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Rigel split

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#26 piyro


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Posted 08 January 2012 - 07:36 AM

Last night, with my new Vixen A70 Lf (70 mm f/13, but I was using it at 50 mm f/18) at 72x :woohoo:


#27 mseay


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Posted 25 January 2012 - 06:39 AM

Hey, Javier, what kind of setup and magnification were you using? I've been trying to split Rigel lately and am not sure if I need to go lower or higher...

#28 piyro


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Posted 25 January 2012 - 07:18 AM

Probably it is because of my location, by the sea in a medium town at 28 degrees north, but once I splitted Rigel for the first time, I have splitted it most nights. Last night, for example, at 36x, although I should recognize that was easier at 45x.


#29 Starman81



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Posted 28 November 2012 - 11:16 AM

I was viewing Jupiter and the moon through clouds last night and pointed the dob at the Rigel to star test my recent collimation. I was first-lighting a new-to-me 12mm Nagler T4 and had a 2x barlow with it in the focuser (200x). I was pleasantly surprised to find the unexpected companion (unexpected since I didn't know Rigel was a double and I was not trying to split it). A nice sight! I see from this thread that if I was aiming to split it cleanly I could use less power.

Side note: I put in the 12mm UO HD Ortho + 2x shorty barlow for the same 200x and noted that companion was brighter and easier to see. Not a surprise to most, I'm sure, but to me it was.

#30 mikey cee

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Posted 28 November 2012 - 11:24 PM

Hey Rob ol' boy that looks like an over exposed Jupiter and moons! :p Mike

#31 Kon Dealer

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Posted 29 November 2012 - 11:16 AM

Had a go last night after watching Ganymede transiting :)
Didn't expect much with all the glare from a full Moon and a milky sky, but it was a noticeable split at x87 and really clear at x122 (Kson102ED).

#32 WRAK



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Posted 12 January 2013 - 05:37 PM

Last night I had the opportunity to have a look at Rigel with my 140mm refractor. The glare of the primary was too intense to see the companion, for resolution it was necessary to reduce the aperture with a mask to 70mm - then the secondary was still rather faint for a +6.8mag star but clearly and stable to see.

#33 Cotts


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Posted 12 January 2013 - 07:41 PM

Checked 3 other references that indicate Rigel has only one visual companion. Recent observations seem to discount the early on observations of "B" being viewed as a tight .1" double.

From Wiki: Rigel B is itself a spectroscopic binary system, consisting of two main sequence stars that orbit their center of gravity every 9.8 days. The stars both belong to the spectral class B9V; Rigel B is the more massive of the pair, at 2.5 versus 1.9 solar masses.[18][19]
There was long-running controversy in the late 19th and early 20th century over the possible visible binarity of Rigel B. A number of experienced observers claimed to see it as a double, while others were unable to confirm it; indeed, the proponents themselves were sometimes unable to duplicate their results. Observations since have ruled out the likelihood of a visible companion to Rigel B.[18][19]

The scoop from the WDS:

05145-0812STF 668A,BC 1822 2011 117 201 204 8.9 9.3 0.3 6.8
05145-0812BU 555AD 1878 2008 6 2 1 44.5 44.6 0.3 15.4
05145-0812BU 555BC 1878 2005 25 55 30 0.3 0.1 7.5 7.6

Contradictory, it seems.... A spectroscopic binary with an orbital period of 9.8 days at the distance of Rigel (hundreds of light years) would not have a separation of 0.1" - more like 0.0001" or even closer...... I wonder what the WDS BC pair refers to or if it is an erroneous listing......


#34 fred1871



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Posted 12 January 2013 - 11:32 PM

Dave, the BC data line indicates 25 measures between 1878 and 2005. Many of these (18) are listed by SW Burnham in his 1900 catalog of his own discoveries. It is of course the obvious companion as a double. What's interesting here is the 2005 measure - without having the full WDS data we don't know if this is a speckle measure, as seems likely, given the 0.1" separation.

Curious, given as you say that a visible companion to Rigel B is unlikely. Agreed, it can't be the spectroscopic pair. Perhaps the 2005 measure might be evidence for the reality of Rigel B as a visual double after all. :question:

#35 Michael Morris

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Posted 25 January 2013 - 09:02 AM

Just observed Rigel for the first time. Easily seen with 8" LX200 Classic. Clear in both 13mm Type 6 Nagler and in University Optics 7mm orthoscopic. Nice steady, clearly define airey disc on primary. Companion seen a bright, sharp pin-star about same diameter as Airey disc again away to the south. Lovely.

#36 EdZ


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Posted 28 January 2013 - 06:53 PM

Rigel was an immediate split for me last week in my AT111 at 50x. Several other first timers at an outreach event also saw it.


#37 JIMZ7


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Posted 15 February 2013 - 10:54 PM

The other day it was sunny allday,but shortly as it got dark the clouds came rolling in. With my new used 10" scope I got a chance to look at Rigel at 57x. The spikes of the reflector actually looked pretty neat with the secondary star nearby. For the past 6 years I have been using refractor scopes to observe double stars & Rigel was one of those most viewed. What a difference without false colors! The night was getting worse fast so I tried 135x on Rigel. It was useless-very mushy looking so I called it a night even though it was very early evening. You can bet the next clear evening I will split Rigel once again.

Jim :dob:

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