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42 Doubles in Hercules Observed with AT115EDT

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#1 Rustler46

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Posted 01 July 2018 - 12:47 AM

Here are some recent observations of double stars in Hercules using my Astro Tech AT115EDT APO triplet refractor. I’m about half way through the SkySafari list of 145 double stars in Hercules. Many of the entries are not suitable for the 115 mm aperture - too close or too faint. Others were not good subjects for bright moon nights. A few of these doubles were also observed with both the refractor and a Celestron-8, mounted as seen below.

 

C-8 w- AT115EDT-00944.jpg

 

I've got the refractor mounted well forward to give some separation between the two eyepiece positions. In any case here are 42 double stars in Hercules recently examined:

 

Alpha Herculis
Ras Algethi - 3.5/5.3 magnitudes @ 4.6 arc-seconds, a nice yellow-orange primary, a little red flare off to the side (perhaps due to cool down issues), secondary might be slightly yellowish, quite a bit of dark space between 'em, there are little pieces of diffraction ring showing once in a while, but a real nice double, always well worth looking at this one
Zeta Herculis
2.8/5.4 magnitudes @ 1.3 arc-seconds - after looking at this for a little while (seeing's not real bad - there are diffraction rings part of the time), I'm not seeing anything I can call resolution, sometimes there's a little elongation in the image as it's warping around a little, but I'm not calling this one resolved, there's just too much magnitude difference, mabe seeing is playing a part, but this is an interesting star
Σ 2015
8.4/9.5 magnitudes @ 2.9 arc-seconds, even with some thin clouds I'm able to pick out that little 9-1/2 magnitude secondary, it's hard to see, I'm using averted vision, but it's well separated, can't see any color, it's really compromised as these clouds float through here, we'll count this one as resolved, fairly well shown
37 Herculis
Double star with 36 Herculis - 5.8/6.9 magnitudes @ 70 arc-seconds, a beautiful wide pair, some brightness contrast, the primary to my eye looks pretty white, sometimes I get a little tinge of yellow, there is a field star 10-1/2 magnitude a ways off from the secondary, visible with averted vision maybe 10 arc-seconds distant (11.8 mag. @ 26 arc-seconds according to SkySafari), given the bright moon light it's surprising to see a star that faint, no other discernable field stars in the area
OΣ 307
7.6/10.7 magnitudes @ 17.5 arc-seconds, this one is a little difficult with the bright gibbous Moon, but with averted vision I can see the secondary, well separated, I can't hold it with direct vision, but there it is, resolved, this would be much more interesting if it wasn't a bright moonlit night, but we'll call this one resolved, but it will be worth looking at under better circumstances
Σ 2021
7.3/7.5 magnitudes @ 4.1 arc-seconds, a nice neat little double, very slight brightness difference, a fair amount of dark sky between 'em, the brighter one has a slightly warmer color to it, no interesting field stars nearby, a really neat little pair of "headlights" looking at me
Σ 2025
7.9/9.8 magnitudes @ 2.6 arc-seconds, I can't really say that I can resolve it. Just too bright of a sky, too faint of a secondary right in there close, will save this one for another time
Σ 2040
8.1/10.1 magnitudes @ 7.0 arc-seconds, OK this is a nice neat little double, a bit of a challenge in the bright moonlight, I can almost hold the secondary with direct vision, just slight averted vision brings it right out, there's quite a bit of dark space between 'em, this is a nice double, I'm enjoying looking at it, I'm not seeing any bright field stars anywhere near, but we'll mark this one off, I don't see much of any color in the primary
Σ 2051
7.7/9.5 magnitudes @ 13.8 arc-seconds, well this little guy is easily separated, the secondary is easily held with direct vision, can't tell any real color in the primary, no bright field stars close by, sometimes I get the sensation the secondary is a bit red, but I suspect that's just from its dimness, a real nice double, a lot of separation, a lot of brightness contrast, very nice star images
Σ 2056
7.7/9.2 magnitudes @ 6.7 arc-seconds, a nice double with good brightness contrast, a lot of dark sky between, can't tell much about any color, no close by field stars, a nice little double easily seen under the bright moon conditions
Σ 2062
8.9/10.6 magnitudes @ 2.4 arc-seconds, this is a tough one under the bright moon circumstances, with attention to focus and some intense scrutiny I'm seeing that little secondary using averted vision, resolved with difficulty at 230X. At 146X a little bit easier to resolve, I can more consistently hold that little secondary
Σ 2063
5.7/8.7 magnitudes @ 16.3 arc-seconds, this is just a real neat double, huge brightness contrast makes it very interesting, lots of dark sky between, nice tight star images, that secondary is easy to hold with direct vision, can't see any close by field stars, it just a spectacular double to be looking at, I really like this, bright components
Σ 2068
8.9/9.1 magnitudes @ 5.0 arc-seconds, this is just a neat little double, almost identical brightness, a set of "headlights", plenty of dark sky between 'em, the star images aren't very bright, but it's a cute little double, the fainter one looks a bit orangish compared to the brighter one, a real nice double
Σ 2079
7.6/8.1 magnitudes @ 16.8 arc-seconds, this is an interesting double, well separated, a good brightness contrast, bright enough to be easily seen, there's quite a number of interesting field stars, one about 8th magnitude out there (2/3 of the field radius), there's a 9th magnitude one out there a little bit closer in, but the primary looks a little bit yellowish compared to the secondary which has a slightly bluish cast to it (the colors end up changing, so not very reliable), we'll call this one resolved, well worth looking at, a real nice double
Σ 2083
9.0/9.6 magnitudes @ 12.7 arc-seconds, yeah this one is a little bit faint but both components are easily seen with direct vision, a lot of dark sky between 'em, no colors discernible, the pair is part of an isoceles right triangle, the vertex is about 10th magnitude, the double is at one of the equal length sides, the other star is about 10-1/2 magnitude, it's not quite a right angle a little bit less than 90 degrees, a nice neat little double in an interesting arrangement of field stars, pretty well shown despite the bright sky
Σ 2085
7.4/9.2 magnitudes @ 6.3 arc-seconds, ah this is a real interesting fairly close little double, I can hold the secondary easily with direct vision, huge brightness contrast, well separated, the double is part of an isoceles triangle of field stars that are way way out there, the vertex is about a 10th magnitude star, the double is over there on one of the sides, the star at the end of the other side is about 8th magnitude, there's another field star that shows with averted vision outside the triangle, kind of a neat little double, sometimes the secondary is hard to see and at other times it pops right in there (maybe a cloud or fog on the eyepiece), we'll call this little guy resolved
BU 627
4.8/8.5 magnitudes @ 2.1 arc-seconds, well I'm going to call this guy resolved, it's not pretty, seeing's not real good (dew heater might be turned up too high), the primary is there kind of boiling around a little, the little secondary is real close in there, I can't say there's a whole lot of dark sky between, huge brightness difference, but I'm seeing them separated, the two discs are in contact with not much space between, I suspect there would be more separation with better seeing conditions
OΣ 318
6.8/9.6 magnitudes @ 2.9 arc-seconds, well this is a pretty neat little double, huge brightness difference, but 3 arc-seconds is good enough to get that little secondary out there, there's a little dark sky between 'em, the primary maybe has a little bit of a yellowish look to it, I can hold the secondary with direct vision, but it's a little better if I go just a bit off from direct view, no close by field stars

OΣ 318      (another night's observation)
6.8/9.6 magnitudes @ 2.9 arc-seconds, suspected seeing the secondary at 146X, with 179X, yeah that little secondary is right there well separated, primary looks a little yellowish or a bit toward orangish, but a nice little pair, no interesting field stars nearby, but we'll call this little guy resolved
Σ 2087
8.7/8.8 magnitudes @ 5.6 arc-seconds, sometimes I get the sense that the fainter component is slightly red, but nothing real definite, a nice little neat pair of "headlights", well worth examining
Σ 2094
7.0/7.9 magnitudes @ 1.1 arc-seconds, with some extensive scrutiny best I can say is it has kind of an elongated image, sometimes I suspect seeing a couple of discs in contact, but I'm not really going to call this one resolved, there is an 11th magnitude companion at 22 arc-seconds nicely visible
Σ 2095
7.3/9.2 magnitudes @ 5.2 arc-seconds, yep that little guy is here, a large brightness contrast, good separation, a fair amount of dark sky between 'em, I can hold the secondary with direct vision, at 146X a lot more interesting view than with 230X, the primary looks a little bit yellowish, but that color if anything is very slight, I don't notice any nearby field stars, a nice interesting double star well worth looking at, definitely resolved
Σ 2098
8.8/9.6 magnitudes @ 14.2 arc-seconds, well this is very nicely shown, an interesting field, 11th magnitude companion at 66 arc-secs., at about 106 arc-secs. Is a 9.6 mag. star, don't see any obvious colors, an interesting double with two fairly close by companions, well worth looking at
Σ 2101
7.4/9.4 magnitudes @ 4.0 arc-seconds, a real nice little unequal double, well separated with a lot of dark sky between 'em, I can hold the secondary with direct vision even with the Moon shining in the side of my eye, there are a couple of field stars - 10th magnitude at almost 4 arc-minutes out there & 11th magnitude star at 2-3/4 arc-minutes, this is an interesting field, the double is well seen, quite a large brightness difference, easily resolved
Σ 2103
5.9/10.0 magnitudes @ 5.2 arc-seconds, though a little challenging I'm seeing that little 10th magnitude secondary there, it takes averted vision to see it, while detectable at higher power it's not any easier to see, a fair amount of dark sky between 'em, the large brightness difference makes it difficult
Σ 2104
7.4/8.8 magnitudes @ 5.7 arc-seconds, yeah this is a real nice double, really well shown, large brightness difference, there's a 10-1/2 magnitude field star almost in the opposite direction from the secondary roughly an arc-min. away, no other close by field stars, a nice little neat pair
Σ 2107
6.8/8.5 magnitudes @ 1.4 arc-seconds, this has been another tough one, but once again I'm seeing two star discs, not really much dark sky between 'em, looks pretty much in contact, we'll call this one resolved, but with difficulty, there's a 11.3 mag. field star off there at 1-1/3 arc-min.
Σ 2109
7.4/10.3 magnitudes @ 5.7 arc-seconds, couldn't see it at 230X, but with the lower power there it is, widely separated out there, can't hold the secondary with direct vision, but with just a little bit of averted vision it's visible there, no notable field stars or colors on the primary, so I'll call this nice little double resolved
A1874
7.8/7.8 magnitudes @ 111 arc-seconds, this guy is a real wide equal double, both stars look white or maybe slightly yellowish, a huge amount of space between 'em, no nearby field stars of any note, so we'll call this one as having been observed
Delta Herculis
Double star, Sarin - 3.1/8.3 magnitudes @ 12.7 arc-seconds, yeah this is a real nice one, the primary to me looks white, there are some fragments of diffraction rings around there so the seeing is pretty fair, that little 8th magnitude secondary is there way out there, easy to see, the primary sits in the middle of an equilateral triangle composed of 9th manitude field stars about an arc-minute out there, lots of brightness contrast and separation, in an interesting field
OΣ 328
4.8/10.3 magnitudes @ 4.5 arc-seconds, the primary has diffraction rings around it sometimes, but that little secondary I'm seeing it, it's a tough one, but there it is, it's very very faint, there's a little bit of dark space between 'em, but we'll call this one resolved, the primary looks basically white, beautiful diffraction image there,
OΣ 330               (Observed with AT115 EDT and Celestron-8)
8.2/11.2 magnitudes @ 14.5 arc-seconds, With the 115 refractor at 146X:  I'm not able to see that 11th magnitude secondary, it's just too faint for the bright moon conditions, I was able to get a good fix on the position angle as seen in the C-8, but still couldn't see it in this smaller telescope. So under these conditions the extra aperture of the SCT wins out. With the Celestron-8 at 80X that little secondary is visible, I found the best eyepiece for use with the C-8 was the 16mm Koenig, the extra aperture over the 115 mm refractor gave success, I was able to get a good fix on the position angle to help seeing it in the refractor
Rho Herculis      (Observed with AT115 EDT and Celestron-8)
Double star,  Σ 2161 - 5.4/4.5 magnitudes @ 4.0 arc-seconds; With the 115 refractor at 179X:  this is a real spectacular double star, bright, both components look white, the secondary being a little dimmer might have a different tint to it - maybe yellowish, beautiful tight little star images, there are pieces of diffraction rings visible from time to time, no interesting field stars nearby. With the Celestron-8 at 116X there are a lot of flares coming off the star images, I much prefer the view through the little refractor, but we'll call this one resolved, well worth observing 
Σ 2110
6.1/10.8 magnitudes @ 18.1 arc-seconds, I can't say I'm seeing that secondary star at all even with 230X
Σ 2112
8.9/10.3 magnitudes @ 2.1 arc-seconds, yeah that little secondary is right there, it's well separated there, it's got a little bit of dark sky between 'em, both of them are pretty faint, with 179X both of them are real dim but visible, well separated, I'm calling this one resolved, but it's a dim little guy
Σ 2120
7.3/9.3 magnitudes @ 24.1 arc-seconds, yeah this is another nice double, large brightness difference, widely spaced, a lot of black sky between 'em, the primary is close to white maybe a bit yellowish, I can hold that little 9th mgnitude secondary with direct vision, there's a couple of fairly close by field stars - one's about 10th mag. and another about 9th mag. spread at a 150° angle with respect to the primary (at vertex), a nice double well worth looking at
Σ 2135
7.4/8.9 magnitudes @ 8.7 arc-seconds, a nice neat little double, the primary looks a little yellowish, secondary has no color discernable, a lot of dark space between 'em there, no close by field stars, a nice unequal double well worth looking at
Σ 2137
9.1/10.0 magnitudes @ 4.1 arc-seconds, yeah this is a nice dim little double star, the secondary is a bit hard to hold with direct vision, a pretty large brightness contrast, some dark sky between 'em, but it is a dim one, no close by field stars, no color noted in the components
Σ 2142
6.2/9.4 magnitudes @ 5.3 arc-seconds, yeah this is a real interesting one, bright white primary, the secondary is easily seen out there with direct vision, there's a little dark space between 'em, it's got a huge brightness contrast, there's one field star out there about 9th magnitude (about at a 90° angle versus the secondary's P.A.) at 3-1/3 arc-minutes, but it's a nice interesting double, well worth observing
Σ 2147           (Observed with AT115 EDT and Celestron-8)
6.9/11.0 magnitudes @ 3.0 arc-seconds; With the 115 refractor at 179X: well the story with this one is basically not resolved, it is a variable star with an orange color to it, it's paired up with a really wide double star way out there (2-3 arc-minutes) with similar brightness, the refractor gives beautiful little star images but that 11th magnitude secondary isn't visible; With the Celestron-8 at 116X I can see the orange color of the primary, but I'm sure not seeing the secondary, but the primary star image doesn't look as good as the 115 refractor, but to be fair the image is not in the center of the FOV, in any case not resolved
Σ 2160           (Observed with AT115 EDT and Celestron-8)
6.4/9.3 magnitudes @ 3.7 arc-seconds; With the 115 refractor at 146X: there it is, a creamy white primary and that little 9th magnitude secondary is there, I'm having a little trouble holding it with direct vision, but it's pretty much there, huge brightness contrast, a fair amount of dark sky between 'em, an interesting double star; With the Celestron-8 at 142X it was with difficulty I was able to resolve this one, I have to hold my eye just right to reduce the flares around the star images, not a real clean looking image, the little 115 mm refractor comes out on top with this one
Σ 2168           (Observed with AT115 EDT and Celestron-8)
8.7/9.1 magnitudes @ 2.3 arc-seconds; With the 115 refractor at 146X: there they are, a little bit more difference in brightness than I expected, but there's this close little tight double with a little bit of dark sky between 'em, could use some more magnification, but it is easily separated, the secondary is easily held with direct vision, no color noted, there's about a 8th magnitude field star clear on the other side of the field 10 arc-minutes distant, a nice interesting double; With the Celestron-8 using either 142X or 116X and the double centered in the FOV the star images are much more bloated compared to the 115 mm refractor, no dark sky between the components, the refractor gives a superior image I must say, anyway that's what I saw
Σ 2178           (Observed with AT115 EDT and Celestron-8)
7.1/9.1 magnitudes @ 10.6 arc-seconds; With the 115 refractor at 146X: yeah this little guy is nicely resolved, I can hold the secondary with direct vision, can't say a whole lot about color, perhaps the primary is a little yellowish but mostly just white, there's an 11 magnitude field star kind of opposite of the secondary's position angle, an interesting double, plenty of dark space between the components, good brightness contrast; With the Celestron-8 at 80X easily resolved, the secondary is more easily seen compared to the view with the 115mm refractor, perhaps the primary has got a little bit more of a yellowish color maybe even an orangish tint

 

That's all the Hercules double stars for now. When I get another batch of them I'll report what was seen.


Edited by Rustler46, 01 July 2018 - 12:49 AM.

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#2 MP173

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Posted 01 July 2018 - 10:24 AM

Rustler46:

Thanks for the detailed list of your obs.

 

You have provided a field guide for Hercules.  I am about 1/2 thru your list and made a list of stars to observe including several which I would have not looked for - STF 2068, 2087, and 2098 which are not even shown on iDSA as doubles.   

 

This is a really useful resource.  Thanks for sharing.

 

Ed



#3 fred1871

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Posted 01 July 2018 - 09:45 PM

IDSA is a very good deep sky atlas, but not directed toward double star observing. The CDSA 2nd ed is better for that, and a quick look through the doubles listed in it for Hercules gave me a head count of 67. Faint limit for CDSA2 is mag 7.75 (combined). For Haas's Doubles for Small Telescopes there's a similar cutoff by magnitude, and she lists 55 pairs in Hercules.

 

Some of the doubles Russ is listing won't be in the usual guides because he's gone for a number of pairs that are too dim for the cutoff point of the guides, whether CDSA 2 or Haas's. A guide that included all the pairs where the primary was as dim as magnitude 9 (Russ's dimmer pairs) would have too many doubles for a reasonably sized book unless it was a mere one-line listing for each: hence the cutoff by magnitude usually being around 7.5 or 8.0. The number of doubles increases very rapidly as magnitudes go fainter.

 

However part of the interest in Russ's list is creating awareness that even with a small scope (115mm) there are some doubles fainter than mag 8 that are interesting to observe. Only some, I'd say, given the modest aperture scope; that changes somewhat with larger scopes, as I've found in my observing of many of the 8th and sometimes 9th magnitude pairs with scopes in the 180mm to 235mm range. A lot more light can make a difference for some doubles, while others remain nondescript. 

 

A significant limitation to the notes is the observing in bright moonlight that's noted for various pairs; and with the dimmer ones the cutoff in visibility that causes. Better to go back on a Moonless night some time and find out if 115mm can show the fainter ones in easier conditions.



#4 mccarthymark

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Posted 02 July 2018 - 10:36 AM

Awesome report Russ!

 

Thanks for the reminder of BU 627; I had better luck with seeing when I observed it last August.  8/10 Pickering, 553x:

 

"BU 627: !! Very bright white star with a companion disk 2", 4-5 delta mag. Wow!  B illuminated by A as a planet might be by its sun. [A,BC seen. BC is an equal pair only 0.3" sep. -- maybe try in the 20-inch. 7 stars total in the system]"

 

I haven't followed up to try for BC yet but am inspired to do so now!



#5 OJS

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Posted 02 July 2018 - 06:28 PM

That's an impressive list. Seeing does indeed play a big role in trying to resolve Zeta Her. I had excellent seeing Sunday night and the companion to Zeta was either an obvious bulge on the 1st diffraction ring, and, when seeing was really steady, an obvious separate disc. 

This was in my 128mm refractor. Most times in my neck-of-the-woods (Ohio valley), Zeta goes unresolved. 



#6 Tropobob

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Posted 02 July 2018 - 06:43 PM

That's an impressive list. Seeing does indeed play a big role in trying to resolve Zeta Her. I had excellent seeing Sunday night and the companion to Zeta was either an obvious bulge on the 1st diffraction ring, and, when seeing was really steady, an obvious separate disc. 

This was in my 128mm refractor. Most times in my neck-of-the-woods (Ohio valley), Zeta goes unresolved. 

Agreed; its great to see reports like this. 

 

Regarding Zeta, I recently used my Tak100 (F7.4) at 148x, but could not resolve it. 



#7 MP173

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Posted 03 July 2018 - 07:28 AM

Russ:

Viewed Alpha Hercules last night and resolved it at 61x (20mm) but not at 48x (26mm).  Really stunning orange color for the primary.  I attempted to locate STF 2079 but didnt have iDSA with me for precise star hopping.  It should have been an easy resolve but it just couldnt be located.

 

I will be using your report as a "Field Guide of Hercules".  

 

Thanks again.



#8 OJS

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Posted 03 July 2018 - 01:20 PM

Agreed; its great to see reports like this. 

 

Regarding Zeta, I recently used my Tak100 (F7.4) at 148x, but could not resolve it. 

More power will be needed for this one; and excellent seeing. Good new is Zeta is widening....



#9 Rustler46

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Posted 03 July 2018 - 10:39 PM

IDSA is a very good deep sky atlas, but not directed toward double star observing. The CDSA 2nd ed is better for that, and a quick look through the doubles listed in it for Hercules gave me a head count of 67. Faint limit for CDSA2 is mag 7.75 (combined). For Haas's Doubles for Small Telescopes there's a similar cutoff by magnitude, and she lists 55 pairs in Hercules.

 

Some of the doubles Russ is listing won't be in the usual guides because he's gone for a number of pairs that are too dim for the cutoff point of the guides, whether CDSA 2 or Haas's. A guide that included all the pairs where the primary was as dim as magnitude 9 (Russ's dimmer pairs) would have too many doubles for a reasonably sized book unless it was a mere one-line listing for each: hence the cutoff by magnitude usually being around 7.5 or 8.0. The number of doubles increases very rapidly as magnitudes go fainter.

 

However part of the interest in Russ's list is creating awareness that even with a small scope (115mm) there are some doubles fainter than mag 8 that are interesting to observe. Only some, I'd say, given the modest aperture scope; that changes somewhat with larger scopes, as I've found in my observing of many of the 8th and sometimes 9th magnitude pairs with scopes in the 180mm to 235mm range. A lot more light can make a difference for some doubles, while others remain nondescript. 

 

A significant limitation to the notes is the observing in bright moonlight that's noted for various pairs; and with the dimmer ones the cutoff in visibility that causes. Better to go back on a Moonless night some time and find out if 115mm can show the fainter ones in easier conditions.

The lists I've assembled so far have just been those doubles listed in Burnham's Celestial Handbook that can also be located in SkySafari Pro. The 145 doubles in Hercules meeting that criteria shows that there are plenty of double stars for us to observe. Of course many of the doubles Robert Burnham included are only visible with larger telescopes under excellent seeing conditions. But I've included these difficult pairs for those who may have access to suitable equipment, but also just for consistency. And yes, this makes for a large list. Most of Burnham's doubles are listed in the Handbook as single line entries. Very few have a more extensive writeup in his descriptive paragraphs for that constellation

 

As for bright moonlit nights, sometimes I just need to make the best of whenever my maritime climate provides a clear night. Bright moon, wind, poor seeing etc. are just conditions to be endured. As I go through the lists, I decide "is this double bright enough and wide enough to be worth my time examining". For example only 42 of the first 74 doubles on the Hercules list were selected due to such an assessment. 

 

Next chance I get, there is still the other half of the Hercules double star list to sift through - some 70 more pairs. I must admit to making good use of SkySafari for wireless control my Losmandy G-11 mount. And yes, I unashamedly use its go-to function to locate the pairs I observe. After over 45 years of using star atlas and finder scope to locate objects, my old neck and back benefit from such assistance. I try to avoid going through the list too fast, enjoying the view my little refractor provides for each of the pairs. If the electronics should ever go up in smoke I still have the Telrad and Sky and Telescope's Pocket Star Atlas. Until that happens I'll continue with the convenience go-to provides as I have for the last 10 years.


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#10 Rustler46

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Posted 03 July 2018 - 10:59 PM

Agreed; its great to see reports like this. 

 

Regarding Zeta, I recently used my Tak100 (F7.4) at 148x, but could not resolve it. 

I looked through my observing records - an Excel spreadsheet with over 3300 entries. Therein was found just 3 times when Zeta Hercules was observed. One was last month with the little 115 refractor as noted in my original post (not resolved). The other two are as follows

 

  • June 29, 2010 - Celestron-11 @ 215X, 3.0/5.4 mag. @ 0.9"; very tight, unequal double star; at times I am able to see a dimmer disc in contact with the primary in the position angle it should be at; but it dances in and out of view; very difficult
  • September 14, 2017 - Celestron-8 @ 114X, a tight unequal double star, magnitudes 2.9 and 5.5 at 1.3 arc-sec. With the kind of poor seeing I have tonight I see the secondary pop out from right next to the primary once in a while. But it always pops out in the same position. So I'm pretty sure of being able to resolve this little guy. But it's a tight little one under the circumstances.

According to Stella Doppie the separation in 2010 was more like 1.1 arc-seconds. But this is definitely a challenging double most of the time.



#11 Rustler46

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Posted 04 July 2018 - 01:03 AM

Russ:

Viewed Alpha Hercules last night and resolved it at 61x (20mm) but not at 48x (26mm).  Really stunning orange color for the primary.  I attempted to locate STF 2079 but didnt have iDSA with me for precise star hopping.  It should have been an easy resolve but it just couldnt be located.

 

I will be using your report as a "Field Guide of Hercules".  

 

Thanks again.

I'm pleased that you have found my report be of use. It was never meant to be "best double stars in Hercules", but was just going through the doubles list provided by Burnhams Celestial Handbook. It amazes me how much research Robert Burnham had to do to assemble all those  lists. 


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