--- On Mon, 5/18/09, erikhansen@TheBlueZone.net <erikhansen@TheBlueZone.net> wrote:
From: erikhansen@TheBlueZone.net <erikhansen@TheBlueZone.net> Subject: Re: [Utah-astronomy] Albireo: a double star? To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Monday, May 18, 2009, 3:24 PM
I searched the web for Hipparcos info no luck, good luck to somebody else, I am sure they don't refer to it as Alberio.
Chuck, I suggest we see if it gets down to liberal vs conservative POV. As a liberal I say it is a physical pair.
Erik: The Wiki data references the Hipparcos data in the footnotes. Hipparcos did extend our knowledge greatly over what we could gleen from the ground, but it left the Albireo question unresolved. A newer more powerful Astrometry satellite named Gaia is supposed to greatly extend our reach for this type of question. In the mean time we need to remember that male support group on the Red Green show where men try to learn the three little words that are so hard for them to say....."I don't know". DT
Daniel is correct. Hipparchos' accuracy was about 0.001 arc-second, so if a system displayed less paralactic shift or orbital motion than that during the data-taking phase, it's motions remained unresolved. I dug out the Millenium Star Atlas and no proper motion data or distance is even indicated for Beta Cygni. Orbital parameters are beyond the purview of the Atlas. Erik, you maintain that it's a physical pair, but currently only a handful of states recognize that officially, and Utah isn't likely to be one of them anytime soon... ;o)
Dan,
My insistence was tongue in cheek, when I talk to public I will say some doubles are physical and some optical. I will say I believe one may be a physical pair but that I am not certain. It really makes little real difference. Alberio appears to one that if it is a physical pair the orbital period is so long that is difficult for humans to detect. It remains one of the most beautiful pairs in the sky. It is only recently I have paid any heed to position angle and I plan to follow a few doubles that this change can be observed. I suspect my list contained a typo and I am striking it from my list. It was compiled before the internet existed, perhaps I missed a notation. The discussion was valuable since it found an error in my list. Erik
--- On Mon, 5/18/09, erikhansen@TheBlueZone.net <erikhansen@TheBlueZone.net> wrote:
From: erikhansen@TheBlueZone.net <erikhansen@TheBlueZone.net> Subject: Re: [Utah-astronomy] Albireo: a double star? To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Monday, May 18, 2009, 3:24 PM
I searched the web for Hipparcos info no luck, good luck to somebody else, I am sure they don't refer to it as Alberio.
Chuck, I suggest we see if it gets down to liberal vs conservative POV. As a liberal I say it is a physical pair.
Erik:
The Wiki data references the Hipparcos data in the footnotes. Hipparcos did extend our knowledge greatly over what we could gleen from the ground, but it left the Albireo question unresolved. A newer more powerful Astrometry satellite named Gaia is supposed to greatly extend our reach for this type of question.
In the mean time we need to remember that male support group on the Red Green show where men try to learn the three little words that are so hard for them to say....."I don't know".
DT
_______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php Visit the Wiki: http://www.utahastronomy.com
participants (3)
-
Chuck Hards -
daniel turner -
erikhansen＠TheBlueZone.net