Monday, 24 November 2014

It was observing Jim, and just as we know it!

Good evening!
To kick off this posting, worthy of mention at this early stage is that last night was the first proper frosty night of this Autumn so far.  For some time now, I have been trying to arrange an observing session with my friend Jim but have always been beaten back by weather and availability.  However, on Saturday, the forecast for Sunday evening was looking very good.  I fired off an email to Jim, and within an hour, he had come back to me.  We were all systems go!
Our observing site was to be Jims back garden.  He lives in a rural location near to the border between England and Wales, and has access to some fantastic dark skies.  In the stages of planning a joint observing session together, we decided ideally that we would take into account the phase of the moon, but in truth, I think that anything would suffice other than near full moon conditions.  As it happened though, we struck lucky as we were only a day or so past new moon.
Part of the idea of a joint observing session was also a chance to compare several scopes at the same time.  I took my 150mm reflector, and Jim had his 120mm refractor and finally, the latest to his collection, the 14.5” JLT Dobsonian.  There was sufficient room to set up all 3 scopes with plenty of room around them.  A wise idea, and a good technique of disaster aversion if you ask me.  The last thing you would want would be to hear the clatter of metal and glass come crashing down as one or both of us stumbled into any of the apparatus.
So, I turned up at Jims house, and was about to be shown around to the back yard by his wife when this red LED head torch come wandering down the side of the driveway.  Jim was already set up with his refractor and on his way.  I described the session as a joint observing session with Jim.  In truth, I didn’t see Jim as such most of the night.  I spent my time talking to the red head torch, and it replied.  I assume it was on Jims head and no-one else’s.
I had tried to compile a mental list of targets for the evening, but having not observed from the site before, I wasn’t completely sure what restrictions there were other than some trees to the North East.  So, I decided to wing it.
To observations.  We first looked at some popular and easier objects with the intention of comparing the scopes.  This was to be the first time that I have looked through a larger aperture reflector than mine, and it was good to be able to do it side by side, on the same object, on the same night.  We picked out the Pleides (M45) as the first target.  It was rising steadily from the horizon, and our vantage point at around 6.15pm was really quite good.  In comparison, the view between the refractor and my reflector was similar I would say.  Similar in contrast and the ability to resolve the stars making the target up.  When viewed through the dob, we had hoped to make out some nebulosity, but this wasn’t to be.  Even with the 14.5” mirror.  This might have been due to it’s comparatively low position at the time of viewing.  Nevertheless, there was an abundance of stars in the view finder, many of which I couldn’t pick out with the 150mm.
From there, we went onto the Ring Nebula (M57) in Lyra.  At magnitude 8.8, it’s well within the ability of both scopes, and a target I have visited often.  We both found the target quite quickly, and using averted vision I was just able to begin to make out the darker central areas to the nebula that gives it the characteristic ring shape.  Through the dob, we were able to view at a higher magnification.  The target wasn’t particularly filling the eyepiece, but the greater light gathering power of the dob meant that the ring was much more apparent.  I was also able to resolve the single star to the edge of the nebula, often caught in photos.  However, I couldn’t see anything that could have been the star in the centre of the ring.
Whilst in the area of sky directly above us, we decided to move onto the Dumbbell Nebula (M27).  This is an object that I have viewed from quite a few locations, and at different phases of the moon.  These were undoubtedly the best conditions over the last year that I viewed it in.  Through the 150mm I could see the nebula quite clearly, but regardless of the magnifications and time at the EP, I couldn’t be sure of verifying any structure.  However, Jim had found the target, and at a greater magnification, we could both make out distinctive ‘bites’ take out of the circular shape of the nebula which gives it the ‘Dumbbell’ name.  Another big tick to the dob!
Whilst searching in the sky charts for a next worthy target, I noticed how damp things were getting.  Even more so when looking through the Telrad.  Sadly, my home made Telrad dew shield wasn’t quite doing its job.  I can confirm that as good a bit of kit as my Telrad is, it possesses a mysterious dew attractant field around it.  It might need a bit of a re-design on that front.
So, to the next target in the constellation of Sagitta.  I last visited M71 back in July in Summer conditions.  It was the first globular cluster of the evening, and at magnitude 6.1 it stood out very well against the background of the autumnal sky through my 150mm reflector.  Unfortunately, we didn’t look through neither of the other scopes at this cluster.  Jim was trying to locate Uranus, drink hot chocolate and eat cookies at the time.  I can fully understand the effort this was taking and was quite happy to show the target in my reflector before then moving on to the next object.
M33, or Triangulum galaxy is a magnitude 5.7 spiral galaxy and is reasonably large.  The interesting thing with comparing the view of this galaxy in each scope, was that the extra aperture of the larger dob didn’t seem to bring out much more detail.  Although later at a larger magnification through the dob Jim may have started to make out some of the darker areas between some of the spiral arms of the galaxy.
A short hop to Andromeda, and another batch of favourites for many.  Conditions were cooling down rapidly, and frost was forming readily on most surfaces around us, but the seeing conditions were excellent.  This give rise to the first of two ‘firsts’ for me.  I’d never appreciated the visibility of Andromeda to the naked eye.  Generally, when I have viewed it in the past, it’s been lower on the horizon and certainly to the naked eye, washed out.  However the conditions on the clear moonless night meant that we could see the galaxy quite clearly.  Although, using the Telrad to get it lined up in the scope was almost impossible because of the afore mentioned dew on the glass.  I persevered.  I got there in the end.  The view, as was expected, filled the EP of the 150mm and I could easily make out the nearby M110.  However, I was always aware of the existence of M32 in the locality but couldn’t identify it in the 150mm.  Through the 14.5” dob though, it was resolved with ease.  Going back to the 150mm with the image of from the dob in my mind, I was then also able to positively id the location of M32 in amongst the rest of Andromeda.  This positive id meant that I could confirm the sighting and not assume that a small lighter smudge was the target as I have had to do before.  Another good tick for the dob!
It was time to move on and when asked by Jim for a suggestion to another target, I happened to be looking at the page on the sky atlas that showed an object NGC 7662.  It’s an object that I hadn’t come across before, and was labelled as the Blue Snowball Nebula in the constellation of Andromeda.  I certainly knew I hadn’t observed this target before, and Jim couldn’t recollect it.  Given that, we had no visual expectations of what the target looked like, how big it was, or an idea of it’s magnitude, we decided to go for it anyway.  Locating using the Telrad should have been very easy.  I spent quite a few minutes tracking down the area in the sky where it should have been observable.  I was using the 25mm EP.  However, Jim was also scanning the same area of sky unaided at first.  It might have been at this point his red dot finder sprung into life.  Nevertheless, he claimed the success of the first observation.  Because of its altitude in the sky (being quite close to zenith), it was time to break out the step ladder!  Up until now, it was necessary for me to stand tip toes on a small step.  Jim being taller than me was able to observe most targets comfortably.  But, even Jim had to resort to the stepladder for this one.  My first view through the dobs viewfinder was fantastic.  A brilliant blue circular nebula pitched against a very black background surrounded by several small stars.  It's magnitude is 8.6 and the object itself is quite small.  This was the reason why I had not picked it up initially.  I had observed the object, but only at low magnification.  I changed to my 8mm EP and then picked it up straight away.  It’s a fantastic and beautiful object and certainly for me, the target of the night.  I would love to show this one off to someone else in the future.
The evening was progressing, and as always, when you’re enjoying yourself, time moves quickly.  It was almost time for me to leave, but we chose to squeeze in a couple more targets for the night.  We moved our scopes around to the constellation of Auriga and quickly picked out M36 and M38.  Both open clusters, with M38 being the slightly dimmer of the two at magnitude 7.4.  Both these clusters were well populated, but with not much time left, we had no time to properly compare the views through the various scopes.  However, looking at Auriga in the sky atlas, it certainly is an area of the sky that I want to spend an evening on.
We started to pack up by around 9.30pm rather begrudgingly.  The conditions remained stable all evening, and there didn’t seem to be any deterioration in seeing.  The forecast for the rest of the evening was for fog to come in late at night and in the early hours which just made me want to stay out to eek out the last of the good conditions, but it was time to go home.
So, to summarise, aperture is important, as is focal length.  A larger scope in some ways does help to see more.  Comparison showed though that it doesn’t always work like that, but more often than not, aperture fever and telescope envy happens for good reason!
Our list of targets for the night give a mix of the popular and first timers.  It’s given me some more ideas of areas to observe and work on in the future, but also reaffirms my thoughts on the worth of revisiting traditional favourites.  There’s always something new to see.
Until next time,

Clear skies.

1 comment:

  1. Yes, it was a good observing session. I'm looking forward to the next one. Hopefully M42 will be up...and after that...Jupiter :-)

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