Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

A Night of Good Seeing in Hercules

  • Please log in to reply
10 replies to this topic

#1 nerich

nerich

    Viking 1

  • *****
  • topic starter
  • Posts: 662
  • Joined: 11 Jun 2016
  • Loc: Greensboro, NC

Posted 20 May 2024 - 04:26 PM

Hello Friends, 

My forecast predicted steady skies last night, so yesterday afternoon I eagerly prepared an observing list that included some close and moderately challenging objects. I was not disappointed! I spent most of the night in Hercules, with one excursion into Draco.

 

I began easy with STF 2063 (5.7/8.7, 16"). This pair is also William Herschel's H IV 62. At 45x in my 150mm Maksutov (3.3mm exit pupil), I noted a PA of S/SW and saw the colors as white and bluish-grey (A is spectral class A2, and B F9). Raising the power to 72x (2.1mm exit pupil) brought out a spectacular turquoise hue in B, although the color fluctuated a bit depending on where I focused my vision. I noted that two ~9th magnitude field stars formed a slightly angled hinge pointing west, with the more distant of the two stars just fitting in the FOV of my 25mm Orthoscopic with STF 2063 centered. A and B share proper motion and are thought to be physical, although WDS gives no orbital solution (the separation and PA are very much the same as they were in the 19th century).

 

Next was the slightly more unequal STF 2024 (5.9/10.7, 24"), Herschel's H IV 115. The first thing I noticed was A's beautiful creamy orange color owing to its K4 spectral class. B was quite dim but perfectly apparent with direct vision. I noted the PA as NE. At 72x, I noticed a third star in the vicinity, at a similar PA as B but about a magnitude dimmer and quite distant (I estimated about 150" in my notebook). Searching on Simbad today reveals that star to be TYC 3064-280-1, with a V-mag of 11.7 and a distance of 181" from A. STF 2024 is also physical, although again no orbital solution is available. 

 

Having warmed up my eye, I moved on to some closer pairs. STF 2030 (7.9/10.2, 5.7") is a very delicate object, with B just a mote of glitter next to A. With last night's waxing gibbous moon washing out the sky, the pair seemed even more fragile. I noted the PA as W/SW. Raising the magnification to 72x gave me white on A (Simbad says A0 for the spectral class), but still no color on B. This is also a physical double, and is very beautiful and gossamer object. 

 

STF 2107 (6.9/8.5, 1.4"), although not the closest pair of the evening, was the most challenging visually. At 1.4 seconds of arc from the primary, B is close to the first diffraction ring in my obstructed 150mm telescope. At 72x, I noted the soft yellowish color of the primary (Simbad gives class F4), and occasionally saw a bump pointing East. At 100x (1.5mm exit pupil), B was consistently apparent, although more as a brightening of the E/SE area of the first diffraction ring than as a discrete object. 200x (0.75mm exit pupil) brought out the spurious disc of B clearly. I'd be curious to hear what those of of you with unobstructed telescopes make of this object! 

This pair is again physical, and this time an orbital solution is available. Stelle Doppie gives us a beautiful graph of the orbit, for those interested. B has a period of only 275 years, and it's at least possible to visually track a small change in PA over the course of a few decades. For instance, in the year 2000, B had a PA of about 97 degrees, whereas in 2030 the PA will be about 111 degrees.

 

STF 2049 (7.3/8.1, 1.1") was my last Hercules double of the evening. Skipping the low powers, I started at 100x, and was treated to a perfect lacy white snowman with a PA of S. At 144x (1mm exit pupil), a thin black line came and went, while 200x split the pair cleanly and consistently. I revised my PA estimate to S/SW, and remarked in my notes how good the seeing was. The atmosphere undulated, but slowly and gently, with no breaking up of the diffraction rings. As for their physical nature, this pair is uncertain. 

 

To end the night, I moved over into Draco for STF 2118 (7.1/7.3, 0.9"). This is Herschel's H I 19, and is more commonly known as 20 Draconis. Admiral Smyth calls this object "very difficult," and quotes Herschel as saying "It is vain to look for them if every circumstance is not favorable." It's worth noting that the separation was tighter then: the elder Herschel estimated 0.5" in 1781, with his son John giving 0.63" in 1830. Struve gives 0.85" and 0.71" for 1832 and 1836, respectively, agreeing with the Admiral's 0.8" and 0.7". As of the present day, WDS gives a separation of 0.899" and a grade 3 orbital solution with a period of 321 years. 

At its current separation, this is a perfectly manageable object for small telescopes, provided the seeing is good. At 100x I noted the nice yellow color (F2 spectral class) and saw an elongation E/NE. 144x gave me a snowman, with 200x notching the pair even deeper. Dropping in the 6mm eyepiece for a power of 300x (0.5mm exit pupil) fully separated the stars. I again noted how steady the seeing was, and took several minutes to admire the ethereal scene. 

 

That's all for now. Comments and corrections most welcome! 


  • VanJan, R Botero, CelestronDaddy and 5 others like this

#2 R Botero

R Botero

    Fly Me to the Moon

  • -----
  • Posts: 5,384
  • Joined: 02 Jan 2009
  • Loc: Kent, England

Posted 21 May 2024 - 06:36 AM

Great write-up El :waytogo:  

 

Roberto


  • flt158, nerich and CHnuschti like this

#3 scoale

scoale

    Viking 1

  • *****
  • Posts: 813
  • Joined: 02 Aug 2021
  • Loc: Triad, NC

Posted 21 May 2024 - 09:55 AM

Had a rare night of good seeing here in the Triad last night and I took the opportunity to chase a few of the doubles in your write-up, as well as revisit a couple of targets I have been observing this spring.  Given the solid 4/5 seeing, I decided to go with my 180 Mak and Mewlon 210.

 

I started the evening with the 180 Mak.  Temp was a very nice 68 degrees with 74% humidity.  I aligned on Polaris and Spica at 207x.  I could immediately tell the seeing was steady but defocusing on Spica also indicated significant collimation error as a result of a heat plume.  Fortunately, the scope had been cooling over an hour and within another 15 minutes was markedly improved.  Regulus at 337x was my next confirmation of how good the night was going to be.  There was still just a hint of a thermal related plume in focus, but an otherwise beautiful airy disk with multiple concentric diffraction rings.  The scope was ready to start pursuing doubles!

 

I started with Omega Leonis at 337x and was rewarded with a stable black space split with a faint outer ring - easily the best view this year of this .9 separated double.  I have previously viewed this double this spring with my TEC 140, SVX 127, and Mewlon 210, but tonight's seeing and view was definitely the best.

 

Next up was Algieba at 337x, simply because I already had the 8MM Delos in the diagonal.  Although this is more power than I would typically use on Algieba, the view was rewarding with two adjacent airy disks both showing multiple diffraction rings.

 

From there I went to Alrakis in Draconis which appeared like two eyes, or car headlights, of near equal brightness, at 337x.  Very nice.

 

Izar was colorful and stunning at 337x.  I do have other eyepieces, LOL, just a bit lazy last night and the seeing was supporting the higher power.

Overall, great seeing, great views, and I was super impressed with the Mak.  Aside from the obvious differences inherent in how airy disks present in a refractor versus a compound obstructed scope, you would be forgiven for believing you were observing with a refractor.  Great scope and, more than once, I found myself wishing Jupiter was up.

 

At 1030 I switched to the Mewlon 210, which had now been cooling several hours.  Arcturus at 301x showed a very nice airy disk, confirming the seeing and that the collimation was on point.  From there I went to STF 2118 and achieved a black space, stable, split of this .9 double at 301x.  Very nice!  From there I went to STF 2049.  I thought this 1.1 double appeared best, and black space split, at 402x - though I was seeing more turbulence at this power.  I left the 6mm Delos in and revisited Izar which was stunning at 402x - though the first ring appeared a tad brighter on the east side versus the west- which could indicate a bit of collimation opportunity, collimation shifting as Izar was at 77 degrees, or residual thermal impact.  The affect was far less noticeable when I revisited Alrakis.  Overall, very satisfying views.  

 

 I wrapped-up at 1130 with the temp now at 63 degrees with 82% humidity.  Summer's coming!


  • VanJan, R Botero, flt158 and 2 others like this

#4 nerich

nerich

    Viking 1

  • *****
  • topic starter
  • Posts: 662
  • Joined: 11 Jun 2016
  • Loc: Greensboro, NC

Posted 21 May 2024 - 01:20 PM

Great write-up El waytogo.gif  

 

Roberto

 

Thanks Roberto! grin.gif

 

 

Had a rare night of good seeing here in the Triad last night and I took the opportunity to chase a few of the doubles in your write-up, as well as revisit a couple of targets I have been observing this spring.  Given the solid 4/5 seeing, I decided to go with my 180 Mak and Mewlon 210.

 

 

Thanks for sharing! Glad you got to take a look at 2118 and 2049. And glad to meet another happy user of the Synta Maksutov. I'm on my second 150mm (the first was damaged in a cross-country move). It's been a great telescope for me. 

Looks like our skies will be clear again tonight, although the seeing forecast looks only average frown.gif



#5 flt158

flt158

    Soyuz

  • *****
  • Posts: 3,697
  • Joined: 11 Aug 2014
  • Loc: Dublin, Republic of Ireland

Posted 21 May 2024 - 01:47 PM

Superb report from scoale I must say. 

You must give us more. 

Your scope is an excellent scope for these tight doubles. 

 

Thank you from Aubrey. 


  • nerich and scoale like this

#6 scoale

scoale

    Viking 1

  • *****
  • Posts: 813
  • Joined: 02 Aug 2021
  • Loc: Triad, NC

Posted 22 May 2024 - 10:38 PM

Thanks Roberto! grin.gif

 

 

 

Thanks for sharing! Glad you got to take a look at 2118 and 2049. And glad to meet another happy user of the Synta Maksutov. I'm on my second 150mm (the first was damaged in a cross-country move). It's been a great telescope for me. 

Looks like our skies will be clear again tonight, although the seeing forecast looks only average frown.gif

 

Hi!  Last night was true to 3/5 forecast - definitely not as good as the previous night.  But any night out is a great night!  For last night's session, I went with the TEC 140 and Mewlon 210.  I wanted to compare the two scopes on some of the tighter doubles.  My observing notes from last night:

 

Started at 9:10 PM; still dusk and just able to see Polaris.  Aligned TEC on Polaris and Spica at 280x.  Airy disk dancing a bit as seeing is not up to last night's standards. 

 

Regulus, at higher altitude and above some of the seeing, displays a better airy disk at 326x. Encouraging.

 

Omega Leonis is notched during more stable moments at 326x but never quite black space split. I try pushing the magnification to 392x but no joy.  I had a better view of OL with the TEC a few weeks back but the seeing limited tonight's view.

 

Etamine in Draco is a brilliant gold at 326x.

 

Alrakis at 326x is less stable than last night - but still pleasing - with a fairly complete ring enclosing the primary and secondary.

 

I try for STF 2118 but am only able to achieve a notch spit during moments of better seeing.

 

Izar is nice at 163x and very nice at 196x.

 

I switch to the Mewlon at 10:15 PM.

 

I black space split STF 2118 at 402x.  The split is clean and surprisingly stable with a faint ring around the stars.  Far better than what I was able to achieve with the TEC.  The Mewlon's aperture is helping but the extra aperture also picks up more of the turbulence, so I am quite pleased with the view.  

 

Izar is quite nice at 301x. Solid airy disks with beautiful color and the companion strikingly positioned.

 

After observing a few more targets I wrap-up at 1130 with temp at 68 degrees and 78% humidity.

 

I appreciate you introducing me to a couple of new targets that I will certainly return to in future years.


Edited by scoale, 23 May 2024 - 12:59 PM.

  • payner, Sasa, flt158 and 1 other like this

#7 scoale

scoale

    Viking 1

  • *****
  • Posts: 813
  • Joined: 02 Aug 2021
  • Loc: Triad, NC

Posted 22 May 2024 - 10:46 PM

Thanks Roberto! grin.gif

 

 

 

 And glad to meet another happy user of the Synta Maksutov. I'm on my second 150mm (the first was damaged in a cross-country move). It's been a great telescope for me. 
 

I have been truly impressed with my Synta Maks.  The performance on Jupiter is comparable to my very nice 5" refractors, and I am quite impressed with how it performs on tighter doubles.  I'm going to thin the telescope herd because there just aren't enough good observing nights here in the Triad to exercise all of the scopes I've accumulated over the years - but I will hang on to this one.


  • nerich likes this

#8 crsrs

crsrs

    Vostok 1

  • *****
  • Posts: 171
  • Joined: 12 Dec 2009
  • Loc: Elyria, Ohio

Posted 24 May 2024 - 01:40 PM

Fantastic double star tour, thanks for sharing your experience. I've printed this up and it will be on my observing dest for my next outing !


  • flt158 and nerich like this

#9 nerich

nerich

    Viking 1

  • *****
  • topic starter
  • Posts: 662
  • Joined: 11 Jun 2016
  • Loc: Greensboro, NC

Posted 24 May 2024 - 02:33 PM

Fantastic double star tour, thanks for sharing your experience. I've printed this up and it will be on my observing dest for my next outing !

Thanks! Please share what you see! 



#10 crsrs

crsrs

    Vostok 1

  • *****
  • Posts: 171
  • Joined: 12 Dec 2009
  • Loc: Elyria, Ohio

Posted 27 May 2024 - 10:32 AM

I had a great night of seeing conditions with transparency being better than usual in my very light polluted suburban backyard on Saturday May 25th. So I double checked the collimation in my CPC1100 brought out my TBM Planetary eyepieces and eagerly set about your Hercules double star tour.

 

I liked the way you used STF 2063 and STF 2024 as "warm up" pairs. 

STF 2063 was a lovely pair and I too noticed the way the secondary danced between colors...sometimes almost lavender and sometimes more aqua.

STF 2024 pushed a bit further with a lovely yellow primary and a soft little smoke-ball secondary. Averted vision really helped to make it pop into view. A spectacular sight indeed!

STF 2030 showed a white primary with a little gray secondary, again averted vision was useful..

STF 2107 was challenging for sure and I was beginning to feel that "the squeeze is ON". A wave of good seeing revealed the tightly positioned blue/gray secondary next to the lovely pale yellow primary. 

STF 2049 was exciting to see when that thin black line appeared between these tiny white beads! WOW! Took my breath away.

STF 2118 ...as I looked at the data on this this one, I'm thinking "good luck".  I put the target in the eyepiece... stepped up to 311X magnification I could hardly believe my eyes!

I stepped away shocked that I could split that so cleanly. I'm still wearing a grin as I think about it. 

 

What a Fun tour!! Thanks again for offering it up here.


  • VanJan, flt158, nerich and 1 other like this

#11 nerich

nerich

    Viking 1

  • *****
  • topic starter
  • Posts: 662
  • Joined: 11 Jun 2016
  • Loc: Greensboro, NC

Posted 27 May 2024 - 01:22 PM

I had a great night of seeing conditions with transparency being better than usual in my very light polluted suburban backyard on Saturday May 25th. So I double checked the collimation in my CPC1100 brought out my TBM Planetary eyepieces and eagerly set about your Hercules double star tour.

 

I liked the way you used STF 2063 and STF 2024 as "warm up" pairs. 

STF 2063 was a lovely pair and I too noticed the way the secondary danced between colors...sometimes almost lavender and sometimes more aqua.

STF 2024 pushed a bit further with a lovely yellow primary and a soft little smoke-ball secondary. Averted vision really helped to make it pop into view. A spectacular sight indeed!

STF 2030 showed a white primary with a little gray secondary, again averted vision was useful..

STF 2107 was challenging for sure and I was beginning to feel that "the squeeze is ON". A wave of good seeing revealed the tightly positioned blue/gray secondary next to the lovely pale yellow primary. 

STF 2049 was exciting to see when that thin black line appeared between these tiny white beads! WOW! Took my breath away.

STF 2118 ...as I looked at the data on this this one, I'm thinking "good luck".  I put the target in the eyepiece... stepped up to 311X magnification I could hardly believe my eyes!

I stepped away shocked that I could split that so cleanly. I'm still wearing a grin as I think about it. 

 

What a Fun tour!! Thanks again for offering it up here.

 

An excellent report! Love how you describe STF 2024 B as "a soft little smoke ball." And that 11" SCT sounds like a fine star-splitting scope indeed! Glad you were able to check out these lovely objects. 


  • crsrs likes this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics