Observations - 24th June 2020

Hello, everyone.

As you all know, I own a William Optics 158 mm F/7 apochromatic refractor.

1. On Wednesday 24th June 2020 I observed a 3.5 day old crescent Moon in the western sky before and after sunset for over 1 hour. Sunset at this time of year in Dublin, Ireland occurs at the latest possible time of 21.57 Irish Local Summer Time. So from here on, our sunsets will be getting a little bit earlier after each night. I did not go beyond 112X on the Moon. For the record, the magnitude of Luna was -8; an illumination of 14%; an angular diameter of 32'; its distance = 373,181 kms from Earth. The highest magnification I used was 112X - as the seeing was not great. Some of these lunar features I have observed before; but quite a few I have not. I use Antonin Rukl's Atlas of the Moon at all times.

I shall start with the ones I have seen before. As Mare Crisium was clearly visible, I thought I ought to ignore the terminator for a change. Mare Crisium was most certainly closer to the lunar limb on this occasion because of lunar libration. Cleomedes (126 km), A (12 km), Tralles (36 km), Debes (31 km), A (33 km), B (19 km), Macrobius (64 km), Tisserand (36 km), the triple crater Burckhardt, (57 km), E (39 km), F (43 km), Langrenus (132 km) with its 2 central peaks, Petavius (177 km) + Rimae Petavius (80 km), Wrottesley (57 km), Vallis Palitzsch (110 km), Hase (83 km), A (15 km), Palitzsch (41 km) and Furnerius (125 km), B (22 km).Each of these I have observed before over the years.

But the features I have not seen before are these:

Legendre (78 km) is a very shallow crater. Its rim is extremely difficult to see - especially as it is near the limb. But I got it okay. Adrien Legendre (1752-1833) was a French mathematician.
Adams (66 km) + B (28 km) + D (42 km) are new to me. But I am particularly pleased to have now observed these 3 craters as they are named after John Couch Adams (1819-1892) who made the calculations for finding the planet Neptune in the Solar System. Having observed many times, I am a little bit embarrassed it has taken this long for me to finally see himself on the Moon. Of course Urbain Le Verrier was the man who eventually discovered the planet in 1846.
Fraunhofer (57 km) is another crater I should have found before. However it's better late than never. Its satellite craters V (24 km), A (29 km) and H (43 km) are all first time observations for me. Joseph Fraunhofer (1787-1826) was the discoverer of the lines in the solar spectrum.
Furnerius Q (30 km), K (36 km) and H (44 km) were even closer to the limb when compared to the main Furnerius crater. If you find his name rather scary, his real name is much more friendly. Georges Furner who lived in the 1640's was a French Jesuit priest and a mathematician. Little else is known about him.
Lastly, the closest set of craters to the lunar limb I observed on Wednesday night belong to Marinus (58 km) and its almost completely joined up set of satellite craters. A (27 km), B (59 km), C (37 km), D (51 km) and R (44 km). Only D is somewhat detached from the others. Marinus of Tyre lived way back in time during the 2nd century AD. He was a Greek geographer who was the first to point out that Asia and Africa might be larger than Europe. This meant the Roman Empire did not govern the whole world at the time.

I probably would have observed some other lunar features; but I was very keen to split some doubles in Corona Borealis.

But never mind! I would say I did have a very good time finding these lunar features.

Having observed the Moon for over an hour, I set out to observe 3 doubles and 1 triple star all within the confines of Corona Borealis from 11 pm to midnight.

Success was to be had with each one I observed.

All are south of Iota Crb.

All figures can be found on www.stelledoppie.it

2. STF 2029 which is a true binary and is west of Upsilon Crb. Magnitudes: A = 8. B = 9.6. Sep = 6". PA = 187 degrees. Nice easy split at 112X of course. But I thereafter I found I easy split it at 40X. I did increase to 167X and I was soon to notice that B had an orange hue. A was white. This was the only time I saw an orange star during this hour.

3. STF 2022 is also a true binary. Magnitudes: A = 6.5. B = 10. Sep = 2.5". PA = 153 degrees. This is a reasonably tough double to split. But 167X and 225X did it justice I am very happy to say. The delta mag of 3.5 had to be overcome. By the time I successfully split it there was already a decent black gap between the 2 stars. The colours are yellow-white and white. So nothing fancy here with the colours. However I did admire the view all the same.

4. STF 2011 is the only triple of the night. And it seems that all 3 stars are uncertain binaries. Magnitudes: A = 7.9. B = 10.2. C = 9.5. Sep = 2.7" and 118.1". PA's = 67 and 350 degrees. A and C were easily split at 40X of course. But to see the B star 112X gave a good tight split. At 140X was a delightful split too. All 3 stars were white to me.

5. Finally, I observed an uncertain double called AG 349. Magnitudes: A = 9.6. B = 10.9. Sep = 11.7". PA = 228 degrees. A dim pair but nicely split at 112X. AG stands for Astronomische Gesellschaft.

So there you have it. Nothing terribly exciting this time.

But I was so relieved to do some observing.

I have since discovered there are 4 more doubles in Corona Borealis for me to seek out.

After that the Northern Crown and I can go our separate ways.

But what an amazing constellation it truly is!

By the way, this observing session was my 50th of 2020.

Comments are very welcome.

I wish you all clear skies from Aubrey.

Very many thanks for another great observation report Aubrey. Your Lunar report was excellent to read, I really enjoyed reading the historical details about each crater. Big congratulations on observing many new lunar features too!

Also your reports on Corona Borealis are always fascinating, and this one was no different. It is a delightful constellation that I enjoyed spending time in this Spring. While I can no longer observe it from my observing spot in the back garden, your reports on it have allowed me to continue to learn about some of its treasures - thanks Aubrey!

I did a little bit of observing on Wednesday evening myself. Unfortunately, the clouds were moving across the sky rather quickly. So, it was a rather trying session. In saying that, I did get my first view of M57 of 2020. It was difficult to make-up out its ring shape though. I also attempted to find M56, but I failed miserably! So, that's next on my list. I finished-up at 00:18 UT+1 with Albireo. Better than nothing I suppose.

Clear skies,

Darren.

 

Another excellent report indeed Aubrey; the history lessons were almost as interesting as the observations! Rukl's Atlas seems to serve you very well but here's the IAU site listing every named crater on the Moon:

planetarynames.wr.usgs.gov/SearchResults...pe=Crater,%20craters

Finbarr.

Until_then-Goodnight! wrote: Very many thanks for another great observation report Aubrey. Your Lunar report was excellent to read, I really enjoyed reading the historical details about each crater. Big congratulations on observing many new lunar features too!

Also your reports on Corona Borealis are always fascinating, and this one was no different. It is a delightful constellation that I enjoyed spending time in this Spring. While I can no longer observe it from my observing spot in the back garden, your reports on it have allowed me to continue to learn about some of its treasures - thanks Aubrey!

I did a little bit of observing on Wednesday evening myself. Unfortunately, the clouds were moving across the sky rather quickly. So, it was a rather trying session. In saying that, I did get my first view of M57 of 2020. It was difficult to make-up out its ring shape though. I also attempted to find M56, but I failed miserably! So, that's next on my list. I finished-up at 00:18 UT+1 with Albireo. Better than nothing I suppose.

Clear skies,

Darren.

 

Hello, Darren. Thank you for your compliments. You might inform us what you did see in Corona Borealis. I had forgotten you spent some time in this constellation. 

But I am so pleased you are acquainting yourself with M57 and Albireo once again. 
M56 is most certainly a tough globular to find. A dark site will help.  
As a star hopper, I do need some patience to see it. 
But I have succeeded in the past. I even showed it to a Brazilian couple. 

Best regards from Aubrey. 

Fermidox wrote: Another excellent report indeed Aubrey; the history lessons were almost as interesting as the observations! Rukl's Atlas seems to serve you very well but here's the IAU site listing every named crater on the Moon:

planetarynames.wr.usgs.gov/SearchResults...pe=Crater,%20craters

Finbarr.

Thank you, Finbarr for your compliments also. 
And a huge thank you for posting that link by the IAU. 
I wonder if it comes as a type of book. 
It probably doesn't.
But what if it did?

Kind regards from Aubrey. 

Hi Aubrey,

You're more than welcome. I always love reading your reports. Shame we haven't had more clear nights in June, hey?

And speaking of months, I spent most of my April and May nights observing / starhopping in Bootes, Coma Berenices, Hercules, and Corona Borealis. The stars I observed over those two months in Corona Borealis were:

Alphecca, Gemma
Gamma Coronae Borealis
Delta Coronae Borealis
Epsilon Coronae Borealis
Nusakan

On Monday 11th May I observed what looked like a nice grouping of stars in Corona Borealis: Those stars included:

R Coronae Borealis
HIP 77373
HIP 77479
TYC - 2039 - 242 - 1
TYC - 2039 - 951 - 1
TYC - 2040 - 297 - 1
TYC - 2040 - 957 - 1
TYC - 2040 - 743 - 1

I must admit I am missing the dark skies of Co. Wicklow. I suppose it won't be too much longer before we're back under those lovely skies again - fingers crossed!

Kindest regards,

Darren.