The dark nights are back, if only for a couple of hours each night, and the nights are drawing in at last. Last night, 24th July, was clear although not perfect so I took my small scopes out instead of getting the 12″ out. Another reason for this was that I wanted to see what the little ones could do on the globular clusters of Ophiuchus.
Date: 24th July 2011
Conditions: Clear, 87% humidity (very dewy), 12° C
NELM: 6.0 decreasing to 5.8 later on.
Transparency: III. Clear, some haze visible. Milky Way still visible but not detailed
Equipment: 2.75″ (70mm) f/6 Vixen refractor; 4″ (102mm) Meade SCT, 8×42 binoculars; 40mm Televue Plossl, 25mm Televue Plossl, 15mm Televue Plossl.
NGC 6218 (= M12), globular cluster in Ophiuchus -Large and bright. Not resolved in little scope but granular with averted vision. The g.c. has a brighter centre and an irregular shape. 2.75″ refractor with 15mm Plossl (28x).
NGC 6254 (=M10), globular cluster in Ophiuchus – Smaller and slightly brighter than M12. Denser than M12 with a brighter denser core. Round. Unresolved. 2.75″ refractor with 15mm Plossl (28x).
NGC 6426, globular cluster in Ophiuchus – Not seen.
NGC 6366, globular cluster in Ophiuchus – Not seen.
NGC 6705 (=M11), open cluster in Scutum – Visible to the unaided eye and as a bright detached nebulous patch in the Scutum Star Cloud through the 8×42 binoculars. In the 4″ SCT it is a bright, rich, fan shaped cluster. With direct vision it just looks nebulous but with averted vision there are many stars, although there is still a nebulous background. There is a bright star on the eastern point of the ‘fan’. 4″ SCT, 25mm TV Plossl (40x).
NGC 6402 (=M14), globular cluster in Ophiuchus – Round, not resolved. Slightly brighter towards the centre. 8×42 bin.
The scopes were dewing up badly as neither have dew caps so, as it was 1am, I packed up. While I’d rather be doing some more ‘serious’ observing (for want of a better expression), just going outside and using tiny scopes and binoculars to see what can be picked up is fun and can be suprisingly productive.
The little Vixen 2.75″ is a nice little rich field scope and it’s easy to find things with. It’s also easy to use on my photo tripods. However, I feel it’s a little *too* small, but it’s fun to poke round the sky with and see what I can pick up.
The 4″ SCT is much heavier, it’s physically a lot larger and is more of a nuisance on the tripods. It’s not really designed for use on a photo tripod, but I have never had a mount for it, as I bought it second-hand a few years ago. It has to be used with a red-dot finder as the field of view is too narrow to use without one, as it’s an f/10 (1000mm focal length). I am not a fan of red-dot finders but it’s better than nothing.
I am going to want a travel scope (as I am planning a trip to the Southern Hemisphere – probably Australia again – in 2013), which necessarily needs to be small because of airline baggage restrictions but I am not yet sure that either of these will fit the bill. Maybe a good compromise will be a rich-field short-tube refractor of around 3.5 inches, such as those made by Skywatcher or Orion.
All being well, my 18″ should be ready any day now, barring any issues with the mirrors. I haven’t heard that there are any problems, so fingers crossed, it will be done soon.