Observing from Lichfield - Staffs. Meade 12" Lightbridge. 3-4th September

[TakMan]

Andy and I experienced one of our best ever observing sessions on Friday night 3-4/9/2010. We were joined by Andy's son - Rhys (age 7) until 2300 then continued until 0300, making this one of our longest continuous sessions and one with our best ever haul of deep sky objects… including many we have never observed before. The sky was wonderfully still and reasonably clear. The met office had forecast partial cloud until 0400 but, in the event, it turned out to be clear, reasonably warm, but with a lot of dew as the night went on.

Key lessons from the evening included:-

(i) Keep persevering – we are now observing objects that we have not been able to see in our previous 4 years. Practice really makes a difference.

(ii) Some objects are very faint and can’t be seen at first – but once observed our skills improve and it is much easier the next time.

(iii) Light pollution makes an enormous difference but it does not stop us from observing many Messier and NGC objects – don’t let it stop you!

(iv) Rhys saw 2 types of planetary nebulae, open clusters and a variety of star colours and hues – younger astronomers are greatly encouraged by spending time with more experienced observers.

(v) The Televue Paracorr tightens up stars in the eyepiece so that more detail can be seen in globular clusters and other objects.

(vi) A home built image intensified eyepiece gives a quite different perspective and can help identify objects that are otherwise obscure.

(vii) A good planetarium software programme helps with star hopping, identifying what you would expect to see when you find a particular open cluster you are looking for, and where moons of planets lie at a particular time.

Our observing tonight was done with a 12 inch Meade Lightbridge Dobsonian. We used a 31mm Nagler (82 degrees apparent FOV), 15mm Moonfish (80 degrees apparent FOV), and 7mm Nagler (82 degrees apparent FOV), and a Televue Visual Paracorr (which increases magnification by 15% and reduces coma). We also used a home made Image Intensified eyepiece based around a 30 year old Generation 1 image intensifier tube (see Rosliston Astronomy Club for instructions on how we made this eyepiece).

Milky Way

The Milky Way is not that often visible in our location but tonight we could make out the band of white between Cassiopeia and Cygnus across the sky. As the night got darker after midnight this became more pronounced and we even started to make out some aspects of dark bands within its structure. This is the first time I can say for certain that we have been able to do that from Lichfield due to local light pollution levels.

Double cluster in Perseus NGC 884 & NGC 869 Caldwell 14.

This spectacular pair of objects in Perseus glitters like jewels on a velvet bed just below Cassiopeia. We return to view them most evenings and we started our night off again with this incredible view. We were also very pleased to find that, by 2.30pm, we could identify the double cluster by naked eye 20-25% of the distance from Eta Persei to Ruchbah in Cassiopeia. Although the cluster is listed as a having an integrated magnitude of 4, the individual stars are bright points and therefore it is very easy to pick out once found – two groups of stars clearly different from the background Milky Way. Herschel described these on 1/11/1788 as “a very beautiful and brilliant cluster of stars, very rich.” – This is a very accurate description (except that there are two clusters not one) regardless in our experience of light pollution levels or telescope size – bigger telescopes simply amplify the effect and increase the wow factor!

M34 Galactic Cluster in Perseus.

We found that M34 was a gorgeous group of gems in the sky – quite obvious that it was the Messier object once found.

NGC 663, M103 and the Owl Cluster in Cassiopeia.

We found NGC 663 located at the tip of a triangle between Segin and Ruchbah and this object in Cassiopeia. An open cluster with an apparent magnitude of 7, we identified it with the help of Starry Night Pro 6. Tonight we found this planetarium software very helpful, showing us pictures of what the open clusters we were searching for looked like compared to the Milky Way background stars. Without its help we found they were sometimes difficult to identify. However, after finding a number of these clusters in close succession we developed a sense of what stars look like in a cluster and were able to easily pick them out of the background even without the planetarium software’s help. Clusters were composed of moderately tight groupings of very similar stars. The Owl cluster close to Ruchbab was more easily identified than the other two tonight and looked beautiful with two bright eyes composed from Phi Cassiopeiae and HIP 6229 and wings on both sides. Again the integrated magnitude of 6.4 did not reflect the brightness of the stars in the cluster that stood out against the background (quite different to how much we could see with galaxies).

M57 Ring Nebula in Lyra.

The rhomboid structure of Lyra below Vega is one of the most easily recognisable asterisms of the night sky this time of year close to Cygnus. Rhys enjoyed looking at the very bright Vega, which has an apparent magnitude of 0.

After several years, we are now able to quickly pick up M57 two thirds of the way from Sulafat to Sheliak in Vega. In the 31mm Nagler, we saw a small circle with a central hole – no star visible – Rhys described it as a “doughnut” – an apt description! Using the home made image intensified eyepiece the doughnut was more obvious although the central star was still not visible.

M27 Dumbell Nebula.

Having seen this for the first time recently, we returned to this tonight. Easily found by star hopping from Albireo in the neck of the swan (Cygnus), we jumped to 13 Vulpeculae at the end of the triangle which forms Vulpecula, and identified Eta Sagittae at the end of Sagitta. M27 was easily found _ of the way up from Eta Sagittae to 13 Vulpeculae. The hourglass figure was obvious and the nebulae surprisingly bright and large.

Andromedia Galaxy M31 and Satellite Galaxies M32 and M110.

It has taken us quite along time to work out how to star hop to M31 but we have managed to get there – Mirach in Andromedia on an “arm” off the Great Square of Pegasus is quite bright and easily identifiable. Mu Andromediae above it is more difficult to recognise on another “arm” (I have put the words “arms” here in italics as they are not arms on the figure on Andromedia), unless you realise you are looking for a much fainter star. Once you realise that, it is easy to pick up and another “star” approximately the same distance Northeast of Mu Andromedia as Mu Andromedia is Northeast of Mirach (i.e. follow the line the same distance again). The core of M31 is very bright and obvious once found, and with averted vision tonight we could follow the galaxy out to 2/3 of the field of view of the 31mm Nagler – this took a lot of effort as the galaxy was very faint outside of the core. We found that we could easily identify one of the satellite galaxies – M32 – a condensed group of stars looking very much like a globular cluster – reasonably bright. However, it took us a long time to identify M110. This is the first time we have managed to observe M110. We eventually found it located just over the same distance from the M31 core as M32 - the image intensifier helped with our initial identification of M110, and we needed to use averted vision and tapping of the telescope tube to pick it up with certainty. If M32 is thought of as being at 12 o’clock relative to the M31 core then M110 was located at 8 o’clock on the opposite side of the core. It was very faint without a core, and initially we couldn’t see it at all. Once seen, though, it became easier to observe, the more often we looked at it. All 3 galaxies (M31, M110 and M32) all just fitted into the FOV of the 31mm Nagler. Initially, it was a horrendously faint grey blotch only visible by averted vision but later we could make it out (just) by direct vision….next time should be much easier! Interestingly, although the image intensifier helped pick up the faint satellite galaxy, it did not lead to a significant increase in the size of the core of M31. Once we were able to see M110, we also found that it was easier for us to observe other faint objects – so it is definitely pursuing our observing attempts of faint objects – to train ourselves in the observing skills necessary to pick up such DSO’s.

Globular Cluster M15 in Pegasus.

We found that M15 is a pretty, bright, small condensed globular cluster in Pegasus when we looked at it through the 31mm Nagler. To find it we star hopped from Enif in Pegasus and using Equuleus as a guide – about 20% up from Enif to 1 Pegasi and move slightly to West towards Equuleus. There was some sense of structure seen with the 15mm Moonfish and some outer stars were resolved with the 7mm Nagler. The core was really dense and the whole effect was quite awesome!

Our view of M15 can be compared to Messier’s in 1764 who described it as “nebula without a star; it is round and brilliant in the centre”, and Maraldi on 3/6/1764 as “a nebulous star, fairly bright and composed of many stars”.

M2 Globular Cluster in Aquarius.

We dropped down from M15 to M2, another very condensed globular in Aquarius. We found this cluster once we worked out which star was Sadal Suud! This cluster did not hold magnification as well as M15, becoming an amorphous blob @ 213x with the 7mm Nagler.

M13 & M92 Globular Clusters in Hercules.

We had to stop by M13 on the way past to admire this incredible globular cluster – but did not spend too much time as we wished to take a look at M92 which we had not observed before. M92 is famous for being the overlooked globular in Hercules. This was also a very condensed globular and very bright, found a little further away from the Hercules rhomboid keystone asterism that we expected from the star maps or planetarium software – we have found that it is often an issue about how you interpret the maps to work out exactly where to look in the sky to find objects. Once we added in the Paracorr (adding 15% to the magnification and tightening up the star images), we were able to start to resolve some outer stars. With the image intensifier eyepiece, the core of M92 was far less bright but more individual stars were resolved in the cluster – not at all what we had expected and demonstrating how different a perspective the image intensifier gives to traditional eyepieces. This really is an indispensible addition to our eyepiece boxes and surprisingly easy to make – really does not require a great deal of skill (see Rosliston Astronomy Club on how to make one for yourself). Our preferred view was the 30mm/15mm plus Paracorr – showing tight round stars without coma and bright core. The outer regions of the cluster stretched 4-5 core diameters away from the core. Stars could be resolved even with the 31mm, and persistent observing over 20 minutes dramatically improved the amount that we could see – more stars could be resolved and more of the outer regions of the cluster became visible with more structure. We had some debate between us about whether the cluster was elongated in one direction. Looking at “Messier’s nebulae and star clusters”, Messier did not describe elongation, nor did Trouvelot show any in his drawing at Harvard College Observatory in 1874, so I guess that that aspect of our observation was spurious! However, what do other folks think? – Please let me know!

Cygnus

In Cygnus we concentrated upon observing objects around Albireo and Sadir. The swan asterism stands out in the sky making these stars easy to identify.

Another object we saw for the first time tonight with the globular cluster M56 in Lyra. We found it half way between Sulafat in Lyra and Albireo in Cygnus. This was faint even in the image intensifier eyepiece. Starry Night Pro lists its magnitude as 8.5 and this demonstrated just how faint such objects (even if globular clusters) are at this magnitude. The image intensifier confirmed that this was a globular cluster by bringing out more resolved stars where adding magnification did not help identify the nature of the object.

M39 Galactic Cluster and M29 Open Cluster in Cygnus

This is a galactic cluster located in a very dense part of the Milky Way between Deneb in Cygnus and Lacerta. We really needed to use Starry Night Pro here to confirm that we had found this cluster by comparing our view in the eyepiece and what was shown on the software.

We found the M29 Open Cluster next to Sadr in Cygnus was a disappointment in the eyepiece as it was hardly different to the dense background Milky Way at this location. It stood out as a group of similar stars, allowing us to find it and then to confirm it by comparing it to the image in Starry Night Pro 6.

Jupiter and Uranus.

Jupiter was spectacular tonight in the steady atmosphere. We could observe five separate belts (even without the SEB being present), and the moons Europa, Io and Callisto in line at 0050, and later the end of the transit of Ganymede at 0130. We identified Uranus as a very small blue disc and confirmed it from the field stars – the small blue disc is not much bigger than many star images in the eyepiece so the confirmation was necessary. We felt that Uranus looked better at lower magnification with the 30mm or 15mm (where it was subtly icy blue). At 213x, it lost its colour and was not as pleasing to view.

M71 Globular Cluster in Sagitta.

M71 globular cluster was very faint. Again the image intensifier reduced the intensity of the core, and showed several stars more brightly than without the image intensifier.

Tonight’s failures

Despite extensive efforts, we weren’t able to identify either the Triangulum galaxy M33 nor M74 Spiral Galaxy in Pisces - may be next time!

Thanks for reading and clear skies to you all.....

Damian and Andy

[Doc]

Wow that must have took some time to write, I thought I wrote long observing reports

Loads of objects seen and I bet the views were fantastic. I'm in the same boat as you, I get a little coma in my FOV as well.

I would love the Paracorr but a little out of my price range, and dread the thought of buying and finding out it don't reach focus with my eyepieces. I tried the SW Coma corrector and that never reached focus.

Are you going to Kelling by any chance?

[Mouse on the Moon]

Great Report!

Thanks.

[Nick P]

Great report Damian, a thoroughly enjoyable read - thanks for taking the time to write it.

I particularly empathise with your point (iii) about not letting light pollution put anyone off observing.

Best

Nick

[Talitha]

Wonderful report Damian, and thanks for the tour!

[TakMan]

Thanks for the feedback everyone - Andy has to take most of the credit this time for the write-up....

I have to say (even though at heart I'm a wannabe imager), it was great to be out under the stars again - with a good friend, plenty of banter, very little set-up time and no blumming cables!

Sorry Mick, but I'm not intending on a trip to Kelling. I'd have thought that the Paracorr would be fine with your eyepieces.... have you emailed TeleVue for advise...? It really does work as described, but I suppose "being worth the outlay" is a different matter altogether.... Andy and I did a report on it's use (with the 31mm Nagler an 30mm Moonfish), in a previous post of mine if you're interested....

Thanks again...

Damian

[John]

What a great report !

It's postings like this that provide motivation to others to get out there and see this wonderful stuff for themselves

Thanks for taking the trouble to prepare and post this

[russ]

Struth, that's that's a big report but a superb one. Really enjoyed the read and what a awesome time you had.