594 replies to this topic

[jrazz]

I also observed a couple of super tough doubles with the APM 34x80.

 

STF2390

18h 45m 49.83s +34° 31' 06.6" P.A. 155.00 sep 4.3 mag 7.37,8.56 Sp A7V dist. 357.14 pc (1164.99 l.y.)

This was really tough to split. Relatively dim and very tight for the APM. I've been spoiled by the BT and it's good to see these as a challenge!

 

I also looked at:

STF2441AB

19h 02m 41.26s +31° 23' 58.5" P.A. 263.00 sep 6.3 mag 7.85,9.78 Sp A3 dist. 147.06 pc (479.71 l.y.)

Which was easier to split but the secondary was REALLY dim. 

 

All in all, the APM did wonderfully. I need to remember that 5" is actually pretty tight.

[jrazz]

I wanted a more reasonable Cass Caper for this year.

 

The original one: https://www.cloudyni...4#entry12217694

Is great and all but you need a binocular telescope.

 

I wanted a real challenging 20x-40x list.

Well here it is.

 

10"-4" doubles less than mag 10 in the wonderful constellation of Cassiopeia

Attached Files

•  Cassiopeia Caper Light.skylist   6.39KB   19 downloads

Edited by jrazz, 23 September 2023 - 10:33 AM.

[Fiske]

Thank you, Jordan!

 

  

[Fiske]

I've been pondering an easier/quicker telescope setup for viewing doubles challenging for BTs, like STF 222 / 7 Trianguli described in this What Did You See post, and then I thought of mounting the TV-101 on the same iOptron bino-bracket used for the127XL.  (Also using the same dovetail plate.  )

 

 

I haven't tried it out on doubles yet, but the dry run alignment routine in my garage was a snap, so I am hopeful this will be the answer. The Orion CC8 Classical Cassegrain will resolve even closer doubles, of course, but it is a lot more work to set up. The TV-101 is a breeze.

 

We'll see how it goes. 

 

(The towel on the rolling light shield unit was quickly draped over the top last night when my neighbor fired up his Christmas lights and the local power company had to turn on Auxiliary Nuclear backup.)

Edited by Fiske, 19 November 2023 - 07:25 PM.

[Fiske]

Here is a pleasing 20x binocular double, easily located in Andromeda.

 

 

H 5 17 AB / Pi Andromedae
00h36m +33*34′
4.36/7.08 sep 36.22″ pa 174.5*
Distance: 549.18 / 568.31 Light Years
Spectral Type: B5V / A6V
Color Index: -0.16 blue-white / +0.687 yellow-white

 

Observed with the Oberwerk 20x70 EDU on Wednesday 15 November 2023, my notes describe it as a brilliant white primary with a tiny dot hovering by its side.

 

More information is included in the Pi Andromedae blog post on ExploreTheNightSky.com. 

 

 

[JoeFaz]

Fiske, you talk a little about the William Herschel discoverer code in your blog post. I thought "H" (sometimes "h" or "HJ") were all John Herschel. Is capital "H" William, and only lowercase "h" John (I swear I've seen the same pairs listed with "H" or "h" from different sources)? Or is it the two separate numbers that specifically distinguish William as the discoverer?

 

On a side note, this pair is on the AL's "Advanced" list, so I'll be checking it out the next decent night here (hopefully tonight if these clouds will finally go away...)

Edited by JoeFaz, 12 December 2023 - 11:39 AM.

[Fiske]

Fiske, you talk a little about the William Herschel discoverer code in your blog post. I thought "H" (sometimes "h" or "HJ") were all John Herschel. Is capital "H" William, and only lowercase "h" John (I swear I've seen the same pairs listed with "H" or "h" from different sources)? Or is it the two separate numbers that specifically distinguish William as the discoverer?

 

On a side note, this pair is on the AL's "Advanced" list, so I'll be checking it out the next decent night here (hopefully tonight if these clouds will finally go away...)

Good point, Joe. I believe H versus h is a thing. 

 

I'll look into that and add a comment on the post accordingly. Good luck with your Pi Andromedae observation. Please share it in this topic, whenever the clouds disburse. 

[Fiske]

Ha!

 

The lowercase "h" is an alternative to HJ (John Herschel). See double star maven Bruce MacEvoy's Double Star Astronomy Part 3: Double Star Datasets page -- note table in Historical Catalogs section.

 

Thanks Joe! 

Edited by Fiske, 12 December 2023 - 10:53 PM.

[JoeFaz]

Good luck with your Pi Andromedae observation. Please share it in this topic, whenever the clouds disburse. 

I observed H 5 17 AB last night along with a number of other pairs and NGC open clusters.

 

I found it particularly interesting in comparison to another pair I visited, HJ 2028 AB. The 7.1 magnitude companion appears sooo much fainter than the 7.1 magnitude primary in HJ 2028. While I obviously couldn't compare them "side by side" per se, and HJ 2028 is a good bit more separated, it was still an interesting illustration of the significance of Δmag to view them together in the same session. Your description is precisely how I saw it as well.

 

HJ 2028 AB (Cassiopeia)
01h16m +74°02′
7.1/7.9 sep 63″ pa 204°

I thought I might have detected some orange hue in the companion, but couldn't say so with confidence.

 

A couple other pairs I really enjoyed last night, also in mounted 20x80s:

 

STF 2840 AB (Cepheus)
21h52m +55°48′
5.6/6.4 sep 18″ pa 197°

Blue-white primary, beautifully standing on its own in a sparsely populated FOV.

 

STF 627 AB (Orion)
05h00m +03°37′
6.6/7.0 sep 21″ pa 260°

Attractive pair of similar magnitude blue-white stars.

Edited by JoeFaz, 13 December 2023 - 10:01 AM.

[Fiske]

I observed H 5 17 AB last night along with a number of other pairs and NGC open clusters.

 

I found it particularly interesting in comparison to another pair I visited, HJ 2028 AB. The 7.1 magnitude companion appears sooo much fainter than the 7.1 magnitude primary in HJ 2028. While I obviously couldn't compare them "side by side" per se, and HJ 2028 is a good bit more separated, it was still an interesting illustration of the significance of Δmag to view them together in the same session. Your description is precisely how I saw it as well.

 

HJ 2028 AB (Cassiopeia)
01h16m +74°02′
7.1/7.9 sep 63″ pa 204°

I thought I might have detected some orange hue in the companion, but couldn't say so with confidence.

 

A couple other pairs I really enjoyed last night, also in mounted 20x80s:

 

STF 2840 AB (Cepheus)
21h52m +55°48′
5.6/6.4 sep 18″ pa 197°

Blue-white primary, beautifully standing on its own in a sparsely populated FOV.

 

STF 627 AB (Orion)
05h00m +03°37′
6.6/7.0 sep 21″ pa 260°

Attractive pair of similar magnitude blue-white stars.

I fine report, Joe. Well done! 

 

And thank you for sharing. 

 

I'm looking forward to making the comparison between Pi Andromedae and HJ 2028 now. I have no record of observing it in my journals. And STF 627 looks extremely promising. Another double I have not previously viewed, but looks to become a favorite.

 

STF 2840 is a favorite that I view whenever I am roaming in Cepheus. An observation of it is included in this report from September 2021.

 

The contrast effects between pairs of stars influence our visual perception to a remarkable extent.

Edited by Fiske, 13 December 2023 - 09:53 PM.

[columbidae]

Last time I was out, I decided to find an area with a clear southern horizon and do what straight-through binoculars do best - horizon diving.

 

DUN 5 (Eridanus)

 

01h59m -56°11′
5.8/5.9 sep 11.3″ pa 186°

 

I was out looking for Achernar (Alpha Eri), which culminates a few degrees above my horizon and decided to check my charts for a nearby double and found this - a bright, close, and even double near the end of the river.  It's a pair of K-class stars about 25 lightyears away (nearby, similar to Vega) with a period of 500 years ranging from 2.5" to around 11" separation where it lies now - a nice close split for 20x's.  Though both the color and split were more difficult to pick out that close to the ground. 

 

Once it's well placed, I'm hoping to add Alpha Centauri to my list of horizon-scraping doubles.

[Fiske]

A worthy pursuit, Columbidae! 

[Dale Smith]

+1 on Fiske’s comments, Columbidae! I’d do that if I had a flat horizon here, but I don’t 

[JoeFaz]

Last night was mostly a DSO observing session with my 20x80s, but I did stop by several doubles as well. Here are two of the highlights:

 

STF 307 AB (Eta Persei)
02h50m +55°54′

3.8/8.5 sep 29″ pa 301°

Brilliant and beautiful yellow-gold primary nearly overpowers its very faint blue companion.

 

S 397 (35 Cassiopeia)

01h21m +64°39′

6.3/8.6 sep 57″ pa 342°

Wide pairing of white primary and deep orange secondary. Very attractive color contrast. It appears that Fiske already reported on this way back in this topic, but I am including it again because I found it a particularly appealing pair.

 

I think I'm finding the AL's "advanced" double star program even more enjoyable than the regular one!

Edited by JoeFaz, 15 December 2023 - 12:21 PM.

[Fiske]

Last night was mostly a DSO observing session with my 20x80s, but I did stop by several doubles as well. Here are two of the highlights:

 

STF 307 AB (Eta Persei)
02h50m +55°54′

3.8/8.5 sep 29″ pa 301°

Brilliant and beautiful yellow-gold primary nearly overpowers its very faint blue companion.

 

S 397 (35 Cassiopeia)

01h21m +64°39′

6.3/8.6 sep 57″ pa 342°

Wide pairing of white primary and deep orange secondary. Very attractive color contrast. It appears that Fiske already reported on this way back in this topic, but I am including it again because I found it a particularly appealing pair.

 

I think I'm finding the AL's "advanced" double star program even more enjoyable than the regular one!

Another fine report, Joe. Thank you for sharing! 

 

A part of the fun with binocular double stars is comparing notes with other observers, not to mention looking back over one's own logs and comparing observations with different binoculars, with telescopes, and etc. Eta Persei is in the Astronomical League's Double Star program. I observed it working on that program on Tuesday 6 November 2001. 

 

 

Tuesday 11/6/2001
12:11 am
KC Metro Area
G9.25 / 22mm Nagler T4
 

One of my favorite doubles! Color contrast is striking -- deep yellow and distinct lavender/blue. Faint stars can be made out nearby in averted vision. These would be much easier on a moonless night. 

 

Here is an observation of S 397 made in October 2022.

 

 

S 397 / 35 Cas
01h21m +64*39'
6.34/8.63 57.4" pa 342*

 

Maven 12x56: Bright white primary with blood orange secondary, generously spaced and part of a beautiful triangular asterism of 6th magnitude stars. Also readily seen with 10x56. And I kept stumbling across more doubles. 

Edited by Fiske, 15 December 2023 - 01:52 PM.

[JoeFaz]

A couple good ones I observed last night along with my notes:

 

STF 3053 - Cassiopeia

00h02m +66°06'

6.0/7.2 sep 15" pa 70°

Primary is yellow-white, secondary is blue. Very visually appealing pair!

 

S 476 ABC - Lepus

05h19m -18°31'

6.3/6.5/9.5 sep 39"/167" pa 18°/21°

I stumbled on this on serendipitously on the way to M79. Beautiful pair of similar magnitude stars. Primary is blue-white and secondary is white, maybe slightly yellow-white. There is a very very faint star at a similar position angle as the secondary, but with about 3 times the separation from the primary that may or may not be related. --- After some research, it was the magnitude 9.5 "C" component I saw. AB are physical, and C is optical.

 

I found S 476 the first time I was attempting to look at M79. It turned out that M79 was still just below the treeline, so I came back to it later. That next time, I unexpectedly came across NGC 2017 which was the highlight of the evening. I reported on that observation here, but mention it here as it is a wonderful target for anyone interested in observing double/multiples with binoculars. After some investigating once I came inside, its official status over the years has shifted between open cluster, multiple star, and I believe it's settled now as a chance asterism. In fact, it is listed in the WDS as HJ 3780. In any case it's beautiful in 20x80s and one of my new favorite binocular objects. It's a shame the AL didn't include it in their "Binocular Deep Sky" program.

[Fiske]

Another fine report, Joe! 

 

I finally got my follow up observation of HJ 2028 published, in this ExploreTheNightSky blog post. It's a lot of fun, and a fantastic comparison with Pi Andromedae, as you point out. The post includes a map showing the position of HJ 2028, and another nearby (and similar) double that is just to the west of the 23/21 Cassiopeiae pair.

 

STTA 1
00h14m +76*01′
7.19/7.69 sep 73.69″ pa 103*
Optical / Non-physical
Distance: 1089.33 / 1392.22 light years
Spectral Type: M4III / G5
Color Index: +1.63 orange-red / +1.05 orange

 

In addition, a few evenings ago (before clouds and now snow(!) arrived), I did a front porch observing session and viewed STF 627 in Orion, which is now another favorite binocular double. Thank you for sharing that! 

 

A blog post with details to follow. 

Edited by Fiske, 05 January 2024 - 05:57 PM.

[Fiske]

It was clear Wednesday evening (3 January 2024) so I did some front porch astronomy with the Kowa Highlander, the OB 20x70 EDU, and a few of the Maven b5 tribe.

 

 

I observed STF 627, with a range of instruments. It is easily located triangulating off the Pi 5 and 6 stars at the bottom of Orion's shield. It can be resolved with mounted 10x binoculars, and the Canon 10x42L hand held, but it's more enjoyable to me with additional magnification. Even 12x makes a difference. It's very nice at 15 or 20x, and gorgeous at 32x (Kowa Highlander).

 

STF 627
05h00m +03*37'
6.6/7.0 sep 20" pa 260*

 

My notes describe it as a blue white primary with a white secondary at a cozy distance. The primary is slightly brighter.

 

The remarkable carbon star, W Orionis, is nearby, and a gorgeous bright copper in all binoculars.

 

Studying Sky Safari I realized that a second Struve double is adjacent to 627.

 

STF 628
05h00m +03*16'
8.13/9.85 sep 22.8" pa 47.7*

 

I was unable to resolve STF 628 with the Kowa at 32x. I expect it would be observable with the 100XL-SD with a bit more magnification. Or possibly for a support telescope, like the newly revived AT-80 Little Jon refractor.  Alas, the Baader Amici diagonal arrived two days too late, and now it's overcast and snowing. 

Edited by Fiske, 06 January 2024 - 12:17 AM.

[Fiske]

Here is a closer view of STF 627 and 628. It's a charming starfield. I'm looking forward to clear skies (and no snow on the ground  ) to revisit with the 100XL-SD and a support telescope or two. 

 

[aznuge]

I took a tour of double stars last night with a combination of two binoculars and a BT.  There were six targets, one in Lacerta (8 Lac) and 5 in Orion (Struve 747, Delta Ori, Theta 2 Ori, Theta 1 Ori, and Iota Ori). Instruments I used were the Orion 2x54 wide-field Galileans, the Nikon 18x70 Astroluxe and the Oberwerk BT100 SD, with Nikon Nav-7mm SW eyepieces.  The ones that stood out to me were 8 Lac and the fun combo of 2x and 18x to find and observe this distinctive double star; and Iota Orionis STF 752 AB (Hatysa), as seen through the BT at 80x was fun.  The high delta magnitude of this double made it a delight with the usual (for me) routine of "where is it, I can't see it, I should be able at this power with good seeing, BOOM, there it is!"  Majestic to see those subtle companions glimmer palely in the bright "shadow" of their senior companion in magnitude.  Another in the same category last night was Mintaka and its companion (Delta Orionis, STFA 14 AC).

 

Also of note to me is the described orientation of Theta 1 Orionis (trapezium) STF 748 AB, AC, AD.  According to Stelle Doppie the relationship of these stars is either unknown or NOT physical.  The brightest of these is Theta 1 Orionis C, yet the PA designations of these four key off of Theta Orionis A.

[JoeFaz]

I had a fun and productive night of double star observing last night. I split two sub 10" pairs with my 20x80s, my closest to date with binoculars. The most challenging pair of the night was actually 10.5" STF 688 though, requiring a good deal of concentration on patience for a clean split. H 5 65 ABCD was a nice multiple as well, with the "C" and "D" components on the very fringes of detectability.

 

I've been a little down on my 20x80s as I've begun acquiring some other binos that are definitely of a higher quality. Certainly they are a "budget" instrument and optically aren't anything to write home about, but I've managed to split sub 10" doubles with them, reached just into 10th magnitude (10.18 - M40/WNC 4), and observed some moderately challenging DSOs to boot, so I think maybe I need to cut them a little slack!

 

H N 19 - Puppis

07h34m -23°28'

5.8/5.9 sep 9.9" pa 118°

 

H 3 27 AB - Puppis

07h38m -26°48'

4.4/4.6 sep 9.9" pa 318°

 

 

STF 688 - Orion

05h19m -10°45'

7.5/7.6 sep 10.5" pa 95°

 

H 5 65 ABCD - Canis Major

06h55m -20°24'

5.8/8.7/9.2/9.7 sep 42.9"/48.5"/128.8" pa 147°/187°/187°

Edited by JoeFaz, 15 February 2024 - 03:28 PM.

[Dale Smith]

Great session report, JoeFaz! You’re inspiring me to try these if/when the clouds part here 

[Takuan]

The other night, looking for the Galaxy C7 with the BT-70 at 57x, I came across this double (triple, in fact) that I liked. Three pin point stars very close together in a very nice image. The weakest member was a little dull, so with a 100 mm BT or telescope, the trio is more aesthetically pleasing.

HD 62196 Camelopardalis
7h 49' / 63⁰59'

In the image the limiting magnitude is 11
(Image from Stellarium app.).

Attached Thumbnails

• 

Edited by Takuan, 17 February 2024 - 02:19 AM.

[JoeFaz]

The other night, looking for the Galaxy C7 with the BT-70 at 57x, I came across this double (triple, in fact) that I liked. Three pin point stars very close together in a very nice image. The weakest member was a little dull, so with a 100 mm BT or telescope, the trio is more aesthetically pleasing.

HD 62196 Camelopardalis
7h 49' / 63⁰59'

In the image the limiting magnitude is 11
(Image from Stellarium app.).

Looks like you stumbled across STF 1127 ABC, in case you wanted the designation for your record keeping!

 

I would need one of my scopes for the AB split, too close for a meager 20x80 (5.6").

[Takuan]

Looks like you stumbled across STF 1127 ABC, in case you wanted the designation for your record keeping!

I would need one of my scopes for the AB split, too close for a meager 20x80 (5.6").

Thank you so much. I hope you can tell me with what telescope and magnification you see it.