Doubles From 22/10/2023

[lunator]

Excerpt of Observing report 22/10/23 covering double stars. Main report on the observing section.

I finally managed to get a couple of hours observing. The first since the 7th September.

Mr Dobbie had been out on a tarpaulin cooling down. 

Vega Collimation

At dusk I knew I needed to check everything out as the scope had been moved several times so a check of the finder alignment and collimation showed that both were well out. Fortunately the seeing was fairly good so using Vega as a star test I managed to get a good alignment. 

Double Double

First stop as only a short hop from Vega. Easily split at x150 and decided to see how low I could go. I was pleasantly surprised that all 4 components were still obvious at x60. The best view was at x100 as the splits were very clear and you got to see plenty of field stars as well.

The first new target I had was STF2508 in Draco. A wide pair of yellow stars with a sight difference in magnitude. Easily split at x50. 

The next target was STF2510A, BC in Aquila.

They are a neat pair of white stars with a slight difference in magnitude. Easily split at x50 and quite a rich field. The BC pair were not split as they are 0.3” apart.

STF2516 in Draco (again), A fairly close pair of uneven magnitude. The primary is orange and the secondary is pale blue. Part of a trapezoidal shape. The pair cold be split at x60 but the best view was at x100.

STF2538AC, AD & CD in Cygnus was the next target but I took a slightly circuitous route via ETA Cass. The first double I observed and still one of my favourites. Back to STF2538. It is a visual triple in a small scope. The CD pair are fairly close. The A component lies some distance away. All three stars appeared yellow. There are 2 other components B and E, they are both below 13th mag and we’re not observed.

My next target was STF2549 in Draco. As a moved across to it I did divert to M57. A favourite faint fuzzy of mine. It looked good at x150 with a clear doughnut appearance. STF2549 A wide triple of similar magnitude. The outer two stars appear yellow, the middle star appears white. The 3 stars curve round and point to a fainter star some distance away. The AB pair (BU655AB) were not split.

The final target was STF2552 in Sagitta. A fairly close pair with a moderate difference in magnitude. The primary is white and the secondary pale blue. The pair are set in a fairly rich field.