A nice colorful triple

[pepitoz]

I recently found out about a very nice binocular triple - here's some info about it!

You can find it 1 degree southeast of Gamma Ophiuchi and 1 degree southwest of 68 Ophiuchi. 

The stars are HIP 87491, A, HIP 87448, B, and HIP 87437, C. All stars are bright (6th and 7th mag), so they are easy to see in binoculars. The A-B/C separation is quite large (15') - however, because of the similar brightness, they really do look like a double. The A/B separation is much closer (60''), but still an easy split. A and B show an obvious red color, while C seems slightly blue to me. Very nice! 

This isn't a real binary system - the stars are a few hundred light years away from each other. I don't even know if this is cataloged! If someone knows, I'd be happy if they told me...

RA: 17h 52m 35s      DE: 01° 18'

Components         Magnitude             Color                                                           Separation

A                           5.90                       Red                                                            A and B/C - 15'          

B                           6.50                       Red                                                            B/C - 1'

C                           7.20                       Blue-white           

Check it out!

[BinocularSky]

You can find it 1 degree southeast of Gamma Ophiuchi and 1 degree southwest of 68 Ophiuchi. 

The stars are HIP 87491, [snip]

Sorry to correct you, but HIP 87491 is 1.8° SE ofγ Oph and 2.3° W of 68 Oph (68 & HIP87491 have as near as dammit the same declination).

   The A/B separation is much closer (60''), but still an easy split.

ITYM the B/C separation.

But yes, that is a lovely region of the sky: Mel 186,  which that triple is near, is a superb cluster for small binoculars. You've also got IC4665 nearby. I was looking around there a couple of evenings ago, but didn't notice that triple; I'll have to have a better look next time it's clear here; thanks for the heads-up.

[pepitoz]

Sorry to correct you, but HIP 87491 is 1.8° SE of γ Oph and 2.3° W of 68 Oph (68 & HIP87491 have as near as dammit the same declination).

ITYM the B/C separation.

But yes, that is a lovely region of the sky: Mel 186,  which that triple is near, is a superb cluster for small binoculars. You've also got IC4665 nearby. I was looking around there a couple of evenings ago, but didn't notice that triple; I'll have to have a better look next time it's clear here; thanks for the heads-up.

Thanks for correcting me

I wish I could edit my posts - now my mistakes will stay forever... or at least unil I reach 50 post

This really is a very interesting part of the sky - there are actually quite a few doubles and clusters here. Apparently, an open cluster known as Collinder 350 is close to the described triple. it's quite large, but I can't seem to find it with binoculars (I do see a busy starfield through a scope). Worth a try though!

Thanks for liking my post!

[BinocularSky]

Yes, Cr350 is there, but it's really difficult to distinguish as a cluster, being very sparse, but in quite a star-rich region. I find it easier to distinguish at low magnification (say 6x or 8x). It's actually in your drawing, in that triangle of stars that the "37" of "HIP87437" label protrudes into.

[Pete Presland]

I have never seen that one, thanks for the report another one added to the list

[Paul73]

Thanks for the post. Not a part of that sky that I have studied.

Looking forward to it.

Paul