Observations - 24th October 2020

Good evening, all my Irish mates.

We have had so many cloudy overcast skies over Dublin over the last 2 weeks after sunset.
But on Saturday 24th October 2020 the skies cleared during the late afternoon.
So as soon as I got home, I set up my William Optics 158 mm F/7 apochromatic refractor in my back garden to seek out 2 doubles, 1 triple and 1 quadruple star in Cassiopeia.
As usual all these figures can be found on www.stelledoppie.it

There was some wind at times as the temperatures went down to 4 degrees Celsius and the seeing was generally quite poor at times.

However, as the big "W" is high above yours truly, that didn't matter much.

1. ES 1865 is an optical double whose magnitudes are: A = 9.8. B = 11.0. Sep = 23.9". PA = 122 degrees. I could see the faint secondary at 112X with plenty of space in between the 2 stars. ES stands for Thomas Espin. Both stars are white.

2. STF 10 was my only new Struve of the night. A & B are a true binary. But C is optical. Magnitudes: A = 8. B = 8.6. C = 11.1. Sep's = 17.5" & 55.4" from A. PA's = 176 & 103 degrees. These 3 white stars are very attractive at low power. Even the tiny C component was visible at 40X. That clearly was because of the wide separation. The system looked very good at 112X too. I thought it looked rather similar to 2 eyes and a long nosed individual. Lol!

3. ES 1934 is an optical double. Magnitudes: A = 9.2. B = 10.8. Sep = 7.3". PA = 70 degrees. The secondary proved to be rather elusive to see. At 112X and 140X I was only getting glimpses using averted vision. Thankfully 167X did the business.

4. ES 115 is an optical quadruple system. Magnitudes: A = 8.1. B = 11.1. C = 10.8. D = 12.1. Sep's = 9.5", 23.2" & 44.7". There are other quadruples which are far more attractive than this fellow. The companions are seriously faint. So much so I required 280X to see the tiny speck of the D component. At 167X I could see the first 3 luminaries.

5. Before I set out to observe Mars I observed STF 93 (Polaris). Magnitudes: A = 2. B = 9.1. Sep = 18.4". PA = 236 degrees. I had no hassle seeing the secondary at 40X. But I did admire its position directly up from the primary. Nice!

6. Before I get to Mars itself, I should point out that there was a true binary quite close to the Red Planet. 77 Piscium has magnitudes: A = 6.4. B = 7.3. Sep = 32.7". PA = 84 degrees. Effortlessly split at 11X with my William Optics 70 mm small apo. But even at 40X, I could easily see the double and the planet in the same 2 degrees FOV in the main scope.

7. And so to the Red Planet itself. Mars' magnitude was -2.4. Its distance was 65,823,063 kms from Earth. Its angular diameter was 21.2". The CM (central meridian) was 41 degrees.
At 112X I could see large grey areas across its centre.
At 140X the South Polar Cap came into view.
But the planet very much came alive at 225X with my 5 mm Nagler and that is despite the difficulties I was having with the seeing conditions for most of the time. I have since "discovered" that the large grey areas were Mare Erythraeum and Sinus Meridiani from www.skyandtelescope.com . Further north was Mare Acidalium which formed as a dark collar very close to the top of Mars. And right at the very top was the North Polar Hood. I have never observed the NPH before and it is relatively easy to see by anyone with a good scope. It all means that I have successfully observed water ice clouds at Mars' north pole for the very first time in my life!! The North Polar Cap is beyond our reach right now. But I will keep this very special memory for the rest of my days. To God be the Glory! What a fascinating Solar System we live in! Amateur astronomers on www.cloudynights.com have helped me out in regards to Mare Acidalium and the North Polar Hood.

8. And so, finally, a carbon star for you all.
It was the turn of UX Cassiopeiae to be found and observed.
It was fairly easy to locate as there are plenty of field stars near it.
Guide 9.1 DVD helped me to find this carbon star
Starhopping was not a problem.
The triple star Struve 10 is in the same field of view.

I got my first glimpse of UX Cas at a mere 40X, but as usual I increased the magnifications up to 280X this time. (The time was about 19 UT.)
I found the star as a quite intense orange point of light which I consider very nice. Its spectral class is C6.
Therefore I would very much recommend UX Cas to anyone who loves carbon stars.

The famous website www.aavso.org state that this star is a short semi-regular giant which varies in magnitude from 9.5 to 11.5.

Because of the Purkinje Effect, I slightly put the star out of focus and I estimated its current magnitude as 10.5 on this occasion. I have recorded that estimate on www.aavso.org

It's the 14th carbon star I have observed in the big "W" - and my 91st overall.

Thank you for reading my report.

Clear skies from Aubrey.

Hi Aubrey, 

Fantastic observational report from you. Congratulations on reaching Carbon star number 91...you're motoring along since that minor bump in road a while back. Are you thinking you'll get to 100 by the end of the year? 

Your report on Mars is brilliant, particularly seeing that I was observing it from midnight on Saturday for about 30 mins. I did notice some shading, but I couldn't establish what feature it was from 'Starry Night 7'. Like you I did identify the SPC... It was considerably smaller than a few weeks ago though. Also, I did notice a whitish band at the northern limb, but wasn't sure what it was. Thanks to your observational report I assume it was the North Polar Hood. 

I didn't notice the double star near by either: (

As for the 'Purkinje Effect' that's a new one for me... You never cease to enlighten me Aubrey... Great stuff, and clear skies, 

Darren. 

Thanks for the wonderful observation reports.    You must take as much time to write up these reports as the time spend viewing them.  

regards
Stephen

Yes. I can understand you thinking that, Stephen.
But I do copy from my reports on www.cloudynights.com
I start with that website first.
Then I fairly well paste them here with a few additions on www.irishastronomy.org .
I do the latter because I have the desire to encourage Irish amateur astronomers to join in with their own astronomical pursuits and reporting on such celestial objects here.
Therefore I do very much thank you for your encouraging remarks.
Please keep them coming, Stephen.
Thank you very much.

Clear skies to you (whenever they occur) from Aubrey.

I notice that Aubery, I see your reports on Cloudy night also. I too do a lot of observing, my field is off the beaten track though, I look for exploding stars ie. Novae, especially the recurrent ones that are few and far between. I have been doing this for nearly 20 years, and have yet to catch one. I reguarly report in my observations to the AAVSO, and since I have found none yet, i don't write about them here or anywhere, it would bore the pants off most people

Keep up the good work !

Keith..

Em... - I don't think anyone's reports on recurrent novae would bore the pants off everyone, Keith.
Although I have only observed 2 novae over the years, I still find these objects wonderfully fascinating. And I'm sure I'm not the only one.
So please do report on them here, Keith.

Clear skies from Aubrey.