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Observing log 25/5/14 Andy and Damian, Lichfield. 'David Lukehurst' 222mm 4 Truss-Dobsonian Telescope with single spend MoonLite focuser. Takahashi TS102s triplet APO refractor on a Nova Hitch Alt/Az mount, latter on its first 'proper' night out after delivery from USA. The hand built CNC machined mount has slow-motion controls, integrated 8192 step encoders and a Sky Commander XP4 DSC (Digital Setting Circles) for Push-To operation. Tonight we were able to use this to aid pointing Andy's scope to various objects and compare the view in the two scopes - aided by using heated green lasers on both scopes. Damian also has an Astro Nevices NEXUS WiFi unit to connect the mount up to an iPad (instead of the Sky Commander unit), running (in our case), Sky Safari Pro 4, although tonight I used that for note taking, with Damian opting for the more traditional approach of Sky Commander in conjunction with his own modified (white stars on black); Michael Vlasov's 'Deep Sky Atlas'. This has been laminated and modified further with annotated/bright 'colour coded' stickers (Sasco Wall Planner ones!) to aid picking up on other targets when on a particular page. To keep trailing cables down to a minimum Damian has added a RavPower 15000mAh lithium polymer battery with a 12V output - £40 from Amazon. This is velcro attached underneath the Nova's built in 'Sky Commander tray'. With a 12V source (rather than a small 9V battery), it not only allows the 'SC' unit to run in hi-encoder mode so that encoder tics are not skipped if the scope/mount is inadvertently moved quickly but also powers a small LCD heater element to keep it functioning when the temperature drops. The Li-poly battery will also power the NEXUS device and re-charge an iPad/tablet as well if needed. He still uses though a tradition 12V 'power tank' to run his dew controller and straps. The one fitted to the scope was not required this evening, but the laser pointer/finder we find does require heat to keep it functioning effectively, even on milder nights… Whilst still setting up the Dob, Damian aligned his already levelled mount on two stars - firstly Polaris and then Arcturus, so that the Sky Commander knew where it was pointing. As he does not yet have an illuminated reticule eyepiece he used a combination of the Tak 7 x 50mm finder, 6mm Ethos and laser to get a fairly accurate alignment. As far as I am aware he never re-did the alignment all night (or re-synced on another star), yet every target we viewed was nearly centred throughout four hours of observing - a testament to the device and the orthogonality of the Nova Hitch plus the stability of the Berlebach Planet tripod that it all sits upon. Once done, he viewed a bright Mars in the 6mm Ethos (136x), just discerning two bright regions. He could have done with upping the magnification but by then I had the Dob set-up and was ready to go... After last months presentation where we discussed massive galaxies and despite the lateness of the 'season', Damian directed me to M87 in the Virgo Supercluster (appearing as a large amorphous blob), then onto NGC4435 and NGC4438, better known as 'The Eyes' in Markarian's Chain. Brightness mag 10.8 for 4435. From here I star hopped myself to M84 and M86 and M88 and a couple of other NGCs but the other galaxies more difficult to discern as they are now dropping down into the West and the murk of city lights. Even at this late hour (now past 11, the sky was not really dark, but in the UK we have to take observing opportunities as and when we can get them - and clear over a Bank Holiday weekend is something of a rarity! Damian now directed me to the 'Silver Needle Galaxy', NGC4244 in Canis Venatici (The Hunting Dogs). Just about visible in Takahashi TS102 by averted vision - would we have been comfortable confirming such an 'observation' if we didn't have the knowledge that the mount/DSCs were doing such a good job? In the DL Dob, it was visible by direct vision but still exceedingly faint. The Dob has four times light gathering of Tak, and roughly twice the focal length, meaning my 14mm ES 100 degree eyepiece was delivering 1600/14=115x magnification compared to Damian's 81x 1with his 10mm Ethos eyepiece. He opted to change to his 13mm Ethos at this point. Cor Caroli (THe Heart of Charles) was splendid viewed in the Tak showing vibrant colours. NGC 4485 and 4490 can be located next to the star Chara (the other bright star that makes up Canis Venatici), to the West of Cor Caroli. In the Tak, both galaxies were visible together as bright single galaxy, although just resolvable as two rather than one like a close double star. Looking much bigger and very bright in the DL scope, I remained convinced that the two cores could be discerned and that the proximity of two galaxies explained the apparent brightness, especially as they are listed as mag 11.89 on Sky a Safari 4. I agree with Damian, he did very well to 'find' such a dim galaxy pair in the four inch scope even with the help of DSCs! M94 in a Canes Venatici - bright in the Tak and VERY bright in the DL. Quoting Damian "the Tak on Nova Hitch makes a brilliant (if somewhat expensive) finder scope for the DL!" His shiny new Nova Hitch is really great. Worth all the wait. It looks amazing as well, like Damian has taken something out of the Millenium Falcon from Star Wars and brought it back down to Earth to help him look back at the stars!! I am very excited! I successfully star hoped to the galaxy M108 and the adjacent Owl Nebula M97 in Ursa Major, showing the two darker 'eyes' set within a bright circle - hence the name 'owl'. Then, in an about turn, Damian used his scope to confirm my finding, his laser pointing right at the target once the 'units' on the Sky Commander and counted down to it. He then took me to M106. This galaxy, also in Ursa Major, was significantly brighter and wider than M108, although about the same length. It's core was much brighter and hence a lot easier to see in the Tak than M108 had been. The Sky Commander helped us identify M101 also. Although this has very low surface brightness (not helped by a dark grey rather than black sky), my biggest problem is the star fields around it - not much difference in magnitude. The Tak did well to show the galaxy even with only four inches although more detail in the DL as we expected. I had a go at drawing M101. Just to East of Cor Caroli in a Canes Venatici, Damian found NGC 5005/Caldwell 29 and NGC 5003 which Damian felt was much fainter in his scope. Viewing through the refractor, and 13mm Ethos both were visible within in same field of view - separated by a faint star. In the DL Dob with it's longer focal length, I had to cross about two fields to see both. Again, easier to see in DL and although there was a brightness difference it wasn't so obvious as both pretty 'bright' in DL. In the Tak, I initially couldn't see the the fainter one until Damian helped me out. I'm glad he persisted as I was so happy when I saw it at last. Damian dropped straight down to the globular cluster M3 half way between Cor Caroli and Arcturus in Bootes. Compared to NGC 5003, this burnt our eyes out it was so bright! In the DL stars could be resolved well into the core. Wow! Typed M53 (a globular cluster at bottom Com Berenices) into the Sky Comander and again it appeared in the centre of the 13mm Ethos. Bigger and brighter in DL with stars resolved unlike the Tak, although it is worth bearing in mind we had both been using similar focal length eyepieces, so Damian's scope, at half the focal length of the Dob, doing it's best to 'compete' against the increased light collecting area of DL using a lower magnification/brightness and its better inherent contrast. Close by this is NGC 5053. Another faint globular cluster, but even with the Sky a Commander/laser pointer directing the DL, neither of us could see it. Shame! Just below Arcturus we observed in both scopes 'Picot 1', Napolean's Hat. A little asterism of seven bright stars that really does look like the hat he wore! It does not even appear on the search function in SkySafari 4 - something nice missing from their database. Damian tried looking for NGC 5466, another faint globular cluster, to the Northwest of Picot 1. It sits at a similar altitude to Izar and is between that star and M3....... but without success in either scope this time. At a recorded magnitude of 9.1, it should have been easy to spot...? We will have to return. NGC 5557 is a faint galaxy (mag 11.10) just off Seginus in Bootes. This time we were able to obverse the galaxy. Round in shape. Obvious in DL but boy was it faint in the Tak, needing patience and adverted vision. That make it even more puzzling why we didn't locate the previous target. Certainly the Sky Commander/Nova Hitch was aligned otherwise we never could have confirmed 5557's location. Damian's new observing chair, an ironing chair by Leifheit from Amazon did a great job - for less than £40 you can't go wrong! It collapses into easily portable and storable dimensions making it easy to transport in the car, it provided adjustable height and was quite stable. I have got to get one....actually I have already ordered it! Damian headed off to try and resolve the triple star system - Mu Boötis, better known perhaps as 'Alkalurops' in Bootes using his 6mm Ethos (136x) eyepiece on his scope. He found a beautiful close double with a blue and a white star. It was now 01:36 and there was an unusual site for our area - I could see all the stars of Ursa Minor by naked eye without difficulty. Demonstrating that the sky was now quite dark and more importantly transparent. M10 and M12 in Ophiuchus showed resolved stars in these bright globulars into the core. M5 in Serpens turned out, when we looked at it, to be a more compact globular cluster with a particularly bright core, and again stars could still be resolved well in towards the core structure. NGC 6058 in Hercules in a faint planetary nebula at magnitude 13.0 - even with the Sky Commander this was difficult to find and confirm! Required the additional help of Stellarium on my laptop to double check the starfield, but when we eventually found it with the 9mm Explore Scientific eyepiece in the DL it was obviously non-stellar - BUT it did require these high magnifications to show it as non-stellar object. The 9mm on the DL gives a magnification of 1600/9=155.5x. Damian could only see the faint star by it, at mag 13, the planetary nebula was beyond the limit of the refractor. We went looking for NGC 6207, a faint slash of a galaxy we saw in Hercules a week or so ago. This should have been easy given the sky conditions I described above. However it was only just visible and only then with Sky Commander showing the us the way and using the DL scope with 9mm eyepiece. No joy in the refractor. Looking at Ursa Minor we could see why. It was now 02:35 and high moisture levels in the sky had led to the obscuring of most of the stars of Ursa Minor. This time of year, in any case, the sky does not ever truly go dark. Backwards 5 asterism just off the keystone 'Star 23' in Damian's little asterism book he found online, looked so different in the two scopes as one is reflected compared to the other! In spite of this, the view of M13 with 9mm through the DL was simply stunning. A cross shape with masses of stars I just had to have a go at drawing it! Meanwhile, Damian found 'Markov 1', the mini-teapot asterism north-northwest of the star Xi Hercules, itself southeast of the keystone asterism. This did indeed looked like a mini version of the famous teapot in Sagittarius. We viewed it through the Tak. With a brightening sky we finished with old (relatively bright) friends: Firstly, M57, The Ring Nebula in Lyra - in the DL with 9mm this was very bright and large. clearly the ring itself was wavy around its circumference rather than an exact circle and the centre of the ring, although lighter than the circumference, was not as dark as the surrounding sky, reflecting the fact that this area is also filled with gas expelled from the central star. I could not observe the central star itself, not surprisingly considering it's extremely faint magnitude. The Tak offered the classic 'wide-field' view showing the polo mint residing in a fantastic starfield. Dumbbell Nebula, M27 - big in the DL! using the 9mm. Alberio -yellow primary, blue secondary at the head of 'The Swan', we've been out so late we're viewing late summer targets now! More colour in the Dob but not as sharp as the Tak, both well collimated tonight, although looking at double stars with 9mm shows you the fact that DL not as well collimated as the TSA. We called it a day at 03:02. Dawn starting to really lighten the sky in the east, stars and contrast disappearing and the Blackbirds starting to sing. Surprisingly two things we did not observe together we're Mars early in evening as behind a tree for me with the DL - plus we were more interested in galaxies at the time, and Saturn as it never got high enough to clear a bush at the side of Damian's garden! Forgot to re-visit Comet PanSTARRS too! A good half hours worth packing away - it's amazing just how much gear you accumulate over the years(!), then the customary whiskey and cheese and tomato on toast to finish (breakfast this time)! Thanks for reading, clear skies... Andy and Damian