneven double, mag 4.1 and mag 10, similar yellow-white with 20.4" separation
Beta Mon Needs no introduction, beautiful triple, 2.6" and 7.1" separation, subtle blue white
- Cr 106 Open cluster, quite bright but wide spread, a few brighter stars
- Wasat Lovely uneven double, mag 3.5 and 8.2 with a 5.4" separation, yellow white
- Al Kirkab Another uneven double! Mag 3.5 and 10 at 7.2" yellow, subtle orange
- Theta Aurigae And again, another even tighter uneven double, mag 2.5 and 7.2 with a 4.2" separation
- M 37 Fantastic in the 20mm, looked quite dense and compact, with brighter stars than M38
- M 36 Pinwheel Cluster Smaller and more sparse than the other two
- M 38 Starfish Cluster Looked large in the 20mm, mostly mag 9.8 to 11 stars visible, distinct shape with 'arms'
- NGC 1907 Small and very subtle, darker skies needed really
- NGC 1931 Couldn’t quite work this one out, a small area of either closely packed stars or nebulosity. Need to revisit
- NGC 1893 Relatively large open cluster, much more distinct that 1931
- NGC 1778 Small and subtle, a little group of faint stars
- NGC 1857 Another small and subtle one, a little more interesting because of the mag 7.4 HD34545 in the centre, nice orange colour
- M 41 Total accident this one, meant to head for M42 but typed in the wrong number ??,  but luckily this is a new Messier for me. Large, lovely cluster with a mix of different coloured stars. Will come back to this again
- M42 Orion Nebula lovely as always. Plenty nebulosity with structure visible despite the bright conditions. E star showing well in the Trap but seeing not good enough for F

- NGC 2169 A session wouldn't be complete without the 37 Cluster. I love splitting the tiny double in top cover of the 3 (I think it's the 3 anyway, will check next time)
- Algieba Cracking bright double, mage 2.2 and 3.6 at 4.7" separation
- M 44 Beehive Cluster Too big for the Mewlon really, filled the fov so it was hard to get the context of it as you would in a wider field scope. Eyepiece full of stars though!
- M 67 Smaller and more subtle, but better suited to the Mewlon, quite compact OC with plenty of faint stars

So, thanks for sticking with this (if you did! ??), great to have a rewarding and fun session, and to actually see a good range of objects. Even under skies that are not that dark it is possible to enjoy the hobby.

[Paz]

Wow that is a mega list of objects in one go!

[Mark at Beaufort]

Stu what a session and to remember all that information. Clearly the Mewlon 210 is a wonderful scope.

[scarp15]

Great read, lots of lovely targets, interesting scope. The Pacman, I use an OIII, one more so for a dark sky, when becomes distinct and quite bright, low power but not necessarily largest exit pupil 3.5mm - 4.5mm quite adequate.

[Astro Imp]

That sounds a lot of fun, you've certainly most of the opportunity to get out.
Thanks for all the info. I really enjoyed the read.

[Geoff Barnes]

Incredible haul in such a short session Stu. you truly are an Astroholic! ?

I'm a little surprised you couldn't see the F star in the Trap with such a high quality scope, I seem to see it really easily with the 12 inch Dob. I wonder if it's to do with your smaller aperture (8" ?), or the fact that you're viewing it at a much lower elevation? Or maybe a combination of the two, or even more factors?

I'm hoping to get out here tonight and see if I can tag a few of those gems you've listed.

[Stu]

7 hours ago, Geoff Barnes said:

Incredible haul in such a short session Stu. you truly are an Astroholic! ?

I'm a little surprised you couldn't see the F star in the Trap with such a high quality scope, I seem to see it really easily with the 12 inch Dob. I wonder if it's to do with your smaller aperture (8" ?), or the fact that you're viewing it at a much lower elevation? Or maybe a combination of the two, or even more factors?

I'm hoping to get out here tonight and see if I can tag a few of those gems you've listed.

Thanks Geoff. I'm sure the lack of F is down to a combination of factors, mostly seeing conditions as I have to observe over houses but also LP too, I think it gets swamped. Obviously aperture helps, and the higher altitude it reaches for you will make the most difference I think.

I need to get the scope down to our local observing site where we can observe over fields and the seeing should be better.

[Saganite]

What a fabulous session Stu. 

 

[mark81]

Great report Stu - and Three hours!? That beats my longest session by atleast an hour (although, two hours with an ST80 can feel like a lot longer) A real nice selection of clusters there - great read...

[Stu]

5 minutes ago, mark81 said:

Great report Stu - and Three hours!? That beats my longest session by atleast an hour (although, two hours with an ST80 can feel like a lot longer) A real nice selection of clusters there - great read...

Thanks Mark. I have done all nighters before at star parties, and will spend hours looking just at Jupiter when it is well positioned if there is something interesting going on like a GRS transit or multiple moon/shadow transit. During the 2015 Lunar eclipse I was up all night, and then tracked Jupiter well into the daylight. Great fun, and lovely to watch the world wake up slowly

[Guest]

All that in three hours, wow.  Need to get my sessions organized a bit better. 

Thanks for the great list. ?

[Stu]

8 minutes ago, AstroCiaran123 said:

All that in three hours, wow.  Need to get my sessions organized a bit better. 

Thanks for the great list. ?

I wish I could claim organisation for this. Driving the scope through Skysafari makes it so easy to scroll around and identify likely targets, then just click and goto it. A little lazy, but I find it a great way of observing.

[Littleguy80]

Ace report, Stu. The double in the 37 cluster is indeed in the 3. I saw it for the first time this week after you recommended it  Like Iain, I use an OIII for the Pac-Man. 

[John]

Very nice report to read Stu ?

I've been in central London for the past 2 nights so have seen no stars at all despite the clear skies !

The Mewlon sounds a great scope. I'd like to try one for myself someday.

[F15Rules]

Fabulous Stu. I've never used Goto, just star atlas and finder, but I can see the appeal when you can use tech to find and view so many targets in one session.

A great read, thanks?. And the Mew-lon sounds pretty much a purr-fect scope!

Dave

[F15Rules]

...and I found this photo online of some lucky person who has a Mewlon and an FS128 on one rig..

Now that would make an interesting comparison?..

Dave

[Stu]

35 minutes ago, F15Rules said:

...and I found this photo online of some lucky person who has a Mewlon and an FS128 on one rig..

Now that would make an interesting comparison?..

Dave

 

That must be a great fun setup to use Dave! Not sure which would give the nicer views.

I found this review very interesting before I bought my mewlon.

https://www.cloudynights.com/articles/cat/user-reviews/takahashi-mewlon-210-review-r2713

[Stu]

55 minutes ago, F15Rules said:

Fabulous Stu. I've never used Goto, just star atlas and finder, but I can see the appeal when you can use tech to find and view so many targets in one session.

A great read, thanks?. And the Mew-lon sounds pretty much a purr-fect scope!

Dave

I do enjoy star hopping under good skies Dave, but it's a bit of a slog under LP so a good goto can really help you see stuff you would just never find otherwise. Seeing it in Skysafari too means you don't have to remember which object reference to look for or might be worth finding, it is right there on the screen, just a tap and you are there 

[F15Rules]

Also on CN, a good few people preferred the frac, but a lot also said that they preferred the Mewlon, especially on deep sky, which I guess you would expect given the additional aperture of the Mewlon.

The biggest factor people seem to comment on is the ease of acclimatisation with the FS128, but  when the Mewlon is properly stabilised it can then pull away..

Dave

[Geoff Barnes]

I had a great session here this evening visiting all the best targets in the vicinity of Orion in the north and Eta Carina in the south, but I came away with one very special find that was new to me, and I don't think was on your list Stu, the beautiful double known as the Winter Albireo or h3945 or even 145 Canis Majoris. Have you seen it? It's nearly directly overhead here at the moment so very clear and bright, orange main star and pale blue secondary, just gorgeous, much better than Albireo which hugs the northern horizon here and thus is a bit dim.

[Stu]

28 minutes ago, Geoff Barnes said:

I had a great session here this evening visiting all the best targets in the vicinity of Orion in the north and Eta Carina in the south, but I came away with one very special find that was new to me, and I don't think was on your list Stu, the beautiful double known as the Winter Albireo or h3945 or even 145 Canis Majoris. Have you seen it? It's nearly directly overhead here at the moment so very clear and bright, orange main star and pale blue secondary, just gorgeous, much better than Albireo which hugs the northern horizon here and thus is a bit dim.

Thanks Geoff. No, that wasn't on my list and is one I would love to see, just didn't think of it at the time.

I'm struggling to find it on Skysafari. I can see a double at what seems to be the right location but the secondary is the wrong colour.  Need to do a bit more digging, but thanks for the heads up!

[Stu]

On 23/02/2019 at 23:31, F15Rules said:

Also on CN, a good few people preferred the frac, but a lot also said that they preferred the Mewlon, especially on deep sky, which I guess you would expect given the additional aperture of the Mewlon.

The biggest factor people seem to comment on is the ease of acclimatisation with the FS128, but  when the Mewlon is properly stabilised it can then pull away..

Dave

I'm sure the 128, or other similar 130mm top class refractors are better in a number of ways, better star shapes, more stable images, no diffraction spikes amongst them. However, as you say, when stabilised well, the additional aperture of the Mewlon will come into play. The secondary support vanes are thicker than on a newt say, but the benefit is the great stability and ability to hold accurate collimation. The small faint stars I'm seeing are beautifully resolved, and it seems the Tak will take high power well before star images start to break down.

It does not deny the laws of physics obviously, but does seem to work very well. Obviously an FS128 side by side with a Mewlon is the best option

 

[Geoff Barnes]

6 hours ago, Stu said:

I'm struggling to find it on Skysafari

It's really odd Stu, I can't find it on Skysafari or StarWalk2, and yet it's got to be one of the best doubles out there 

I found this video which may help find it.. .  ..

https://www.google.com/url?sa=i&source=undefined&cd=&ved=0ahUKEwjY0_vR3NfgAhVNXisKHQ_PAZIQzPwBCAM&url=https%3A%2F%2Fmilky-way.kiwi%2F2018%2F03%2F03%2Fhow-to-find-the-double-star-145-canis-majoris-winter-albireo%2F&psig=AOvVaw3Km7cORJmhkezsDFvoQ_gp&ust=1551212937254011