08/28/2023
Location: home,
Equipment:
EPs:
TV Plossl 32mm, 50 deg (84x, 2.2 exit pupil, 0.59 deg TFV)
TV Delite 18.2mm, 60 deg (148x, 1.2 exit pupil, 0.42 deg TFV)
TV Delite 15mm, 60 deg (180x, 1.0 exit pupil, 0.34 deg TFV)
TV Delite 9mm, 60 deg (300x, 0.6 exit pupil, 0.17 deg TFV)
TV Delite 7mm, 60 deg (386x, 0.5 exit pupil, 0.16 deg TFV)
TV Delite 5mm, 60 deg (540x, 0.3 exit pupil, 0.11 deg TFV)
I love darker skies and beautiful scenery of the desert and look forward my weekend trips. Home sky gotten worse over the years so I no longer observe
And that is what I did on Monday after the dinner. Rising Moon beautifully highlighted the trees around our house. The traffic noise was subdued, not that many sirens this evening. And the summer crickets set relaxing mood. We are experiencing heat wave, but the evening was pleasantly balm. This was my first session in t-shirt and shorts for this year.
CASSIOPEIA DOUBLES
MRI 31 AB (8.1, 9.0, 116.5”) – wide but nice looking pair of yellow and white stars (84x).
STF 38 (8.7, 9.0, 16.9”) – white pair (84x).
HJ 1983 (8.5, 10.1, 41”) – bright copper-colored main with dimmer steel-colored secondary, pretty pair (84x).
BU 1096 (8.8, 9.7, 12, ac35.5”, ae38.6”) – orange, white, gray (84x, 180x).
STF 43 (9.0, 9.4, 4.7”) – pale yellow pair, clean split at 148x.
STF 45 AB (6.9, 10.1, 19.2”) – lemon, navy (84x).
STT 16 (5.6, 10.5, 12.3”) – bright copper-colored main, dim grayish sidekick resolved with AV (386x).
STF 48 (7.8, 8.1, 11, ab5.5”, bc65.8”) – neat triple, close pair of bright snow-white stars with dim steel-colored speck in a distance (84x).
HJ 1922 (9.4, 13.1, 15.2”) – white main with grayish ghost of secondary resolved with AV at 386x.
STF 50 (8.0, 10.6, 22.5”) – orange, gun metal (84x).
H N 122 (5.7, 10.6, 36”) – warm white, silver (180x).
ARG 2 (7.9, 9.8, 12.7, 11.5, ab2.3”, ac16”, ad40.8”). AB – uneven white pair, snowman split (540x). C and D - faint grayish companions (386x).
H 5 82 (8.0, 8.4, 12.2, ab56.4”, ac102.2”). AB – orang pair, C – faint gray companion (84x).
STF 57 (10.5, 10.9, 6.3”) – gray pair, clean split at 180x.
STF 59 (7.2, 8.1, 12.5, ab2.3”, ac32.8”). AB – white pair, clean split at 180x, C – faint gray sidekick in a distance (300x).
ACHIRD SYSTEM
Achird (Eta Cas) is one of my all-time favorite doubles. It has a beautiful combination of colors: yellow (white in small scopes) main and rich red secondary. Achird (STF 60 AB) is a true binary with orbital period of ~480 years.
In addition to the main pair Washington Double Star Catalog lists 8 more, most likely optical, components summarized in the table below. The table was generated using Stelle Doppie website interface. They were my targets for this evening. Using powers between 84x and 180x I have managed to resolve components A, B, C, D, E, F, G, H and I, and failed J. E, H and G were white, and C, D, F and I were gray. It was a fun and challenging project, since to ID the components in the field I had to estimate magnitude, position angle and separation.
