Abdul Ahad wrote:
So I would say, from a perspective of gravitational interactivity, the
Sirius system is relatively *far removed*... but you have every right
to disagree of course!
And I do. I still think you are entranced by this idea of the Sun and
alpha Centauri as being partners in space, when they very clearly are
not. Since the gravitational influence of Sirius on alpha Centauri is
just about half that of the Sun's, I wouldn't call that at all far
removed. Further removed, yes, but somebody has to be closest. That
doesn't say anything about whether we're bound to each other. And, as
it happens, we are not.
So if Alpha Centauri is not gravitationally *connected* with the Sun,
are you saying that its just another passing star system?
Yes. We've said that a number of times, now.
Is there a
3D model available to show the projected distances separating Sun from
Alpha Centauri on a time-series basis like this:-
Epoch: Distance:
================================================== ============
Now - 1 million years ?
Now - 500,000 years ?
Now - 100,000 years ?
Now 4.3 LY
Now + 1 million years ?
Now + 500,000 years ?
Now + 100,000 years ?
You can construct one very simply from available three-dimensional
velocity data. From the Doppler shift, one gets the velocity along the
line connecting us and alpha Centauri; from the proper motions, one
gets the velocity in the plane perpendicular to that line. Combine
that, and you can derive the values in the table above.
What about extrasolar planet detection efforts around Alpha Centauri,
to your knowledge?
To my knowledge, such efforts have been unsuccessful in detecting planets
around alpha Centauri A, B, or C. That doesn't mean that there aren't
any planets around any of those stars--only that if there are, they are
too small (or, just conceivably, in an orbital plane that is too close to
perpendicular to our line of sight) to have been detected yet.
Brian Tung
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