Category Archives: Globular Clusters

Binocular session 24 July 2009

This was a very short session due to a migraine I’d acquired during the course of the day, so it was out for a quick sesh with the 8x42s. I am doing the AL Binocular deep Sky program at the moment, but I had lost the charts so decided to pick off a few objects in Cygnus instead. Luckily a couple of them are on the AL list (which – surprisingly – does not have many summer objects on it).
This was the first clear night dark enough to properly observe in ages. I poked around in Sagittarius, Bootes and Cygnus. Cygnus is my favourite area of the summer sky and is incredibly rich, being located in the Milky Way. Here, our sky is quite dark and it was better than mag 6, and the MW is very bright and detailed, with rifts and dark lanes.

The objects:
NGC 5466 – Globular Cluster in Bootes: This is easy to find, being in a direct line from the Bear’s tail (handle of the Dipper) to Arcturus, but not so easy to see in binoculars. It’s a very faint round glow.

NGC 6910 – Open Cluster in Cygnus: Small knot of stars adjacent to Sadr. Telescopically, this is one of my favourite OC’s but in binos it’s not more than a bright knot with a couple of bright stars attached.

NGC 6866 – Open Cluster in Cygnus: A small knot of stars between Sadr and Delta Cygni. A hazy, roundish patch. Hard to keep bins still at this angle and the remnants of the migraine made it impossible to look up at an angle for any length of time.

I love observing with my binoculars, they are the ultimate “grab ‘n’ go” scope, but I will be glad when I have got a servicable scope again!

Observing 30th June-1st July 2008

It was clear last night and I didn’t have to be at work today so I set up the 12 inch for an hour or two of observing under less-than-ideal conditions – it was clear enough, but as the solstice was only ten days ago, it wasn’t really dark enough for serious deep sky observing but as I am fed up with no observing and at least *something* was visible I went out anyway. As it was, it didn’t get ‘dark’ enough for observing until after midnight, when brighter portions of the Milky Way became visible.
I did, however, begin the
Astronomical League Globular Cluster Observing Program as summer is a prime time for hunting these and there are rich pickings to be had in Ophiuchus and what parts of Scorpius and Sagittarius there are accessible to those of us at these northern latitudes. I’d bought the AL’s Globular Cluster book at TSP in 2006 with the intention of doing this program.

Seeing was excellent, very steady (detail was visible on Jupiter when it rose higher) and transparency was also very good, with little haze. Shame about the sky not being quite dark, though!

Because of the fairly light sky, finding stuff was a little difficult and actually seeing it was worse, but I found things that I would never have seen with the old 8 inch.
NGC 6426 was the first GC on my list. It’s located just north of an attractive white double, 61 Ophiuchi. It was round, very faint and not resolved. I couldn’t see it at all at 44x but it was seen at 102x. 2330 UT (0030 BST).
Because of the conditions, I messed around looking at brighter stuff and then packed up at 0100 UT (0200 BST). There was, at 0010 UT (0110 BST), a bright meteor which left a green trail through Cepheus.

I got to use my new 35mm TeleVue Panoptic for the first time on my 12 inch (although it had its actual ‘first light’ on Larry Mitchell’s 36 inch Obsession at TSP last month) and my slight concerns about it being too heavy and tipping the scope were unfounded. The balance on the 12 inch, and the friction on the bearings, are so good that it stayed put when the big eyepiece was put into the focusser. The view was good right across the field to the edges, with practically no coma.

Observing, 7th-8th May 2008

A much more transparent night due probably to a breeze that had been blowing during the day and into the evening. This died down when it got dark.

Set up the scope in twilight and wondered why, when I came to align the finder and check the collimation, I couldn’t see a damned thing. The secondary holder had become misaligned but a quick adjustment soon sorted that out. The nut holding it had worked its way loose so two seconds with a spanner tightened it up – I’ll have to keep an eye on that because the last thing I want is for the secondary to work loose and crash into the main mirror, which doesn’t bare thinking about!

Date: 7th-8th May 2008:
Conditions: Clear, slight breeze (this died down after dark), cooler than previous evening, more transparent (on a scale of 1 to 5, where 1 is cloudy and 5 is excellent, this was around 4).
Scope: 12″ f5 Dobsonian.
Place: near Sandown, Isle of Wight, UK.

As the conditions were more transparent than the previous night I looked for galaxies in Ursa Major – the ‘lollipops’ M81 and M82 were superb through the 12″ ( a real ‘wow’ factor with lots of detail) and other, small, galaxies in the vicinity were easy to see: NGC 3077, NGC 2976 and, further away, NGC 2787.
Hercules was rising, so I had the obligatory look at M13 – it was a fantastic sight in the 12″ with a dense core and arms of stars radiating out from it. I didn’t do a sketch, that can wait until later in the year. While in the area, I decided to have a look at the galaxy near M13, NGC 6207. At low power (37x) both M13 and NGC 6207 are in the same field of view. NGC 6207 is a slightly elongated oval smudge, evenly bright.
It was on to NGC 6229 a globular cluster in Hercules. At 37x, this was obvious, next to a couple of bright stars. It’s small, condensed, round and bright. Some stars resolved, but only just.
After this it was 1am and time to pack in.