Friday, 25 September 2009

Aggravation, clouds and some galaxies

The forecast was clear for the night, with a run of settled weather and high pressure predicted by the BBC weather website for the next few days, so I lugged out the 12 inch for - hopefully - a good long session.
Unfortunately the session got off to a bad start when my watch broke (the pins that hold the strap in place). Then once I'd set the scope up and had left it to cool for an hour I then discovered that the collimation, for some reason, was miles out. Trying to sort out the collimation made it worse and things weren't helped when the batteries in the laser collimator died; naturally I didn't have any spares, so with the most taboo swear words I could think of I hurled the collimator across the garden in the dark. Not a good idea, as I then had to get a torch and hunt for it among the bushes, fortunately I found it after a brief search. Also not a good idea as the near neighbours across the way may well have heard some exclamations of 'for f**k's sake!', 's**t' and even worse!

I got my visual collimator out and tried to use that, but visually collimating the scope requires a second person to look through the eyepiece or twiddle the collimation knobs or one person doing it but needing the reach of a gibbon to do both at the same time. I had neither so I adjusted it as best I could and left it at that. I tried it on the Double Cluster and, fortunately, the view was reasonable, although high powers left a lot to be desired, so I decided to get on with the session. I do need some stiffer collimation springs, so I will send off for some from Bob's Knobs. These will improve the collimation no end, according to others who use the GSO/Revelation and Lightbridge scopes.

By this time I had wasted two hours sorting the bloody scope out, and therefore the observing session was shortened as a result. But I had all night...

Conditions: Chilly at 8 degrees C. Humidity was 82% so there was a fair bit of dew falling.
No wind. No Moon (waxing crescent had set earlier in evening). Limiting magnitude to the unaided eye was around 6.3 with seeing of II-III on the Antoniadi scale of seeing. Transparency, on a scale of I (excellent) to V (very poor) was III.

Instrument: 12 inch Dobsonian.

I began in Perseus, looking for the Perseus galaxy group, but failed to see it. This should not have been difficult, but the combination of hazy skies and less-than-perfect collimation probably conspired against me here.

Moving on to Pegasus, a rich galaxy hunting ground, brought some better luck. I quickly found NGC 7479. This galaxy looks, to direct vision, like it is an edge on; however averted vision shows it to be rounder and with the hint of spiral arms. The elongation seen with direct vision is the central bar of the galaxy. 101x

NGC 14, galaxy in Pegasus - small fairly bright. Oval. Elongated north-south. Slightly brighter middle. I thought I'd found NGC 7814, which is what I was looking for, but it looks nothing like it when compared to sketches and photos in books and on the net. It's definitely NGC 14. 101x

NGC 23, galaxy in Pegasus - small, very bright. Elongated north-south. There is a star superimposed on the northern end of the galaxy. 101x

I had planned an all night session but, just to round off an incredibly annoying and frustrating session, unforecast clouds built up at around 0200 BST. So much for the Mess Office and their forecasts. So I packed up at 0230, after waiting for the clouds to clear. They did eventually, but left in their wake terrible transparency so I called it a night. Not a great session, a paltry three sketches made and not much done.


As a little postscript, I went to a jewellers to get my watch fixed this afternoon, and while I was in there bought three button batteries for my laser collimator. Two small pins for my watch and three tiny batteries came to the princely sum of £13. Daylight robbery.

I have sent off to Bob's Knobs for some collimation springs and secondary knobs. I don't need new primary knobs as these are ok. Hopefully, these should enable the scope to remain aligned for longer.

1 comment:

  1. Faith, I really enjoy reading your reports. You put up with a lot to make those observations. I hope your next run is much less frustrating.



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