lunator

Yep, the book is inspired by the Sissy Haas book.🙂

I own it and have used it. My only frustration was the labelling of the pairs selective and so I sought to standardize on SAO/HD numbers where possible.

Here are a couple of pics of the inside of the book. 

I hope they are clear enough.

Cheers

Ian

It is available at FLO now 🙂

Cheers

Ian

The doubles listed in the book are data entries. 

I only have a few dozen images. 

The core of the book is the 2000+ data entries with accurate information from the WDS including additional components.

Many books list a main component and completely miss out another one that might be closer or fainter. 

I would love to produce a book with all my photos and sketches but that would run to several volumes 😁.

Very good sketches

Hercules does have some lovely doubles to view.

Cheers

Ian

A managed to get the 200mm dob out for a quick session. I used Vega to  check on the alignment of the finder and then ad a quick look at M57. At  x37.5 it appears as a pale grey circle.

A few doubles in Her.
STF2165AB w/b A fairly wide pair the primary is white, the secondary is pale blue. 
STF2165AC w/nc 'C’ Component lies some distance away

STF2301 y/y A wide pair if yellow primary and a pale blue secondary. Very rich field.

STF2309 w/w A close pair of white stars, just split at x60. Best view at x100 magnification.

STF2312 w/w A close pair of white stars. Split at x150. A small difference in magnitude. 

STF2360 w/b A close Pair with a white primary and a pale blue secondary. Part of a neat right angled triangle asterism.

STF2399AB w/w A neat triple The primary and secondary are white. Part of a triangular asterism. With SHY309 
STF2399AC w/nc The ‘C’ component is fainter and doesn’t show any colour.

A few doubles in Serpens
STF2324 w/w A close pair of white stars just split at x150. A similar bright star lies some distance away.

AG224 w/nc A wide uneven pair The primary is white, the secondary shows no colour. Shares field with STF2361.
STF2361 w/w A wide pair of white stars with a slight difference in magnitude.

Cheers Ian

I'll have a look. 

I have split STF1768 but it took x180 to get a nice clean split. This was using a 10" scope so not really a challenge 😁

That is an excellent result.

For the 60mm you should be able to split pairs separated by ~1.9" and a delta Mag of ~2-2.5.

I'll have a dig into the WDS to see if there are any suitable pairs.

Cheers

Ian

Hi The 60mm kid

This looks afun project. I don't have any suitable scopes but will follow with interest.

From experience of using my 70mm scope you can push the mag to x140+ on a good night and should be able to observe pairs down to 2" with a Delta M of 2.5.They won't be split but they will be 2 objects.

It will be hard but rewarding 😁

Cheers

Ian

Hi John, It is a lovely part of the world.

I was enjoying the general darkness. Being back in Bucks just reminds me how bad LP has got over the last  10 years.

I hope to enjoy darker skies once I have moved but it looks like I will be South of the A303 so it little bit away from the levels.

Cheers

Ian

4 hours ago, Mr Spock said:

I'll have to disagree. Near enough isn't good enough. So many people are convinced you can't get above x200 as you can't see anymore detail due to seeing. However we do get good seeing and most of that misconception is people trying to use mis-collimated scopes. A 7mm eyepiece gives x217 in my 12"; that is the lowest magnification I've used, and that is in poor seeing.

You are free to convince yourself of whatever. Meanwhile I'll be cruising the moon's surface, razor sharp, at x461, in good seeing conditions, and wondering what all the fuss is about 

I have to agree. I have an F6 200mm Newt. It used to be on a GEM. If you got the collimation spot on and the seeing was good then the performance of the scope was amazing. It is worth the effort to aim for the best collimation you can.

It will be available very soon. 😁

Cheers

Ian

I had a week on the Levels in Somerset. A cottage in Henley. 

The skies were listed as Bortle 4, but we're right in the limit of 3.

There was a small amount of light pollution form Bridgwater in the North West and Street to the North East.

I managed to get out on 3 nights couldn't stay up too late as the the trip was also a bit of a house hunting trip 🙂.

On all 3 nights the Milky Way was clear and the dark dust lanes were very obvious. Although I had an observing plan I spent a lot of time with the 32mm/70° eyepiece which gave ~1.9° TFOV just sweeping along the Milky Way marveling at the sheer number of stars.

M13 looked like a bright ball of stars at the low mag individual stars weren't obvious. Stopped off at Cor Caroli on my way to M51.

I had my second best view of M51. Some definite structure and the bridge was obvious. (The best was SGL2 in the Brecon Beacons. 12" telescopes vs my 8" and slightly darker skies and younger eyes 😁)

I did observe 4 doubles as that's what I do 🙂

100.Herc. A beautiful bright double. A definite showpiece.

STF1702: A wide pair with a moderate difference in magnitude. The primary is yellow, the secondary pale blue.

STF2159: A wide pair with a moderate difference in magnitude. The primary is white, the secondary s pale orange. A fairly rich field

STF2165: A fairly wide pair of uneven magnitude. A white primary and a pale blue secondary. A 3rd stars lies some distance away..

Cheers

Ian

I still have mine. I have used it for measuring doubles. Definitely a useful eyepiece 

Cheers

Ian

I've has a quick look at the orbit and it is at apastron in 2023. It is at 0.819" and will begin to close later this year.. The orbit is graded 2 so is pretty good. 

Cheers

Ian

Hi John very well done. The Dawes limit on your scope would be around 0.9 so a brightening on the first ring sounds about right. 

I haven't tried for B component but it is something I should put on my to do list. :).

I have found for close pairs that for a magnitude difference of around 2 you can get pretty close to the Dawes limit. This pair has a delta M of ~3 so I think you were pretty close to the limit of what is achievable.

Cheers

Ian

16 hours ago, Agerskov said:

So you are a true Struve specialist. 

But what about the lists - have you written those too?

I see that The List of Double Doubles lacks The Double Double's Double named and discovered by Peter Palagonin who wrote about it in the Sky & Telescope 1998 July issue with with the two doubles STF 2470 and SFT 2474. The four components of this double double is easier to split in smaller telescopes than The Double Double.

I will have to add the in. I should spend more time updating my website but I prefer observing

I did write the lists. I always say my knowledge is extensive but not totally comprehensive

Cheers

Ian

Excellent pics.   It is a lovely part of Wales

My 3 scopes are F5, F6 and F9

They all have their place but for being the best all rounder I have found anything better than my F6 newt.

Cheers

Ian

20 minutes ago, Agerskov said:

Thanks for your answer.

Also STH for Hermann von Struve son of Otto von Struve and STG for Georg Hermann Struve son of Hermann von Struve.

BTW your book is no longer listed at FLO. 

PS - Have you created the lists on your site which are uploaded to Scribd?

The book will be be available soon at FLO. 🙂

I haven't looked at these 2 Struves.

I have about 3-400 struve doubles left to view. So I can add these in. 

Cheers

Ian

I have just checked my Double Star Astronomy book by Thomas Lewis Who was Secretary of the RAS. 

Strive started observing in 1813 and published his first catalogue of 795 double stars in 1822. 

The Catalogue covered the period from 1813-1820. Using a 5 foot Broughton. The aperture was not noted. 

It was called Catalogue 795 stellarum Duplicium.

Apparently 500 pairs were closer than 32" 

In 1824 he got the better Fraunhofer that.allowed him to really take things further.

He produced another catalogue in 1827 'Catalogue Norvus'

All this work was included in the main catalogue 

"Mensurae Micrometricae"  produced in.1837.

It contains 2640 double stars. Numbered upto 3134. 494 were rejected for various reasons.

Hope this helps.

Cheers

Ian

Also some struve doubles had been observed by others such as William Herschel so it may be a reference to that.

The the Strives the WDS has them as

As STF, STFA, STT and STTA.

They are generally visible in RA order ( Proper motion not withstanding ) although the STF3XXX range are more spread around.

Cheers 

Ian

I am mostly a visual astronomer and I still very much enjoy finding objects and teasing out details. I do have astro cameras but have never wanted to image faint fuzzies, I do enjoy trying to tease out planetary  detail. 

I would recommend starting with visual but imaging with a colour camera is a good way to see if it is for you.

Cheers

Ian

I have just checked my Uranometria 2000 star Atlas and STF 2021 is marked as a double but no other designation is given.

Cheers

Ian

Here is the information from Herchel's double star catalogue from the Cambridge University Archive.

H I 82 49 Ser 16133+1332 STF 2021 AB 3/7/1783 1783 2009 402 292 356 64 2.5 4.1 1.6 7.43 7.48 0.05 16 13 18.45 + 13 31 37.2

Data from WDS2010

Herchel Notes

Double. The most north and following of two stars. A little unequal. Both pr.

Bruce MacEvoy Note

Precessing Flamsteed's 1690 coordinates places 49 Ser just inside Hercules: it is labeled in MSA (Millennium Star Atlas) 

My note

It appears it was considered part of Serpens but when the boundaries were officially agreed in the 1930's it was in Hercules.

It has quite high proper motion and is heading towards Ophiuchus but it won't get there for another 90,000 years or so

Cheers

Ian