601 replies to this topic

[jrazz]

You know... I'm willing to bet it won't.

If my Orion 10" dob wasn't able to I don't think this can but I'm hopeful!

 

I think you do, however, have a couple of better tools (ahemm 127) in your collection (hmm 22")....

[Fiske]

If there really is a 1.6" double with component magnitudes of 7.30/7.40 there, it won't be difficult for that CC8. The only limiting thing would be atmospheric conditions. The resolution of that Cassegrain is considerably higher than what a mass-market 10-inch Dob is capable of resolving. It should be able to resolve sub-arcsecond doubles given steady seeing.

Edited by Fiske, 13 January 2023 - 10:37 AM.

[Fiske]

The 127XL wouldn't even come close. It doesn't support high enough magnification, and binocular optical paths are complex for high magnification views. It might be possible with a top end bino-scope like what Tammy owns, but it's so much work even for an instrument of that quality, that telescopic observation is preferable. At least from my perspective. 

Edited by Fiske, 13 January 2023 - 10:52 AM.

[jrazz]

That's interesting.... I find my 100 our resolves the 10" any day. 

I might have to scour the classifieds for a 10" SCT then - purely for science of course!

[Fiske]

Here is a CloudyNights user review of the GSO 8" True Cassegrain. The Orion CC8 is made by GSO.

[Fiske]

That's interesting.... I find my 100 our resolves the 10" any day. 

I might have to scour the classifieds for a 10" SCT then - purely for science of course!

Of course! 

[scroff]

I came across a pleasing double star last night viewed through mounted 10x50 binoculars. I had been panning the sky in Canis Major and Orion, then decided to take a look at Lepus. I wanted to give that constellation a little bit of attention. There, I came across the double star consisting of TX and YZ Lep (while observing, I had no idea of their designations). It was easy to spot if one takes a line from Arneb to mu-Lep, and from its half-way point, take a perpendicular (horizon-side) roughly one-third the length of the first line and it's there. The stars are fairly close in brightness and did not have a color that stood out, so similar color and close enough to white for me not to tell. It stood out nicely in the binocular field of view. A nice target with low neck strain!

[clastro8*]

I'm looking forward to seeing that one, it's noted as S476 in my atlas.

 

Recently I visited gamma Lepus, it's pretty much on a straight line from Rigel Orion through Arneb to gamma, a distance total of about 16 degrees.  If you want to start at Arneb, there is a nice triangle consisting of Arneb, beta, and gamma, with beta further from Canis Major than gamma.  I think all 3 will fit into a 6-degree fov.  The numbers are 3.6/6.3 mag, 96" sep, and 350* PA.

[jrazz]

Soooo I looked at 

OCC 253

03h49m +24*23'

Aa/Ab 7.30/7.40 1.6" pa ??

 

Again...

 

Yesterday, after wheeling the 34x80 in I went to make/eat dinner and deal with the household pests personalities. Post that and an enthusiastic post on "What did you see last night in your binoculars..." I took out the BT-100 and did some doubles.

 

To begin with, went back to the beautiful

STF 616AB (Ome Aur)

04h 59m 15.41s +37° 53' 24.9" P.A. 5.00 sep 4.7 mag 5.00,8.21 Sp A1V dist. 52.27 pc (170.5 l.y.) 

 

Which was bright and really easy to split @56x. The BT-100 really shows it's strengths with mismatched doubles as there is very little glare.

 

I then went to look at a more challenging double:

STF 262AB (Iot Cas)

02h 29m 03.96s +67° 24' 08.7" P.A. 228.00 sep 3.0 mag 4.63,6.92 Sp A5pSr dist. 40.73 pc (132.86 l.y.)

Which was surprisingly easy to separate as well. Just shows the conditions.

 

Then I finally looked at 

OCC 253

03h49m +24*23'

Aa/Ab 7.30/7.40 1.6" pa ??

 

Really still, winter air. Transparent. Good conditions. Capable instrument aand no. Again, I could be convinced there is something there but I could not clearly separate a double nor even clearly see the elongation. I tried to wheel out the telescope but even at 240x I could not see anything realistically.

 

Sorry.

[Fiske]

I came across a pleasing double star last night viewed through mounted 10x50 binoculars. I had been panning the sky in Canis Major and Orion, then decided to take a look at Lepus. I wanted to give that constellation a little bit of attention. There, I came across the double star consisting of TX and YZ Lep (while observing, I had no idea of their designations). It was easy to spot if one takes a line from Arneb to mu-Lep, and from its half-way point, take a perpendicular (horizon-side) roughly one-third the length of the first line and it's there. The stars are fairly close in brightness and did not have a color that stood out, so similar color and close enough to white for me not to tell. It stood out nicely in the binocular field of view. A nice target with low neck strain!

Thanks for sharing your observation, scroff. 

 

Here is a description I wrote about this double star aka S 476 (for James South) last March, included in this post.

 

S 476 / YZ Leporis
05h19m -18*31'
6.31/6.48 39.3" pa 19*

 

Two brilliant white stars, striking in 10x and 15x binoculars.

Edited by Fiske, 09 February 2023 - 12:26 AM.

[Fiske]

I'm looking forward to seeing that one, it's noted as S476 in my atlas.

 

Recently I visited gamma Lepus, it's pretty much on a straight line from Rigel Orion through Arneb to gamma, a distance total of about 16 degrees.  If you want to start at Arneb, there is a nice triangle consisting of Arneb, beta, and gamma, with beta further from Canis Major than gamma.  I think all 3 will fit into a 6-degree fov.  The numbers are 3.6/6.3 mag, 96" sep, and 350* PA.

From the same report in my reply to scroff. 

 

H 6 / Gamma Leporis
05h44m -22*27'
3.64/6.28 95.5" pa 349*

 

Deep yellow primary with orange secondary and a fantastic binocular double star suitable for lower magnification instruments. Not to be missed.

Edited by Fiske, 09 February 2023 - 12:26 AM.

[Fiske]

Soooo I looked at 

OCC 253

03h49m +24*23'

Aa/Ab 7.30/7.40 1.6" pa ??

 

Again...

 

Yesterday, after wheeling the 34x80 in I went to make/eat dinner and deal with the household pests personalities. Post that and an enthusiastic post on "What did you see last night in your binoculars..." I took out the BT-100 and did some doubles.

 

To begin with, went back to the beautiful

STF 616AB (Ome Aur)

04h 59m 15.41s +37° 53' 24.9" P.A. 5.00 sep 4.7 mag 5.00,8.21 Sp A1V dist. 52.27 pc (170.5 l.y.) 

 

Which was bright and really easy to split @56x. The BT-100 really shows it's strengths with mismatched doubles as there is very little glare.

 

I then went to look at a more challenging double:

STF 262AB (Iot Cas)

02h 29m 03.96s +67° 24' 08.7" P.A. 228.00 sep 3.0 mag 4.63,6.92 Sp A5pSr dist. 40.73 pc (132.86 l.y.)

Which was surprisingly easy to separate as well. Just shows the conditions.

 

Then I finally looked at 

OCC 253

03h49m +24*23'

Aa/Ab 7.30/7.40 1.6" pa ??

 

Really still, winter air. Transparent. Good conditions. Capable instrument aand no. Again, I could be convinced there is something there but I could not clearly separate a double nor even clearly see the elongation. I tried to wheel out the telescope but even at 240x I could not see anything realistically.

 

Sorry.

 

A fine report, Jordan. Thank you for sharing. 

 

About OCC 253, did you see this post from Chris in the Double Star forum?

Edited by Fiske, 09 February 2023 - 12:36 AM.

[Fiske]

How about this beauty in Auriga?

 

 

STF 644

05h10m +37*18m

6.96/6.78 1.6" pa 221*

 

 

[jrazz]

I did see that report... But you know... Had to verify! I mean, how could you trust GAIA data. It's only a space based 1.45m telescope. Ppffft. 

 

 

STF 644 - now THAT looks like fun!

In Auriga too (which is currently one of the fun constellations for me to observe)

 

Hopefully the wind dies down tonight and I can manage to look for it.

[jrazz]

See what you made me do? Happy?

It's 17°(F) outside. I left my poor BT-100 to equalize and by the time I got to it my hands were numb from touching it THROUGH MY GLOVES!

 

Weirdly bright night at 19.5 MPSAS and though it's clear the seeing isn't all that great. Something about the atmosphere... What is it... Ah yes! WIND! Did I mention the wind chill? No? IT WAS COLD!!!

 

 

Aaanyway, those are bygones and I bear no ill will even tough frostbite will remind me for a while. What did I look at? Straight up overhead. That's where this double decided to hang out. UGH! No pgram for the BT-100 so neck crane city here I come. (I might be slightly stubborn)

 

STF 644AB

05h 10m 18.81s +37° 18' 06.7" P.A. 221.00 sep 1.6 mag 6.96,6.78 Sp B2II+K3 dist. 485.44 pc (1583.51 l.y.)

 

So yeah. Even through the frostbite, wind chill, turbulence and the neck pain the BT-100/Pentax 10mm is still an awesome combo. I could just barely make it out but it is a nice, bright, yellowish double. I could not get a clear separation but it looked like two orbs joined. Definitely the limit of my vision and that of the BT.

 

It's a fantastic target for the bigger BTs and I plan on revisiting it with higher power (7mm and 5mm) once it goes slightly lower and the weather isn't as harsh.

[Fiske]

We are each responsible for our own choices, Jordan. 

 

Congratulations on partially resolving STF 644 with the 100XL at 56x -- a triumph!

 

  

[jrazz]

Last night was a battle between 80x (7mm) and 56x (10mm). Really interesting results.

The "image" is created by the objectives. The eyepieces just magnify it. The interesting part to me is that I don't see more detail in the 7mm meaning my LASIK is working just as well at 56x.  All this means is that I need more aperture.

 

Still, very happy with the BT-100. I think that 1.6" is probably the limit for this instrument and that's really impressive IMHO.

 

STF 644AB

05h 10m 18.81s +37° 18' 06.7" P.A. 221.00 sep 1.6 mag 6.96,6.78 Sp B2II+K3 dist. 485.44 pc (1583.51 l.y.)

Yup, can definitely see separation between the two. I know the classification says white and yellow but to me they seem both distinctly yellow. Fairly even and distinct. Bright too. Thank you Fiske for suggesting this one! It's a great test and really fun!

 

There are other fun doubles in Auriga though:

 

STF 845AB (41 Aur)

06h 11m 36.59s +48° 42' 39.6" P.A. 358.00 sep 7.5 mag 6.16,6.86 Sp A1V+A6V dist. 102.46 pc (334.22 l.y.)

I think I did this one before. It's a really nice, even, easily separated (at 80x) double. TBH it's probably an excellent 20x target. Very nice to look at. Two blueish/white stars that are surprisingly dim for a ~6 magnitude. Will probably revisit this one as it's fun!

 

STF 666 (the beast's double?)

05h 17m 05.80s +33° 19' 47.2" P.A. 75.00 sep 3.2 mag 7.85,7.89 Sp A3V

Well for having such a number it was surprisingly tame! Run of the mill white stars with a nice gap in between. Easy to find though my hands were freezing by this point. Just another cool double to wrap up the night.

 

I think I'm going to try for some of the easier Auriga doubles later in the week. Better gloves and a ZPB™ setup should help!

Happy Saturday to y'all!

[jrazz]

Yesterday turned out incredible!

20 MPSAS skies but with excellent transparency.

Seeing started as a mediocre "meh" 3/5 but progressed to some of the steadiest conditions I have ever seen. Quite remarkable I have to admit.

 

Definitely a night for double stars. I figured I'd knock some of the 5"-8" list out with my APM 34x80... Here's the resulting report:

 

STF 718AB

05h 32m 20.59s +49° 23' 36.5" P.A. 74.00 sep 7.7 mag 7.47,7.54 Sp F5 dist. 82.58 pc (269.38 l.y.)

Conspicuous. Two sharp, blue-white stars in a paucity of dimness. Quite pretty IMHO.

 

STF 845AB (41 Aur)

06h 11m 36.59s +48° 42' 39.6" P.A. 358.00 sep 7.5 mag 6.16,6.86 Sp A1V+A6V dist. 102.46 pc (334.22 l.y.)

I've done this one before. It's easy to find, just to the North/NW of Menkalinan. Two nicely separated blue-white stars. Really easy double to find and observe. Should be doable in a 20x.

 

STF1110AB (Castore)

07h 34m 35.86s +31° 53' 17.8" P.A. 51.60 sep 5.4 mag 1.93,2.97 Sp A1V+A4Vm dist. 15.6 pc (50.89 l.y.)

I've been looking at Castor a lot lately. It's the type of double that's really easy to find but with some setups not easy to split. Yes, the BT-100 can split it every time and so can the 34x80 but a 20x will struggle. Not that it's so close but the brightness makes it a challenge. I use it as a yardstick to gauge seeing.

 

STF1066 (Wasat)

07h 20m 07.39s +21° 58' 56.4" P.A. 229.00 sep 5.5 mag 3.55,8.18 Sp A9III+K3V dist. 18.54 pc (60.48 l.y.)

This has got to be one of my new favorites. It is a challenge in the 34x80. Separation is fine but the magnitude difference is tough. However, that secondary is very rewarding to see every time, plus you can just jump off to the Eskimo nebula which is awesome as well. 

 

Going a bit more South to Cancer:

 

STF1311AB

09h 07m 27.01s +22° 58' 51.1" P.A. 199.00 sep 7.5 mag 6.92,7.13 Sp F4V+F5V dist. 58.17 pc (189.75 l.y.)

This one was a piece of cake with the 34x80. Wide (for the things I have been observing lately), bright and even. Definitely on the "to try with 20x" pile.

 

STF1224A,BC (Ups Cnc)

08h 26m 39.82s +24° 32' 03.7" P.A. 53.00 sep 5.7 mag 6.92,7.53 Sp F0V+F7V dist. 79.74 pc (260.11 l.y.)

Oh good... My notes say "slightly yellow". I'm always cautious on colors because the conditions and observer can be so variable. I see color great but I'm no spectrometer and my binoculars no prisms. The secondary looked distinctly yellow but the primary less so.

 

STF1223 (Phi2 Cnc)

08h 26m 47.08s +26° 56' 07.8" P.A. 219.00 sep 5.2 mag 6.16,6.21 Sp A3V+A6V dist. 84.53 pc (275.74 l.y.)

Another really nice, bright and sharp double... All of these looked really sharp, you think the atmosphere was helping me?!? This one is relatively bright and though on the close end of the 34x capabilities I had no trouble splitting it. 

 

 

And finally, yes. I was saving it for last since I had been dreading it:

STF1196AB/C (Zet Cnc) - Tegmine

08h 12m 12.79s +17° 38' 51.2" P.A. 0.90 sep 1.1 mag 5.30,6.25 Sp F8V dist. 25.08 pc (81.81 l.y.)

08h 12m 12.79s +17° 38' 51.2" P.A. 64.20 sep 6.3 mag 4.92,5.85 Sp F8V dist. 25.08 pc (81.81 l.y.)

 

Tegmine had been a troublemaker for me. It sits right over the edge of what should theoretically be possible with 100mm of aperture. The AB/C separation is easy but the AB split is tough! I had to get the BT-100 and use the 3mm Televue Delites at 183x to see it. While I wasn't able to see a clean split I was able to see 2 distinct lobes touching. Definitely a record for me and something I think I will need a much bigger telescope to do better than. 

BTW, the "C" is also a double but I think you need 30" of aperture at the very least to see THAT.

 

 

Fun and incredible night of binocular double stars. Cloudy tonight but I hope to get more nights like this later in the summer.

[Fiske]

Following up on Jordan's report, over the past few nights I have observed STF 718 and reobserved STF 854 (41 Aur) in Auriga, previously reported in post 60 of this topic. My notes for STF 854 from last night, observing with an 82XL-SD and 14mm Pentax XWs (32x), state "Bright white primary with a yellowish secondary. Noticeable magnitude difference between the components. In a lovely star field."

 

I have not previously observed STF 718 and was very happy to add it to my double star life list, a fine double for 32x binoculars, which I was also able just to resolve with the 20x70 ED Ultra. 

 

STF 718

05h32m +49*24'

7.47/7.54 sep 7.7" pa 74*

82XL-SD+14XWs (32x): A pair of evenly matched warm white stars nestled together in the cleft of a faint rill of stars. Navigating to this double I noticed a lengthy and handsome stream of stars flowing east/west just north of Capella. 

 

Anyway, thank you Jordan! 

 

And my gift in return:

 

 

STF 1177

08h05m +27*32'

6.69/7.41 sep 3.5" pa 350*

A pair of bright white stars just resolved at 32x with the 82XL-SD and separated by a hair at 45x (with the Pentax 10mm XWs). Included in a fine arrow-shaped asterism crossing the border between Gemini and Cancer. A visual treat.

 

Edited by Fiske, 14 April 2023 - 06:12 PM.

[jrazz]

Sweet!! Thank you!

[jrazz]

Another interesting binocular double:

 

HJ 3945AB (145 Hya) - Also called the Winter Albiero

07h 16m 36.84s -23° 18' 56.1" P.A. 50.00 sep 26.5 mag 5.00,5.84 Sp K3Ib+dF0 dist. 434.78 pc (1418.25 l.y.)

 

I pilfered this from the Double Star observing forum. I think it's a cool double with a yellow star and a blue star. Just looks cool and has good, easy separation.

[jrazz]

Good double night yesterday. Sorry, the APM 34x80 was not up to the task of these doubles. The BT-100 with the Pentax 10mm eyepieces was though!!

 

STF1295 (17 Hya)

08h 55m 29.60s -07° 58' 15.9" P.A. 3.00 sep 4.0 mag 6.73,6.93 Sp A2m+A7m dist. 88.5 pc (288.69 l.y.)

This one was surprisingly hard to split at 56x. I think the separation might be over estimated and it's more along the lines of 3".

 

STF1260

08h 40m 41.40s -12° 10' 08.6" P.A. 301.00 sep 5.3 mag 7.86,8.07 Sp A2 dist. 139.28 pc (454.33 l.y.)

This one was much easier and I should have tried harder with the 34x80. I guess I was itching to get the BT out since it's so much more detailed. I observed this at 80x and it was easy to split with that.

 

ARG  72AB

08h 56m 49.69s -17° 26' 00.2" P.A. 183.00 sep 4.1 mag 7.23,7.40 Sp F3/5V dist. 62.31 pc (203.26 l.y.)

Really nothing to spectacular. It was on my list for some reason and I can't remember why. I usually try to pick interesting targets and I guess this is a challenge for the 34x80 but by the time I got to it I was in BT land so

 

STF1177 (17 Cnc)

08h 05m 37.06s +27° 31' 46.9" P.A. 350.00 sep 3.5 mag 6.69,7.41 Sp B9V dist. 294.12 pc (959.42 l.y.)

Yes, I know! I needed to try this out with the 34x80. Sorry. It would be a challenge and I think I will go back tonight and try it again since I said I would. I did try it at 23x and could not split it but could at 40x... Yes, 34x would really be a stretch but an interesting one. 

 

[gwlee]

One of the things implicit from someone eschewing mounted binoclars is that they are not concerned with detailed identification. 

 

Or, they prefer using a mounted telescope for detailed identification rather than a mounted binocular. 

[Fiske]

Another interesting binocular double:

 

HJ 3945AB (145 Hya) - Also called the Winter Albiero

07h 16m 36.84s -23° 18' 56.1" P.A. 50.00 sep 26.5 mag 5.00,5.84 Sp K3Ib+dF0 dist. 434.78 pc (1418.25 l.y.)

 

I pilfered this from the Double Star observing forum. I think it's a cool double with a yellow star and a blue star. Just looks cool and has good, easy separation.

I think the star is actually 145 CMa (not Hya) and the designation in StelleDoppie is incorrect. At any rate, the double star is certainly in Canis Major not Hydra. The RASC Double Star observing checklist has it as 145 CMa. (Page 2 of the checklist.)

Edited by Fiske, 16 April 2023 - 01:40 PM.

[jrazz]

I think both are options for the “Albireo” imposters.

 

Edit: I might be confused by Stella Doppie. Sky Safari does list it as CMa 145

Edited by jrazz, 16 April 2023 - 02:08 PM.