Observations - 6/6/22

Hello everyone. 

I had splendid clear weather for most of the afternoon and evening over Dublin. 
The Moon was in mid Leo. 
So I set up my William Optics 158mm f/7 apochromatic refractor in my back garden. 
 
The Lunar V was first to appear a full 45 minutes before the Lunar X. Strange!
When the Sun was getting quite a bit lower in the north western sky, I let my refractor loose on it. 
At 9.20pm local time, the X finally appeared. 
My wife then joined me and Darren joined us on the phone. 
 
What I have found particularly thrilling is that I have now observed both these Clair-obscure features TWICE in 3 months. 
The time before was 8th April 2022. 
I have no idea if I could ever repeat such a feat again!

I'm not going to leave it at that though. 

Every one of these craters had completely black centres, i.e., the Sun had not yet shone into their centres. 
Aliacensis (80km), Werner (70km), Blanchinus (58 X 68km), most of Albategnius (136km), Klein (44km), Halley (36km), Horrocks (30km), Pickering (15km), Rhaeticus (43 X 49km), + A (11km), Triesnecker (26km), Hyginus (10.6km), Ukert (23km), Aristillus (55km) + B (8km) and Autolycus (39km). 
No less than 4 rilles were observed: Rimae Theaetetus (50km), Rima Ariadaeus (220km), Rima Hyginus (220km), and Rimae Triesnecker (200km).   
So, all in all, you could say it was a super night observing the Moon for about 1.5 hours! 

This is due to be my final post regarding R Leonis. 
The variable star is now extremely low close to my north western horizon.
I had to wait until after 11pm local time before it finally appeared in both my William Optics 70mm f/6 and my 158mm f/7 apochromatic refractors. 
As the sky darkened minute by minute, R Leo eventually popped out. 
Its rose-scarlet colour was easily seen once again. 
Over on www.aavso.org I have recorded a magnitude of +6.1. 
What a star this is!
On the night of the 7th April R Leo was just +9.0. 
It is now brighter than 19 Leonis (6.4 mag). 
It has been such a privilege to observe this variable for some months. 
I feel a little bit sad that my observations of it have now come to an end. 
But roll on late winter 2023 when I will reacquaint myself with this wondrous star once again.   
 
I close by thanking you all for reading each of my reports, and also for encouraging me personally to observe R Leonis!  
 
I simply have to report on my favourite faint orange - blue double star I have ever observed. 
 
However I must first report I had a successful separation or Izar (Epsilon Bootis) at a mere 112x. 
Magnitudes: A = 2.6. B = 4.8. Sep = 2.9". PA = 347 degrees. 
I could easily see that the primary had its familiar yellow-orange colour. 
But B was simply white at even 167x. 
It's probably because my sky was still relatively bright so soon after sunset. 
Still I was very pleased with this result of separating it at 112x. 
I'm sure in the autumn the secondary will become more in the way of blue.
 
Staying in Boötes, I then starhopped my way north to magnitude +3 Gamma Bootis (Seginus) to find my way to these 2 double stars: STT 276 and HJ 540. 
 
STT 276 is a true binary. Magnitudes: A = 8.5. C = 10.6. Sep = 9.5". PA = 72 degrees. The primary is F4 yellow-white alright. The secondary is white. I had no separation at 40x. But joy was had at 112x. There is no hope for yours truly to separate the A and B of STT 276. It's just 0.4". Still A and C provide a pleasing sight.
 
I can now announce that HJ 540 is my favourite faint orange - blue double and it is a true binary. Magnitudes: A = 9.4. B = 10. Sep = 8.9". PA = 211 degrees. I split it at just 40x first. But I increased my magnification up to 112x. You see, the primary has a spectral class of K0. My wife and I discussed the colour of this star for quite a while. Valerie stated she saw it as a primrose yellow star with just a hint of orange to it. I fully agreed in the end. We both agreed that the secondary is a delightful blue. What is particularly extraordinary is that these 2 stars are seriously faint. I had never thought I would see such vivid colours with a double star so faint. 
 
Thank you very much for reading this report. 
 
Comments are extremely welcome as always. 
 
Clear skies from Aubrey.   

Hi Aubrey, 

That's a mighty fine report and it was great to  observe the Lunar X and V with you and Valerie - I'll post my report over the next 24hours.

I'm delighted that you've monitored R Leonis over the past few months, and I was amazed to hear how it's brightened again. Fair play on brininging it to my attention and recording it on aavso. 

Here's to many more clear nights throughout June. 

Darren. 

Thank you very much, Darren. 

It was a real privilege to have you with us on the phone!

By the way, some folks on Cloudy Nights are going some interest regarding my "new" double star HJ 540. HJ stands for John Herschel. I wonder what Mr. Herschel thought when he discovered this little gem in Boötes. 

After tonight's storm, we might have clear nights on Thursday and Friday - in the Lord's will. 
I have printed off a map from Guide 9 with some more doubles in Boötes. I will need calm skies to split some of them. 

Very best regards to everyone, 

Aubrey. 

 

Hi Aubrey,

That's very kind of you to say, but I'm really enjoying sharing observations with you over-the-phone! Observing and swapping notes with others is great fun.

As promised, here is the photo I took with my phone, which is by no means an expensive smartphone. I had to rezise the image to uplopad here, but the Lunar 'x' and Lunar 'V' can be seen.

Also, you might recall I remarked about that wall-like feature in one of the Southern craters. Well, the good news I have identified it with my Virtual Moon Map (VMM): It's the 'central crest line' in Heraclitus, which is how this fearture is described in the VMM, Rukl'  descibes the feature as a'central mountain range' that runs 90km length. Regardless, this feature looked gorgeous on the 6th of June.

In terms of your new double, I really must get back to Cloudy Nights again to read the comments about it.

Clear skies,

Darren.


  

Hello Darren. 

Thank you for your latest spectacular image of the Moon. 

You're right! Your crater is Heraclitus. I see it on Map 73 of Rukl. 
It's real beauty for sure!

And I see you have imaged both the Lunar X + the upside down V in your Smartphone shot. 

By the way, I'm now receiving reports and images for Orbit. 
So time is getting short. 

Clear skies from Aubrey. 

Hi Aubrey,

Many thanks for your message. I'll send you over a sketch just now.

Clear skies,

Darren.