Observing Log 17/11/17 @ 21:30 – 18/11/17 @ 03:00
Andy, Damian & Rhys
Damian came around to my house in Lichfield for a great observing session. We both used our Orion ten-inch Dobsonian telescopes. Rhys joined us for an hour and then we continued for another 4 and a half hours.
We must really enjoy this astronomy lark! 5 and a half hours shot past as though only minutes – and this was after a long day at work and school for all of us.
Tonight’s session rates in amongst one of our best – with a number of unusual targets and the very successful use of our home-made image-intensified eyepieces – we made these years ago and had moved away from using them in favour of more “modern” equipment (video cameras) but tonight, on the Dobsonian telescopes, in a head-to-head with my Watec video camera the image-intensified eyepieces won for shear ease of use, fun and “at the eyepiece” experience – and boy were they good at helping us to observe galaxies!
I will add a post in a few minutes after this one with photographs taken through the image intensified eyepiece.
Photos below of Damian and Andy and telescopes tonight – Andy looks like he is falling asleep!
- Orion Dobsonian 10 Telescopes x2
- Vixen SG 2.1×42 Widefield Binoculars (Damian and I both made use of a discount at the International Astronomy Show this year to buy ourselves a pair of these amazing devices)
- Explore Scientific and Televue Ethos eyepieces & Televue Paracorr coma correctors on both scopes.
- Homemade image intensified eyepieces.
- Watec 120N video camera
All objects tonight found by star-hopping, with the help of Sky Safari Pro 5 on my iPad and Damian’s Sky & Telescope Pocket Sky Atlas.
Pleiades – Messier 45, Open Cluster in Taurus,17 Nov 2017, 21:30:12, Whilst Damian aligned his laser pointer to his red dot finder on Capella in Auriga, I took the opportunity to use my new Vixen SG binoculars to observe the Pleiades – with my slight short sightedness I only see a blur with the naked eye but with these binoculars I was able to see 15 stars. Wonderful! My slight short sightedness (only about 0.75 dioptres) means I am usually reluctant to wear glasses (especially outside where I would be taking them on and off to look through an eyepiece) but it is sufficient to blur detail during naked eye observing. The Vixen SG binoculars give me back the ability to see the sky in focus and their individually focusable eyepieces allow me to compensate for the slight difference between my eyes.
Messier 37, Open Cluster in Auriga,17 Nov 2017, 21:33:28, Visible with Vixen SG binoculars with averted vision – I hope that will improve as I dark adapt. 21:36:14, Update to previous comment – I have just been able to observe M37 with direct vision through Vixen binoculars. Damian took a look himself and saw a meteor go through the field of view of the binoculars – always a spectacular sight in the Vixen SG. We then used 21mm Ethos with Paracorr to observe M37. Beautiful!
Pinwheel Cluster – Messier 36, Open Cluster in Auriga,17 Nov 2017, 21:43:27, Comparing the view in my Explore Scientific 20mm vs Damian’s Ethos 21mm the view is very similar.
Starfish Cluster – Messier 38, Open Cluster in Auriga,17 Nov 2017, 21:45:25, Another nice view of an easily seen open cluster in the Orion Dobsonian telescopes.
NGC 1907, Open Cluster in Auriga,17 Nov 2017, 21:46:02, However we preferred of this cluster to that of M38 close by. Faint but we readily saw it. Not really challenging…now this would be a good one to spot in the Vixen binoculars! Not that we saw it with these binoculars tonight!
North America Nebula – NGC 7000, Bright Nebula in Cygnus,17 Nov 2017, 21:53:03, I read the other day that nothing is brighter than the naked eye view and that magnification does not increase contrast contrary to the popular view – instead it increases the number of retinal sensory cells covered by the image and hence increases visibility. Therefore, for extended large faint objects, they are easier to observe at low magnification, as long as sufficient retinal receptors are covered. Therefore, there is an optimal magnification for each object which is the best compromise between the benefits and negative effects of magnification. For many larger objects, this optimal magnification is a lot less than many of us usually think.
I decided to put this information to the test tonight by trying to observe my nemesis – NGC 7000 – I can never see it in Lichfield. I used the Vixen SG binoculars on NGC 7000 to see if they would break my run of bad luck with this object….
22:04:47…..Success with the Vixen binoculars! NGC 7000 was elusive but definitely visible with averted vision. It popped in and out of view – lasting only a moment each time but then my eye would automatically wonder towards it and it disappeared immediately. Another wow for tonight!
IC 2149, Planetary Nebula in Auriga,17 Nov 2017, 22:06:28, Well done to Damian for finding this! Drop down from Capella to Menkalinan – slightly NE from there. Clearly blurred with 8mm Ethos, but must have been a nightmare for him to find by star-hopping tonight with his lower power eyepieces. UHC filter made it slightly clearer. We did not have access to an OIII filter tonight to compare, which is supposed to work better.
NGC 7814, Spiral Galaxy in Pegasus,17 Nov 2017, 22:20:24, Found by myself and successfully observed – a great success! Wow! Very faint in these Lichfield skies. Slight darkening. I think this is the brighter of the Pegasus cluster galaxies. I have been reading about observing this Sky and Telescope. Perhaps something really for darker skies than ours but nice to have made a foray into this group.
Crab Nebula – Messier 1, Bright Nebula in Taurus,17 Nov 2017, 22:27:27, Big! Even in 17mm Ethos.
The ‘Leaping Minnow’ asterism and the ‘Cheshire Cat’ Asterism in Auriga,17 Nov 2017, 22:40:34. Damian showed me the Leaping Minnow asterism and the Cheshire Cat Asterism in Auriga, both of which are in his presentation for RAG next week after he found references to them in previous magazine articles I’d sent him. Both of these required considerable imagination on my part to see the things they are meant to look like(!) It’ll be interesting to see what other RAG members think come the November RAG meeting!
Andromeda Galaxy – Messier 31, Spiral Galaxy in Andromeda,17 Nov 2017, 23:16:39, I tried observing this galaxy with my Watec 120 video camera and seven-inch screen. This was a failure in the Dob. I had to ask Damian for his help to track the scope on Capella whilst we tried to attain focus. Too much magnification and not enough in-focus when I tried to make use a focal reducer. Stars were shooting past the screen. Not practical.
However, the image intensified eyepieces we made years ago did well. M31 was crisp and bright (but perhaps not as impressive as we’d expected considering it relative ‘brightness’…? In fairness though, Damian pointed out the dust lanes in the ‘green’ image we were viewing which was not something easily seen through our eyepieces.
‘Mirach’s ghost’ NGC 404 a Mag 10.2 elliptical galaxy showed up better in the image intensified eyepiece than in the normal eyepiece! Damian found this fairly easily in this 17mm Ethos, even with the star in the same field of view, thankfully it was just out of the range of secondary mirror’s diffraction spikes.
NGC 752 in Triangulum – this is a big open cluster found easily with whatever we used. Damian tells me he often heads to this after all the unsuccessful attempts he has had to view M33 !
Damian found M33 using the image intensified eyepiece after trying with his 21mm Ethos and heated laser pointer. Then, averted vision with 17mm Ethos allowed us to identify its enormous size and Damian claimed he could see a part-spiral structure – he did not require Lord Rosse’s enormous scope to see it! (William Parsons, 3rd Earl of Rosse (17 June 1800 – 31 October 1867) was an Anglo-Irish astronomer who had several telescopes built. His 72-inch telescope, built in 1845 and colloquially known as the “Leviathan of Parsonstown” was famously used to observe spiral structure in M51. https://en.wikipedia.org/wiki/William_Parsons,_3rd_Earl_of_Rosse)
Almach – Gamma1 Andromedae, Double Star in Andromeda,17 Nov 2017, 23:43:32, Beautiful open pairing – a main yellow/orange with a smaller sapphire blue – Nick will be proud of us looking at double stars!
NGC 2158, Open Cluster in Gemini,17 Nov 2017, 23:46:15, ‘the more difficult ‘companion’ to M35 easily seen in both scopes. I used a little higher mag than Damian, preferring 14mm Explore Scientific to his 21mm Ethos.
IC 443, Bright Nebula in Gemini,17 Nov 2017, 23:48:10, Had a look – couldn’t see – ridiculous attempt really at mag 12 – far too faint an object for these skies. I always live in hope though that we can push the boundaries!
Orion Nebula – Messier 42, Bright Nebula in Orion,17 Nov 2017, 23:49:55, First view through branches of tree. Poor view will be better later but worth recording – at 23.45.
Little Dumbbell Nebula – Messier 76, Planetary Nebula in Perseus,18 Nov 2017, 00:00:50, Damian also found this. Really does look like a miniature version of the Dumbbell nebula M27. Bright in eyepiece. Also shows up with structure in the image intensified eyepiece.
BREAK TIME – Seasonal mulled wine (Nick would not be impressed with our consumption of alcohol… perhaps less so with the warm muffin!) After Damian had warmed his toes on the kitchen radiator, we headed back out…
Little Dumbbell Nebula – Messier 76, Planetary Nebula in Perseus,18 Nov 2017, 00:35:10, Appearing larger in the 8mm Ethos, significant structure visible.
Back to the Orion Nebula – Messier 42, Bright Nebula in Orion,18 Nov 2017, 00:36:13 how sitting between an opening in the garden trees, Very long ‘wings’ in 14mm Explore Scientific 100 degree eyepiece. Unfortunately, collimation problems showed up in my scope when I used 6mm Explore Scientific – I could only see four stars. Too much of a seagull of the stars from coma. Damian could still only see four stars with 10mm Ethos in his better collimated scope, so sky conditions had part to play here. Plenty of detail though to be had including M43 brighter region around the ‘fish mouth’.
Double Cluster – NGC 869, Open Cluster in Perseus,18 Nov 2017, 01:05:46, Do you prefer the view of the Double Cluster in 17mm Ethos or 9mm Explore Scientific? Tonight, we could see that the former resulted in a view showing more of the context of the surrounding stars, the latter left a view of spectacular diamonds (the stars) on velvet (black background). Tonight, I preferred the latter but accept it is a matter of taste. Damian went to hunt for the ‘Muscle Man Cluster’ (also in the November talk), but had forgotten just how big this asterism is so couldn’t identify him – basically the majority of Stock 2 Open Cluster!
Uranus, Planet in Pisces,18 Nov 2017, 01:16:24, Too late! By time we thought of looking at this it was behind the house.
Messier 81 & Messier 82, Galaxies in Ursa Major,18 Nov 2017, 01:21:22, Excellent view with 17mm Ethos and amazing view with image intensified eyepiece, showing detail and dust lanes in the Cigar Galaxy. Incredible!
We also had a go at the RAG November ‘Christmas Night Sky Challenge’ (regurgitated Damian tells me from his 2015 talk!)….
Messier 108, Spiral Galaxy in Ursa Major,18 Nov 2017, 01:23:00, Also showed up nicely in image intensified eyepiece. In the Ethos eyepiece, it was a much fainter slash – significantly more difficult to find using normal eyepiece than with the image intensified eyepiece. Conversely, the close-by Owl Nebula M97) was much more obvious with the Ethos eyepiece and significantly fainter in the image intensified eyepiece – interesting how different objects respond differently to different modalities of observation.
Eskimo Nebula – NGC 2392, Planetary Nebula in Gemini,18 Nov 2017, 01:38:38, Suddenly expanded in size when we looked away from it (averted vision) then shrank down again when we looked directly at it (direct vision) in 17mm Ethos – this was quite a profound effect. With the 8mm Ethos, it was very fuzzy and Damian noted two shells around this planetary nebula, and some hints of detail within these shells. The 10mm Ethos showed a slightly different appearance emphasising the two layers at the expense of loss other detail. I am quite excited that I found this object first – although the truth is that I was helped by having seen it in the past with Nick using GOTO scopes, so I was aware of what it looked like and recognised it as I panned past it with a lower power finder eyepiece. This was perhaps the biggest and brightest of the ‘fuzzy stellar-like planetary nebulae’ that we observed this session.
The festive… Christmas Tree Cluster – NGC 2264, Open Cluster in Monoceros,18 Nov 2017, 01:53:41, First time seen this upright just like its name! Seeing this tonight makes me feel that Christmas is coming soon. Big object, fills a good portion of a 17mm Ethos.
Damian informed me of another addition to his November presentation build, Hubble’s Variable Nebula – NGC 2261, Bright Nebula in Monoceros,18 Nov 2017, 01:59:13, I am proud! I found this using the 17mm Ethos when Damian had more difficulty! It is usually the other way around (Damian is significantly better at star-hopping that I am) so hence my excitement. I did use his scope though, after I had tripped over his power pack and injured my shin – Damian would say, “Only you, Andrew!” (it looked pretty bad to be honest after we had finished for the night – taken a lump of skin off, ouch! – Damian).
Damian notes here: he was in the correct vicinity and just needed the more detailed SkySafari map to find the nebula (which was also his suggestion!). He’s also ‘not great’ at star hopping, but a nice low magnification/wide-field eyepiece, sky map/red head lamp and heated laser pointer all flatter his supposed ‘skills’!
We also looked at Hubble’s Variable Nebula in the image intensified eyepiece and found that it was visible there but the view was better in the Ethos eyepiece. With the 10mm Ethos, the nebula is clearly triangular. Similarly, in 17mm, the triangular shape is obvious – like a fat tailed comet.
Beehive Cluster – Messier 44, Open Cluster in Cancer, 18 Nov 2017, 02:31:50, Vixen SG binoculars made it a breeze to find this. Large ‘smudge’ in Cancer.
Messier 101, Spiral Galaxy in Ursa Major,18 Nov 2017, 02:36:26, Amazingly I think I could just see this with Vixen 2.1x binoculars by averted vision – although very faint and the view in this direction was where light pollution was maximal, so I am not 100% sure of this observation.
NGC 2903, Spiral Galaxy in Leo,18 Nov 2017, 02:37:26, Just to the SW of the
inverted questionmark that forms the head of Leo . Good view in eyepiece and image intensified eyepiece. Lesson from tonight: image intensifiers work well on galaxies, and provide an alternative to filters which do not work well on galaxies but better on nebulae.
Whirlpool Galaxy – Messier 51, Spiral Galaxy in Canes Venatici,18 Nov 2017, 02:40:54,
02:46. Damian asked me to find it then in the scope, still fitted with the image intensified eyepiece. For the first time I used this device to actually locate and then view the galaxy – just two faint cores, no ‘bridge’ visible linking them.
I saw a fantastic bright meteor coming out of Gemini with a persistent trail.
03:00. Called the session to a halt as a large bank of cloud rolled in and covered the sky.