601 replies to this topic

[Fiske]

I tried finding STF 817 last night with my Pentax 20x60 SP WP but the area immediately south of Betelgeuse was pretty sparse here. My SQM showed 18.77 MPAS and my back yard was protected from local lighting. Of course, the Pentax’s FOV is narrower by half at 2.2 to the 20x70 EDU. It’s also possible that was just off where I looked, too. I went south, and then north, and perhaps at 2.2 degrees I didn’t go south quite far enough.

STF 817 is annotated HD 39758 in this chart. It's close to Betelgeuse. The FOV circle is 2 degrees, so close to that of the Pentax 20x60 SP.

 

Edited by Fiske, 10 March 2024 - 11:05 PM.

[Fiske]

Here are some Orion 50 observations from last night (Saturday 9 March 2024).

 

I was observing with the Oberwerk 70XL and Explore Scientific 24mm eyepieces (16.25x / 4.2* FOV), which is a remarkably capable observing combo. 

 

STTA 73
06h19m +13*26'
6.94/7.74 sep 72.3" pa 44.2*
Spectral Type: F6V / K1V (yellow-white / yellow-orange)

 

Bright white primary with orange secondary at a comfortable distance. Primary a little brighter. A brilliant field.

 

AG 321

06h 05m +14*35'
7.78/8.84 sep 35.78" pa 188.6*

 

 

In a quadrilateral of stars near Nu Orionis. Bright white primary with white secondary at a cozy distance. Primary brighter. A delicately fine double in an elegant field.

 

S 502

05h54m +13*51'
7.89/8.29 sep 46.02" pa 131.5*

 

 

Both stars white. Comfortable distance. Primary slightly brighter. In a complex and attractive asterism.

 

STF 840

06h06m +10*45'
7.17/8.95 sep 21.52" pa 248*

 

Bright white primary with shy tan companion nestled just below. The center of a cross asterism. Charming.

 

STF 853

06h09m +11*39'
8.49/8.98 sep 38.167" pa 7.8*

 

At the opposite end of a stream of faint stars starting at STF 840. Yellowish primary with white secondary. Cozy distance. Primary slightly brighter. Interesting. According to simbad, the primary is white and the secondary yellow. 8.42 visual mag versus 8.87. Will revisit. What I identified as the primary seemed like the brighter star of the pair.

[Dale Smith]

STF 817 is annotated HD 39758 in this chart. It's close to Betelgeuse. The FOV circle is 2 degrees, so close to that of the Pentax 20x60 SP.

 

Thanks, Fiske! This is very helpful. I’ll give it a try, hopefully in a few days—we’re forecast to have several clear nights in a row starting on Thursday or Friday. Fingers crossed.

[columbidae]

Took my 20x70's out against the "Orion 50 Challenge" list in my backyard tonight (roughly Bortle 6-7).

 

Managed to observe 21 out of the 50 pairs, with the minimum magnitude secondary being 9.49 in STF 798 and the minimum separation being 8.5" in STF 761 BC.  (Honorable mention goes to STF 953 in neighboring Monoceros with a clean split at 7.7" and Lambda Ori STF 738 AB with an uncertain notch at 4.1")

 

After about halfway through the list I stopped trying for any pair with a 10.5 magnitude secondary or dimmer, but it's pretty fair to say that darker skies and/or bigger guns are needed to get some of the ones on this list.  With relaxed separation criteria I could probably catch dimmer secondaries than 9.5, but not at <25".

 

Pretty fun jaunt through Orion otherwise - thanks for the list!

Edited by columbidae, 13 March 2024 - 12:13 AM.

[jrazz]

Wonderful report!
I should have limited the secondaries to less than 10. Some of these are tough from a suburban back yard.

I’m really glad you enjoyed it though! I was surprised at just how much Orion had to offer beyond Betelgeuse and M42

[jrazz]

Wow! Incredible night tonight!!!

I had both the Tak FC-100DC and the BT-100XL/SD out. Super super steady seeing with incredible transparency. I've NEVER seen it this good around here. Kinda makes you jealous of those with steady skies.

 

Boring but beautiful

 

Some incredible doubles, triples and systems tonight. Most at 93x (TPL 6mm). Some at 140x (TOE 4mm) and some at 296x on the telescope for verification. All were observed and split with the BT. No doubt it's harder but I made it a point to show that it can keep up!

 

First up:

STT 179 (Kap Gem)

07h 44m 26.87s +24° 23' 53.3" P.A. 243.00 sep 7.0 mag 3.66,10.00 Sp G8IIIa dist. 43.35 pc (141.41 l.y.)

Sort of an interesting double. Very suited for BT observation where the magnitude difference isn't such an impediment. Good solid start. I like!

 

HU 614 (UV Aur)

05h 21m 48.92s +32° 30' 39.8" P.A. 5.00 sep 3.5 mag 9.20,11.00 Sp CII\

Really dim. Especially the secondary. This took a while to pick up.

 

STT 103 (16 Aur)

05h 18m 10.56s +33° 22' 17.8" P.A. 55.00 sep 4.1 mag 4.80,10.60 Sp K3.5III dist. 71.23 pc (232.35 l.y.)

Very challenging. Really close and a significant difference in magnitude. This one was observed in the BT but I needed the telescope at 300x to confirm. 

 

STF 948 AB (12 Lyn)

06h 46m 14.15s +59° 26' 30.1" P.A. 65.00 sep 1.9 mag 5.44,6.00 Sp A3V+A1IV dist. 65.83 pc (214.74 l.y.)

with

STF 948 AC

06h 46m 14.15s +59° 26' 30.1" P.A. 309.00 sep 8.9 mag 5.44,7.05 Sp A3V+G5IV dist. 65.83 pc (214.74 l.y.)

WOW WOW triple WOW!!!

Totally worth it for such a close double. Totally doable at 140x as well. The AB pair are big and bright and were easy to separate. The "C" star was off to the side looking dimmer. Such a rewarding system! Must do for you BT double fanatics

 

STF 262 AB (Iot Cas)

02h 29m 03.96s +67° 24' 08.7" P.A. 231.00 sep 3.0 mag 4.66,6.92 Sp A4V+F5V dist. 40.73 pc (132.86 l.y.)

Oh, I'm sorry. You thought 12 Lyn was incredible? 

Wow, you have no idea! One of the most incredible system I've seen. Big beautiful primary surrounded by 3 gorgeous stars all with different colors. Seriously, made my night. SkySafari has a picture that honestly doesn't do it justice. I could see all the components much more easily than that. Awesome, simply awesome!

 

So, couple of nice solid doubles. Seriously cool systems. Let's try something that I haven't succeeded in before:

STF 774 AB (Alnitak - Zeta Orionis)

05h 40m 45.52s -01° 56' 33.3" P.A. 166.00 sep 2.4 mag 1.88,3.70 Sp +B0III dist. 225.73 pc (736.33 l.y.)

I think I saved the best for last. So cool! At 140x I could clearly separate two dots of bright light. However, here is where the telescope pulls away. At 300x two beautiful orbs right next to each other. My seeing NEVER supported splitting Alnitak before. I'm so stoked to see it!

 

Wow, what a fun night!

Yes, I also split Rigel (easy) and Sirius (less easy) and the Trapezium E and F just as a regular thing. Once you know what to look for these become second nature.

 

Fun fun fun night!

[aznuge]

Alnitak is definitely a milestone double for BTs

[Fiske]

Congratulations on a night of fantastic viewing conditions, Jordan, and thank you for sharing your observations of these challenging double stars. 

 

  

 

A few of these might be doable under my doubtful urban skies.  Though I probably won't attempt them without a companion telescope backing up my trusty 100XL-SD. 

[jcj380]

If not mentioned already, this can be a helpful site:

 

http://www.virtualco...tar_search.html

 

Configure your search and...  Bazinga!

Edited by jcj380, 19 March 2024 - 09:03 AM.

[Bill Barlow]

Glad you were able to get out and observe last night Jordan when you had great skies.  I’ve seen some of the double star groups you observed but Iota Cass is one of my favorite triple star systems to see.  Even here in light pollution land I can usually split and see all three members.

 

Bill

[jrazz]

Glad you were able to get out and observe last night Jordan when you had great skies.  I’ve seen some of the double star groups you observed but Iota Cass is one of my favorite triple star systems to see.  Even here in light pollution land I can usually split and see all three members.

 

Bill

Why do I have a vision of Patrick Stewart yelling "there are 4 stars!"

 

The system has 4

[Bill Barlow]

Where is the fourth one then?  Is it way way far away from the other three ?  I’ve never seen it listed as a four star system.

Edited by Bill Barlow, 20 March 2024 - 10:01 AM.

[jrazz]

Where is the fourth one then?  Is it way way far away from the other three ?  I’ve never seen it listed as a four star system.

If you look at the Stelledoppie link (https://www.stelledo...p?iddoppia=8990) you see that there are 4 stars to STF262 - A, B, C, D. (ok, fine, "C" is also a double by itself - Ca and Cb but that's 0.2" separation - I digress)

 

AB are only separated by 3" so it's hard to see without some serious magnification and steady skies. 

 

 

Heck, even Wikipedia calls it a "quintuple" system: https://en.wikipedia...ota_Cassiopeiae

 

Huh...

 

I guess there are 5 stars (thinking of the Patrick Stewart STNG skit )

Edited by jrazz, 20 March 2024 - 10:24 AM.

[jrazz]

Wait a minute... Looking back at the SD site, AD is separated by 210"... I guess what I saw is the separation of Aa and Ab. That's 0.6"

 

I definitely saw the elongation which just goes to show what kind of insane night that was

 

Sorry for the confusion - I honestly saw all 4 stars and assumed the "C" component was "D" and that the "D" was just a rando.

 

 

That is sooo cool!!

 

I will definitely revisit this system with the TOA!

Edited by jrazz, 20 March 2024 - 10:33 AM.

[jcj380]

17 Cygni is nice if you want something different from Albireo while wandering along the spine of the swan.  I ran across it while hopping my way to Chi Cygni this morning (although I confess I was using my ST80, not binos   ).

 

Separation is listed as 26", so it should be relatively easy.

[Bill Barlow]

Sky and Telescope also lists Iota Cass as a triple star system.  I can see a few other stars near this triple star system, mostly to the east, so one of those is gravitationally bound to the other three?  Okay, I guess from Stelledoppie the separation is so small I'll never see it anyway.

 

Bill

Edited by Bill Barlow, 20 March 2024 - 03:52 PM.

[JoeFaz]

Only AB are physical, the C and D components are just optical.

[Fiske]

The skies and my schedule have not been playing nice with each other over the past month or so, still I have managed forays into Camelopardalis and Lynx, and have just published an ExploreTheNightSky blog post covering the Camelopardalis adventure, with a not-to-be-missed feature image. 

 

Here is a fine double for hand held binoculars, one of eight included in the post. 

 

STFA 13 / 11 and 12 Camelopardalis
05h06m +58*58′
5.20/6.21 sep 177.7″ pa 9.5*
Distance: 686 LY / 705 LY
Spectral Type: B3Ve / K0IIIe
Color Index: -0.12 blue-white / +1.13 orange

 

Easily resolved with hand held binoculars, even lower magnification. Fine colors of light blue and deep yellow.

[Takuan]

In recent days, the last visit to a dark site wandered restlessly through my mind. It was a wonderful night of galaxy hopping in which, by chance, I came across a pair of double stars that I thought were very beautiful. That night I used the dob/bv with a pair of UFF 18s, resulting in 69x.

Since I didn't have time to wait for the mirror to cool down, I took out the BT-70 with a pair of TS Optics 7mm Planetary HR (57x/ 1º).

The stars were: (according to S. Safari)
HD 112278 (6.96/ 9.13- 29.2") and HD 115404 (6.55/ 9.5- 7.8"). In Virgo and Coma Berenices.

Well, although I expected it, they disappointed me a little. Easily resolved (logically), but the secondaries appeared too weak and the saturation of the colors was lacking (even in the primaries).
Indeed, there are doubles that are only seen in their maximum splendor with a minimum of aperture.

Out of curiosity I put a 70mm mask on my ST-90 and matched the amplification with an ES 8.8mm. The result was pretty similar, although the telescope (at f7.1) still showed enough CA to make the experience less enjoyable than with the BT. Although, everything must be said, the bright stars were a little more pin point in the ST than in the BT.

Observed: Castor, Polaris, Porrima, Mizar, HD 78767, HD 105421 and a short look at Izar (not resolved at 57x, but at 100x in the ST).

Edited by Takuan, 04 May 2024 - 04:40 AM.

[JoeFaz]

I woke up early this morning and I brought my 15x70s out with my 6" dob. The session's main purpose was to gather up the last 4 Messiers with my telescope to finish all 110 (which I did!). Afterward I switched to the 15x70s and observed a bunch of summer Messiers. While observing M11 (one of my very favorite open clusters, but really too small for 15x) I noticed this great binocular double star that I thought was very much worth sharing here:

 

H 6 50 AC (Scutum)
18h50m -05°55′
6.2/8.2 sep 112″ pa 171°

Immediately NW of M11, primary is orange and secondary is blue-white. Fairly wide, but not so much so to detract from its appeal. A very fine binocular pair. There is a much fainter (mag 12.5) "B" component closer to the primary that is too faint for a 15x70 binocular.

Edited by JoeFaz, 13 May 2024 - 09:28 AM.

[jrazz]

I looked it up on SkySafari and it looks beautiful! 

 

I will have to try and find it with the 15x50... Being next to M11 is just a bonus.

[Fiske]

After my Celestron 6SE refresher course last Friday evening (24 May 2024), I settled down with the 100XL-SD (fitted with Pentax 20XWs -- 28x/2.5* FOV), the Canon 15x50 IS, and the AT80ED support telescope for some Little Dipper doubles. Most of these aren't actually in the Little Dipper, but they are at least nearby and easily located from it.

 

STF 1972 / Pi1 UMi
15h29m +80*27'
6.64/7.30 sep 31.63" 78.9*
Physical double star
Distance: 71.27 LY
Spectral type: G1.5V/G9V
Color Index: +0.64 yellow / +0.80 yellow-orange

 

100XL-SD+20XWs – Warm white primary with white secondary at a friendly distance. Primary brighter. Forms a neat equilateral triangle with two bright field stars. In a nice field. Easily viewed with the Canon 15x50 IS.

 

STF 2241 / 31 (Ps1) Draconis / Dziban
17h41m +72*09'
4.60/5.59 sep 29.6" pa 14*
Physical double star
Distance: 74.5 LY
Spectral type: F5IV / F8V
Color index: +0.43 yellow-white / +0.51 yellow-white

 

Splendid with the Canon 15x50. Really a great double for it. Yellow primary with a blue-white secondary. (Sky Safari has the color as yellow and lilac, which is charming.) Colors more pronounced with the 100XL-SD+20XWs but still discernible with the 15x50. Could actually resolve it with the Maven b.2 7x45 handheld. In a fine star field.

 

STF 2452
18h53m +75*47'
6.73/7.35 sep 5.669" pa 217.1*

 

Forms a wide triangle with Dziban and 41 Draconis. Just resolved with the 100XL at 28x. Nicely seen with the AT80ED at 80x (7mm Nagler Type 6). Both stars white. Primary slightly brighter. The carbon star UX Draconis is not far from STF 2452. I over looked it Friday evening (24 May 2024) and have added it to my To-Observe List for a return visit soon.

 

STF 2308 / 41 Draconis
18h00m +80*00'
5.70/6.0 sep 18.77" pa 231.8*

 

A double star of legend. Yellow primary with white secondary, both stars brilliant. Splendid with the 100XL-SD+20XWs. Nicely resolved with the Canon 15x50.

 

STF 1694
12h49m +83*25'
5.29/5.74 sep 21.8" pa 324.1*

 

Another fine double with the 15x50 IS. Two brilliant white stars. With the 100XL at 28x the primary has a slightly warmer color tone. It's also slightly brighter. In Camelopardalis.

 

STF 1625
12h16m +80*08'
7.24/7.78 sep 14.496" pa 216.8*

 

Just resolved with the 15x50 IS. A pleasing companion double to STF 1694 with the 100XL. Also in Camelopardalis.

 

I noticed this support telescope challenge double in Ursa Minor later, when reviewing my observations, and plan a return visit with the 120 EON and also the 6SE. (After I have collimated it!)

 

STF 2034
15h48m +83*37'
7.68/7.95 sep 1.078" pa 109.7*

 

And also this Nuge-special double in Draconis, one of the closest double stars to our solar system. It should be a fine subject for the 120XL with Orion 24mm UFF eyepieces (28x). I'm not sure the red color of the components will be detectable, however, given how faint they are.

 

STF 2398 / Gliese 725
18h42m +59*38'
9.11/9.96 sep 11.4" pa 180.8*
Physical double star
Distance: 11.65 LY
Spectral Type M3V/M3.5

Edited by Fiske, 27 May 2024 - 07:24 PM.

[jrazz]

I think I know what I'm looking at tonight!

[Fiske]

I think I know what I'm looking at tonight!

  

[jrazz]

Wonderful wonderful suggestions Fiske!

I managed to see all of these and more using the Tak FC-100DC and the Canon 15x50IS (CIS).

 

What struck me most of all was just how colorful the doubles appeared when compared to the Tak. I would have expected the opposite but doubles like Dziban, which I do think is yellow and Lilac, were gorgeous compared to the Tak. I should have dragged out the BT but was lazy!

 

On the other side of the sky (not quite but South rather than North) I found some nice doubles and a hat! (Sombrero)

 

Right next to the hat you can find three really pretty doubles:

STF 1664 AB (HD 109875)

12h 38m 19.95s -11° 31' 01.1" P.A. 223.00 sep 38.7 mag 7.82,9.17 Sp K0 dist. 917.43 pc (2992.66 l.y.)

 

STF 1664 EF

12h 38m 27.65s -11° 31' 42.4" P.A. 112.00 sep 92.7 mag 8.58,8.91 Sp G5

 

And the much dimmer but still pretty

STF 1664 CD

12h 38m 16.60s -11° 30' 24.4" P.A. 258.00 sep 30.0 mag 11.52,12.43 Sp K0

 

So a sextuple system! Wow!

It really looks like a miniature UMi. CD do require good seeing and darkness but from a Bortle 5 and down should be doable in a 80mm BT. I only saw AB/EF in the CIS. CD was detectable in the Tak.

 

Right nearby I stumbled on an absolute gorgeous double!

STF 1669 AB (58 Crv / vv Corvi)

12h 41m 16.22s -13° 00' 53.6" P.A. 314.00 sep 5.3 mag 5.88,5.89 Sp F5V+F5V dist. 78.93 pc (257.47 l.y.)

I could not really split it with the CIS. This would be at the limit for the 34x80 but the 100mm had no problem showing two sharp, intense white stars.

 

 

Going back towards UMi I found a couple of other fun doubles for BTs:

STF 1846 AB (Elgafar)

14h 28m 12.22s -02° 13' 40.6" P.A. 111.00 sep 5.2 mag 4.92,10.02 Sp G2III dist. 36.26 pc (118.28 l.y.)

Yeah, pretty tough but when the sky is good (like it was tonight) you can see some pretty interesting doubles. This one is for the bigger BTs and/or support telescopes but it is rewarding!

 

I finished with a wonderful double for the 15x CIS!

STF 1692 AB (Cor Caroli)

12h 56m 01.67s +38° 19' 06.2" P.A. 230.00 sep 19.3 mag 2.85,5.52 Sp A0pSiEuHg dist. 35.2 pc (114.82 l.y.)

What a pretty white/yellow double! Perfect for the CIS!

 

I love doubles!