Astronomy

Observing Log for

Session Details


Northallerton

54.3299, -1.44529

10m

Notes

As the moon was only a day past full, and already rising in the east when I set up the 'scope, it wasn't going to be the best night for deep sky wonders. Once I was set up I decided to take a quick trip around a few favourites just to see what they looked like before heading for some double stars and brighter targets.

Observations

M13 - The Great Hercules Globular Cluster

My first port of call was the Great Globular Cluster in Hercules. Despite the moonlight it was easy enough to pick out in the finderscope, and through the 25mm Plossl, a faint, grainy patch of light could be seen. The moon had taken away most of the detail but the dimness made it quite a pleasing sight, and averted vision brought out a certain amount of detail.

M57 - The Ring Nebula

Another target susceptible to moonlight, 57, the Ring was a lot less impressive tonight with averted vision required to make out the inner loop.

NGC 6826 - The Blinking Nebula

I will try this target again when the moon has once again disappeared, as although I found the right patch of sky, it was very difficult with such a diffusion of moonlight to definitely say I could see this nebula. It is a planetary nebula surrounding a mag 10 star which I believe I found, however when looked at directly the nebula vanishes, leaving only the star. The nebula returns only when you look away (i.e. through averted vision) and this was the bit I was struggling with. Although the star did appear to change slightly it was very difficult to confirm.

M71 - Globular Cluster in Sagitta

Located along the shaft of the constellation Sagitta, the arrow, 71 is believed to be a very loose globular cluster. In the telescope, again diffused by moonlight, it appeared to be more globular than open with a definite concentration of stars and a surrounding graininess.

Gamma Delphini - A Double Star

Double Stars are often improved by the presence of moonlight, as the diffused light improves colour contrast and allows our eyes to perceive the colours better. This was certainly the case with Gamma Delphini (the nose star of Delphinus the Dolphin) which sat last night very close to the almost full moon, yet looked spectacular. The primary star appeared golden yellow, whilst the companion secondary first seemed to be a light, lime green, but as I looked at it longer darkened to a more bluey-green. A beautiful pairing which I shall definitely be returning to in the future.

M11 - The Wild Ducks (Open Cluster)

Located in a densely populated (but awkwardly southern) area of the sky, again I thought I would take a look at this target so that I woud be prepared for a moonless night. Even under these conditions, the cluster was easy to locate and yielded a certain amount of detail. The cluster has a fairly bright star at its head, with two trails (or wings) stretching back westwards. Last night these appeared to be only fuzzy patches with only a couple of brighter stars in each wedge viewable. This will definitely be revisited once the moon has disappeared as it is supposed to be one of the most attractive of the open clusters.

Brocchi's Cluster

An asterism of stars in Vulpecula that look very like a good old metal coathanger. Too wide to fit into the field of view of the telescope, I looked at this bizarre arrangement through the finderscope (though binoculars would have been just as good). Definitely one for star parties.

Mars

Rising now at about 11pm in the east, Mars had risen above the houses (just about) by about 11:30pm when I saw it. Despite all the atmospheric disturbances, the view was very clear at low and medium magnifications, only breaking down at x200. At x100 the view was exceptional with the red-orange disc of Mars broken at the top by the star white of the large southern polar ice cap. I wasn't able to make out a great deal more detail but as it rises earlier each evening I should get better views in the coming weeks.

The Double-Double

The double-double is a star in Lyra that on inspection with a telescope resolves into four stars - a double star, each of which is itself a double. Difficult to resolve at first, it took x100 to split the double into its components. Fitting nicely into the Field of View it was a very nice sight.