Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Double star-possibly Zeta Sagittarii?

double star
  • Please log in to reply
8 replies to this topic

#1 SillySMS

SillySMS

    Lift Off

  • -----
  • topic starter
  • Posts: 4
  • Joined: 07 Aug 2019
  • Loc: Austin, TX

Posted 13 August 2019 - 06:14 PM

Yesterday was my third night out with a scope, and while attempting to view Saturn, I first zoomed in on what I'm pretty sure was a double star in the Sagittarius constellation, about 10-ish degrees below and to the right of where Saturn actually was.

 

I think it was Zeta Sagittarii, but I'm not 100% sure. Both components were yellow and approximately the same brightness. They were clearly distinct on a 70mm refractor at 200x magnification. It was a fairly bright star; I mistook it for Saturn, after all.

 

Does Zeta Sagittarii sound like a correct identification?

 

On a side note: Saturn's rings are amazing, even with a telescope just barely able to make them out.



#2 Barlowbill

Barlowbill

    Viking 1

  • *****
  • Posts: 563
  • Joined: 05 Apr 2018
  • Loc: Tulsa, Oklahoma

Posted 13 August 2019 - 06:27 PM

Saturn is always amazing if you can at least see black background between the rings and the planet.  Look up the star on Wike!


  • SillySMS likes this

#3 S.Boerner

S.Boerner

    Apollo

  • *****
  • Posts: 1198
  • Joined: 29 Apr 2010
  • Loc: Chesterfield, MO

Posted 13 August 2019 - 06:31 PM

Checking in SkySafari shows the separation for the doubles of zeta Sgr is 0.4" arcminutes.  That's pretty small.  I poked around a bit but didn't find anything better.


  • SillySMS likes this

#4 ShaulaB

ShaulaB

    Surveyor 1

  • *****
  • Posts: 1590
  • Joined: 11 Oct 2012
  • Loc: Missouri

Posted 13 August 2019 - 06:32 PM

A good app for a phone or a tablet is called Sky Safari. Lots of the cool kids here use it.


  • SillySMS likes this

#5 Cotts

Cotts

    Just Wondering

  • *****
  • Moderators
  • Posts: 9811
  • Joined: 10 Oct 2005
  • Loc: Madoc, Ontario

Posted 13 August 2019 - 07:29 PM

Zeta Sgr has a separation of only 0.4".  Arc seconds!   that's almost impossibly close for most amateur telescopes..  I'm sure your 70mm at 200x will not split it...

 

I had a look at all the brighter stars in Sagittarius and none seems to fit your description...

 

Perhaps you could find it again and make a sketch of the field with Saturn and the brighter stars in it.....

 

Dave


  • havasman likes this

#6 starblue

starblue

    Ranger 4

  • -----
  • Posts: 344
  • Joined: 01 Apr 2015
  • Loc: Austin, TX, USA

Posted 15 August 2019 - 06:49 PM

One possibility is SAO 209802. It's close to gamma-2 Sgr with stars mags 5.53 and 5.77, separation 4.1", and spectrum F0V (yellow-orange) (stats from Sky Safari 6). In a small scope a 5th mag star would appear much brighter, and it'd be easy to think you were on gamma-2 when really you were just off it on this star instead.


  • Jon Isaacs likes this

#7 Sky Muse

Sky Muse

    Fly Me to the Moon

  • *****
  • Posts: 7193
  • Joined: 26 Oct 2012
  • Loc: Mid-South, U.S.

Posted 16 August 2019 - 10:46 AM

It sounds to me like you saw Saturn's largest moon, Titan.  In my refractors, Titan usually appears to the right of and a little below the planet..



#8 JOEinCO

JOEinCO

    Viking 1

  • *****
  • Posts: 592
  • Joined: 28 Sep 2017
  • Loc: Colorado Front Range

Posted 16 August 2019 - 01:03 PM

It sounds to me like you saw Saturn's largest moon, Titan.  In my refractors, Titan usually appears to the right of and a little below the planet..

Could be, but how did it appear double? Anyway, that is not why I posted. 

 

Titan orbits Saturn. It's position changes every night. It can certainly be to Saturn's lower right, but Titan can be anywhere on it's (currently highly) elliptical orbit around Saturn.



#9 Sky Muse

Sky Muse

    Fly Me to the Moon

  • *****
  • Posts: 7193
  • Joined: 26 Oct 2012
  • Loc: Mid-South, U.S.

Posted 17 August 2019 - 08:53 AM

Could be, but how did it appear double? Anyway, that is not why I posted. 

 

Titan orbits Saturn. It's position changes every night. It can certainly be to Saturn's lower right, but Titan can be anywhere on it's (currently highly) elliptical orbit around Saturn.

Yes, Titan orbits Saturn.  Practically everything in the sky orbits something or other.  It is strange that up until the other night, it has always appeared to be at the lower-right of the planet, even through my 6" f/5 Newtonian; coincidence?  The other night, through my Maksutov, Titan appeared opposite of that, at the upper left, and for the first time ever; perhaps something to do with the optical configuration.  I just got that Maksutov recently, so I wasn't too surprised by that.  Maybe I should stick with the "Old Ones", refractors and Newtonians, and for less confusion.

 

In any event, perhaps it wasn't Titan, nor Zeta Sagittarii which is a blue-white star.  The star is also known as "Ascella", and is a triple-star system...

 

https://i.imgur.com/lREQzl8.jpg

 

I would say that we would have to have been there with the OP at the time, for us to have a look, and to know for certain.  I have a stellar view to the south, and of the "Teapot", so I will be observing the star in question myself, and to make certain that it isn't yellow.  Who knows, I may also run across what the OP claims they saw.  The star is located at the bottom of the asterism's "handle".

 

I think we all should have a look one night soon, before the cold winds begin to blow, and instead of going out to eat and/or "party", or staying indoors and watching television.  

 

I think I'll use my 5" "Bird Jones" for the event.  I was seeing double with it after it had first arrived, but I have it well-collimated now, and it's excellent for the higher powers of which the telescope is capable.  I'll even try to split it, despite the nays from the gallery.  After all, it's only 88 light-years distant.




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics





Also tagged with one or more of these keywords: double star



Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics