Alpha Centauri

[telscope@xxxxxxxxxx (Peter Abrahams)]

There's nothing wrong with being off-topic, when the topic is astronomy.
It's not even as academic as it appears, since Alpha Centauri is visible,
low in the sky, to stereographers living 'below' the 29th parallel; however,
this low altitude will indeed play havoc with astrophotographic efforts.
At 4.34 light years (25 trillion miles,) its parallax is .751 arc seconds and
the proper motion is 3.68 arc seconds a year.  It is 2/3 of the closest
star system to the earth, and has the greatest known parallax and 
largest proper motion of any star.
I do not know if it is visible in a 10x glass, but it was found to be a binary
in 1689 (from India,) when considerably more powerful telescopes were
available--of uncertain resolving powers.  
Alpha Centauri is a binary, orbital period 80 years, and since the widest
recent separation will occur in 2000, and 2000-1689 = 311, very close
to the 320 years that 4 full orbits would take, the discovery was made at
approximate apastron (widest gap.)  It would seem that it is now 
resolvable as a binary at 10x, and with an orbit of 80 years, I don't think
that stellar motion would be a problem.
If stereoscopy fails, take heart, for Alpha Centauri is approaching us at
14 miles per second, and will certainly be stereoscopically resolvable
at some point in the future; even orthostereoscopically visible to our
lucky descendents.

Much more interesting is the discussion on stereoacuity and the 
extremely accurate retina/brain system that we possess.
I have found a few letters in the archives on this topic, and since
future posts should be correctly indexed, I will save my recitation
for a future article.  For now, I would appreciate it if the readers
knowledgeable in this field would post some of the better references
on the subject.
  
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telscope@xxxxxxxxxx (Peter Abrahams)          
the history of the telescope, 
     the prism binocular, and the microscope


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