Autumn Clusters

21 September 2019, 21:00 – 22:30 BST

Conditions: much the same as Thursday – very mild for time of year, bands of clouds moving slowly from the south.

Started off with a quick eyepiece comparison (viewing the Double Cluster): now I’ve looked through the Ethos a number of times, I can really see the flaws in the Orion Deepview 28mm. It has approximately the same size eye-lens, but that’s where the similarities end. The Deepview’s coatings are inferior (that’s obvious in daylight) and the sharpness falls off very quickly from the centre. I’ve also noticed before that when looking at a bright object like the moon in the Deepview, the shadow of the secondary mirror is visible. To be fair, the Deepview is a perfectly acceptable starter eyepiece (and easier to look through than ones I’ve used in the past), but I wonder if it’s really the best choice to bundle with an f/4.7 scope (especially one marketed in the "Plus" range). I doubt I’ll be using it again other than for demonstrating to others the difference between a budget and a premium eyepiece.

All subsequent observations with the Ethos 13mm.

NGC 6940, open cluster, Vulpecula
Rich, elongated cluster. On this occasion (and in this eyepiece) it looked a little like a swan in flight (which would be more apt if it were in Cygnus).

NGC 7160, open cluster, Cepheus
Attractive little cluster with five bright stars arranged in two groupings. One to revisit at 240x on a better night.

While sweeping the area around this cluster I stumbled upon Xi Cephei (Kurhah) – a really neat pairing of two bright stars. The colours were subtle, but the primary appeared to be white or very pale yellow, with a pale blue secondary roughly 10 arcseconds to the west.

NGC 7235, open cluster, Cepheus
Misty little spray of stars, 2 or 3 moderately bright members.

M34, open cluster, Perseus
Array of bright stars surrounded by a loose hexagon of stars, like a large spider sitting in a web. 2 close stars of equal brightness form the “eyes” of the spider. Looks good in the Ethos.

Nature note
Two large frogs (one of which left the pond to go roaming) and sixteen froglets.