Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Moonshane

(Finally) Observing under decent skies 23/7/2012

Recommended Posts

Although I managed a brief session under the stars on 22/7 it was hindered greatly by the encroaching stars and I eventually abandoned the session early in frustration.

The skies appeared much more transparent last night and I therefore decided to make a night of it. I am glad that I did as the skies were some of the best I have enjoyed recently. The Milky Way was just visible with direct vision in Cygnus and you could just about follow the loop all the way down to Scutum with averted vision - great! Not a patch on the beautiful vision at a dark site but very encouraging nonetheless.

Before this, as it got towards darkness but with the sky still deep blue, I decided to try a few double stars. I was interested to see if the slightly bright sky would assist with the seperation of the tighter doubles. It didn't really make a difference but I discovered during the evening that the seeing and transparency were both really excellent, and even though the sky never really grew completely dark (I observed to about 12.45am) it was a superb night.

Double Stars

As Vega is so prominent in the late evening, my first target is often the double double, Epsilon lyrae. For double star observing I mask off my 16" f4 scope to 170mm as in all but the most extreme conditions it provides tighter stars and more contrasting images generally. The f11 effective ratio also provides a small exit pupil and one effect of this is the lovely airy rings around stars which enhance the view to my eyes at least. E. lyrae was well split with both components of both sets well apart.

I then moved onto Delta cygni which is becoming a favourite of mine and easily splits at about 180x plus. The yellowish primary and tiny dot of a brick red secondary really offset each other well. Another favourite is alwats Izar, Epsilon bootis and this splits from about 150x showing a yellow primary and blue green much smaller secondary. Over to Pi aquilae and this provided such a good and well spaced clean split that I started to wonder. Could tonight be the night when I finally split Zeta Herculis??

I turned my scope onto the naked eye star and then ramped up the power. Using my 6-3mm Nagler zoom I set the zoom to 4mm (460x). I thought at this magnification I could see a hint of a split and pushing the magnification even further to 3mm (613x) provided a surprisingly stable image in periods of the best seeing. Of course the imaged was moving quite rapidly across the FOV but I managed to track this and was delighted to confirm my first ever split of this (to my eyes) difficult split. The primary was yellowish and the secondary was about a third smaller and a dimmer dirty brick red. the secondary was split from the primary but sat on the first airy disk. Backing off the power I could see it at 460x but not really with any certainty below this. It seems that very high power enabled by very good seeing is what's needed for this double star system.

Other doubles seen were Polaris, Iota Cassiopea and Almach Gamma andromedae.

With the skies getting darker now I moved onto other fainter targets and it was so good to get some good quality observing time with the big dob. Here's a summary of the items I managed to see and which include some 'old friends' and some new (to me) items.

Globular Clusters

M92 and M13 in Hercules are always a must and really never disappoint. I prefer the wider field view of these objects but again for fun ramped up the power to about 300x. Stars just continue to resolve into knots and pepper the whole field of view.

M71 in Sagitta is a much different globular being quite delicate but the wide field view provides a wonderful background of stars.

NGC 7006 and 6934 in Delphinus were both new for me and as far as I recall my first NGC globulars. 7006 was really quite faint and I could not honestly say I could resolve any stars but 6934 was really quite nice and brighter than some Messier galaxies with many stars resolved.

M56 in Lyra was again similar to M71 with many stars resolved and in the background view of the wider field.

Open Clusters

M11 Wild Duck Cluster in Scutum is a stunning cluster and well worth seeking out. One of my favourites in the whole sky - even better to me than M13.

Cr 399 The coathanger cluster always looks better to me in the finder scope than on the main scope.

Double cluster NGC 884 / 869 in Perseus is always amazing and tonight was no different.

M39 in Cygnus takes some finding. The whole area is an open cluster and through the eyepiece the whole area is just stunning. This cluster reminds me of M45 with very bright blue stars which ae very well spaced.

Galaxies

Only looked for M31/32/110 and can just fit them all (or what you can see of them anyway) in the 1.1 degree field of my 26mm Nagler. Really brilliant to see these back in the sky again. Autumn is on the way!

Nebulae

I wanted to try and see the central star of M57 the Ring Nebula but again failed to do so - I think I need a dark sky. But the central area completely filled with nebulosity and the extending 'flaps' made up for this. I even had a look at 613x and the sight of M57 virtually filling the field is amazing!

M27 the Dumbell Nebula is another must see item at this time of year. I have recently found it much easier to find from the arrow of Sagitta and going up a bit. It has recently been visible in my finder which is new I think. I managed to see the central star of this PN. The Oiii filter really helped extend this object.

NGC 6826 the Blinking Planetary is a great object in Cygnus and demonstrates how averted vision is effective. If you stare at the central star the nebulosity all but disappears; look away and it 'blinks' back into view. Highly recommended.

NGC 6888 the Crescent Nebula was just visible in Cygnus with the Oiii filter. It's much better from a dark site but this is the first time I can recall seeing it at home.

NGC 6960 6995 the Veil Nebula is always wonderful with the Oiii and 26mm Nagler. It was the best I have ever seen from home again and showed traces of fine detail and structure all over the nebula but particularly the northern end of the bridal veil.

All in all this was a really super night and I went to bed, at last having my astro hunger well and truly satisfied! I hope that others got a chance for some good observing too.

Share this post


Link to post
Share on other sites

Very nice.Now coming up to the 3rd night of clarity, must s l e e p soon.

Try NGC6905; Blue Flash planetary neb. It does. W of Sagitta.

NGC6910 is the Rocking Horse cluster in Cygnus. It does ( look like one!).

Wild duck M11 is the summer stunner, well worth finding and spending ages looking at it's shapes.

Nick.

Share this post


Link to post
Share on other sites

cheers for the tips - there's always more to see and those two sound excellent. I like clusters that look like things as they are often real crowd pleasers !

Share this post


Link to post
Share on other sites

great report moonshane, great seeing indeed....

Share this post


Link to post
Share on other sites

A very enjoyable read with a few I haven't looked at yet.

NGC 7006 is on my to do list, though the Crescent nebula isn't and with a Sb of 15.5 is probably beyond my sky capability.

Clear skies!

Share this post


Link to post
Share on other sites

Really excellent report & lots that you looked at.

Sounds to me like you are pretty experienced. Do you know where all these objects are or do you star hop?

I'm fairly new & spend ages star hopping & getting lost then have to start again. But it's fun.

Share this post


Link to post
Share on other sites

Really excellent report & lots that you looked at.

Sounds to me like you are pretty experienced. Do you know where all these objects are or do you star hop?

I'm fairly new & spend ages star hopping & getting lost then have to start again. But it's fun.

cheers all - I had a great time! @ webboid - I am experienced to some but a novice to most on this forum but very keen. I know where many objects are but some new ones have to be carefully followed by star hopping in the optical finder. I initially align with a Telrad and often the object is in the eyepiece but if not I usually star hop from the most obvious naked eye star in the optical finder. you will get the hang of it eventually

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.