Re: constellation question

From: Paul Schlyter (pausch_at_saaf.se)
Date: 06/20/04 

Date: Sun, 20 Jun 2004 09:43:38 GMT

In article <cb3fok$2dnc$3@news.cybercity.dk>, Laura <laura@nospam.me> wrote:
> "Tim923" <tws0923@verizon.net> wrote in message
> news:jht9d0hd71oampqsfu7d4jovran1celmdk@4ax.com...
>> I assumed that stars in a constellation weren't actually close to each
>> other in space, that they only appeared close in our 2D viewing of
>> them, but I have a galaxy picture that would suggest otherwise.
>> Clarification?
>
> Some will be closer to each other than others, but there is no rule that
> they have to be close. Some are very close, such as the Pleiades, because
> that constellation is also a star cluster.
> http://www.ras.ucalgary.ca/~gibson/pleiades/
> In others, such as Orion, the distance of the individual stars varies a
> great deal.
>
> Naturally, the stars of all constellations will be within a certain distance
> from earth (but that distance is very large). The constallations were
> defined long ago by viewing the stars with the naked eye, and none of the
> really distant and faint ones can be seen that way.

There's no requirement that a star has to be visible to the naked eye
to be situated in a constellation. Consider for instance Proxima
Centauri: it's magnitude 14 and thus far too faint to be visible to
the naked eye, yet it is situated in the constellation Centaurus.

In ancient times, constellations were defined by the constellation
figures, and the boundaries between the constellations were very
vaguely defined. There were even areas of the sky considered to not
belong to any constellation at all. In the 1700's this situation
started to change: stellar cartographists started to draw
constellation boundaries, and new constellations were invented to
fill in the areas of the sky having no constellation. And in 1930
the IAU defined the constellation boundaries rigorously. So today,
no matter what star you consider and no matter how faint, it belongs
to a constellation. Occasionally, the proper motion of a star
carries it from one constellation to another. 

-- 
----------------------------------------------------------------
Paul Schlyter,  Grev Turegatan 40,  SE-114 38 Stockholm,  SWEDEN
e-mail:  pausch at stockholm dot bostream dot se
WWW:     http://www.stjarnhimlen.se/
         http://home.tiscali.se/pausch/

Relevant Pages

  • Re: CUBS SCIENTIST BADGE
    ... shoebox, black card, black paint and brush, ... mark out the star positions for each constellation on each ... Use bigger holes for brighter stars. ... Compact constellations with a number bright stars (certainly brighter than ...
    (uk.rec.scouting)
  • Re: Cherokee #3 Pronto & Cygnus (Part I)
    ... Wow - I can only imagine how big ... Cascade is a pretty miserable constellation, is larger in terms of its ... ninth magnitude stars. ... which lies in the constellation of Vulpecula the Wolf. ...
    (sci.astro.amateur)
  • Re: constellation question
    ... They can be at any distance from us. ... > in the Plough are part of a cluster (it's not a modern constellation, ... That's not an exception of "the rule", which merely says that stars ...
    (sci.astro)
  • Re: Life as a law of physics?
    ... In this system the Pleiades ... Names of stars and star clusters are not. ... chosen to define a constellation - as an area of sky. ...
    (talk.origins)
  • Re: constellation question
    ... >> I assumed that stars in a constellation weren't actually close to each ... They can be at any distance from us. ... >Deneb is approx. ...
    (sci.astro)
Quantcast