More comets towards Alpha Centauri?
Abdul Ahad
interstellar debris on a hypothetical journey going out from our solar
system in the direction of Alpha Centauri, compared to any other
direction. This is a point which I theorise in my research article
at:-
http://uk.geocities.com/aa_spaceagent/restricted/interstellar-propulsion.html
Going out from the Sun in the direction of Alpha Centauri, at around
(c. 70,000 - 120,000 AUs solar distance), where the individual
gravitational spheres of influence of the Sun and Alpha Centauri
intersect and merge into each other, the orbital speeds of any comets
slow right down. So is it feasible to assume they would concentrate in
a 'pool' in this region hanging in a gravity equilibrium between both
systems?
Based on an analysis of the arrival and departure trajectories of all
non-periodic comets in and out of our solar system over the past 300
years, is it possible to show that a greater (statistically
significant) number come from the general direction of Alpha Centauri,
compared to all other directions in the sky?
If we analys all comets with orbital eccentricity, e > 0.99 (very long
periodic) to e >= 1 (parabolic, hyperbolic never returning), then it
may just show some results that can confirm this. Where can I find a
list of all comets and orbital data over past 300 years?
Quote of the assertions in my article:-
"The "mid-range" which I refer to here, is a *gravitational* mid range
centered on approx. 90,000 AUs solar distance - a third of the total
linear distance separating our Sun from Alpha Centauri. At that
distance, an object's orbital period, given by Kepler's 3rd law:-
a^3 = k * T^2
[ where a = semi-major axis of orbit, T = orbital period and k =
Gaussian gravitational constant ]
would be no less than 27 million years! Since this territory is
effectively a "no man's land", where an object would be equally
gravitationally perturbed by both systems, it is quite conceivable
that material could accumulate here and more comets and icy debris
could be encountered on a voyage going towards Alpha Centauri compared
to any other direction. "
[[Mod. note -- You might also want to try posting over in
sci.space.science, as a lot of planetary-science people seem to
read/post there. -- jt]]
Hynee
do this yourself. -- jt]]
"Abdul Ahad" <aa_spa...@yahoo.co.uk> wrote in message
news:mt2.1-14878...@sshserv.aei.mpg.de...
> Going out from the Sun in the direction of Alpha Centauri, at around
> (c. 70,000 - 120,000 AUs solar distance), where the individual
> gravitational spheres of influence of the Sun and Alpha Centauri
> intersect and merge into each other, the orbital speeds of any comets
> slow right down. So is it feasible to assume they would concentrate in
> a 'pool' in this region hanging in a gravity equilibrium between both
> systems?
The gravitation null point (perhaps not the official term) between two
massive objects is a saddle--basically it's unstable to small perturbations.
So its unlikely any objects will congregate there. If the stars are orbiting
each other, the Lagrangian points may come into play, but A Cen and the sun
are only orbiting the centre of the galaxy, not each other.
colone...@yahoo.com
> I was hoping to find out if we would encounter more comets and
> interstellar debris on a hypothetical journey going out from our solar
> system in the direction of Alpha Centauri, compared to any other
> direction.
In addition to any effect causing comets thenselves to concentrate in the
direction of Alpha Centauri, would gases concentrate in this region and
thus tend to accrete more material onto the comets? Thus you might have
more and/or larger comets.
3ch
[[Mod. note -- As another poster has pointed out, there's no reason
to expect *any* concentration in this region -- it's an *unstable*
"saddle point" of the gravitational field. -- jt]]
Mike Dworetsky
do this yourself. -- jt]]
"Abdul Ahad" <aa_spa...@yahoo.co.uk> wrote in message
news:mt2.1-14878...@sshserv.aei.mpg.de...
> Going out from the Sun in the direction of Alpha Centauri, at around
> (c. 70,000 - 120,000 AUs solar distance), where the individual
> gravitational spheres of influence of the Sun and Alpha Centauri
> intersect and merge into each other, the orbital speeds of any comets
> slow right down. So is it feasible to assume they would concentrate in
> a 'pool' in this region hanging in a gravity equilibrium between both
> systems?
As far as I am aware, there is no extra concentration of orbit major axes of
"first-time" comets in the direction of Alpha Cen. There was a proposal a
couple of years ago by John Murray that there was an excess of these towards
somewhere in the N hemisphere but the result is disputable.
It is unlikely that Alpha Cen is perturbing currently viewed comets towards
the solar system. The Sun and Alpha Cen are moving past one another fast
enough that the encounter is much shorter than the period of a 90000 AU
object.
--
Mike Dworetsky
(Remove "pants" spamblock to send e-mail)
colone...@yahoo.com
> "Abdul Ahad" <aa_spa...@yahoo.co.uk> wrote in message
> news:mt2.1-14878...@sshserv.aei.mpg.de...
> > (c. 70,000 - 120,000 AUs solar distance), where the individual
> > gravitational spheres of influence of the Sun and Alpha Centauri
> > intersect and merge into each other, the orbital speeds of any comets
> > slow right down.
thus the object have -more- KE? --Consider an object traveling straight
toward Alpha Centauri. Normally it would have decelerated a certain amount
at a certain distance but now AC has also accelerated it toward itself, so
it would not have slowed as much as it would have w/o AC's influence (and
will start accelerating toward AC if it travels far enough).
> > So is it feasible to assume they would concentrate in
> > a 'pool' in this region hanging in a gravity equilibrium between both
> > systems?
>
> The gravitation null point (perhaps not the official term) between two
> massive objects is a saddle--basically it's unstable to small perturbations.
For a stationary or orbiting object, but I believe the question was
concerning objects passing through which slow down & spend more time in
a region, --like a planet tends to spend more time further from the
primary (and at a higher potential).
3ch
AA Institute
> On Sat, 4 Sep 2004, Hynee wrote:
> > "Abdul Ahad" <aa_spa...@yahoo.co.uk> wrote in message
> > news:mt2.1-14878...@sshserv.aei.mpg.de...
> > > (c. 70,000 - 120,000 AUs solar distance), where the individual
> > > gravitational spheres of influence of the Sun and Alpha Centauri
> > > intersect and merge into each other, the orbital speeds of any comets
> > > slow right down.
> thus the object have -more- KE? --Consider an object traveling straight
> toward Alpha Centauri.
The slower speeds I am quoting here are speeds in the orbital sense of
bodies going around the Sun (or, in the neighbouring system, around
Alpha Cen). So for example Mercury moves around the Sun much more
rapidly than say Pluto; Pluto moves much more rapidly compared to a
more distant body like Sedna (outer KBO), etc.
> Normally it would have decelerated a certain amount
> at a certain distance but now AC has also accelerated it toward itself, so
> it would not have slowed as much as it would have w/o AC's influence (and
> will start accelerating toward AC if it travels far enough).
>
> > > So is it feasible to assume they would concentrate in
> > > a 'pool' in this region hanging in a gravity equilibrium between both
> > > systems?
> >
> > The gravitation null point (perhaps not the official term) between two
> > massive objects is a saddle--basically it's unstable to small perturbations.
> For a stationary or orbiting object, but I believe the question was
> concerning objects passing through which slow down & spend more time in
> a region, --like a planet tends to spend more time further from the
> primary (and at a higher potential).
That is indeed the point I am making. Yes at the *precise* point of
equilibrium between the gravititational forces from each system there
will exist a "knife edge" scenario, where bodies would be perturbed
into a rapid motion towards either star (whichever star 'wins' the
body so to speak with its greater gravitational might!)
But leading up to that precise point of equilibrium, I would expect
orbits of objects around each star (Sun, Alpha Cen) to be pulled and
stretched toward a middle ground, where the respective *aphelia* of
orbiting bodies have a commonly oriented major-axis line of orbits
which lines up with a line connecting the Sun and the barycentre of
the Alpha Centauri system. I have tried to illustrate this here:-
http://uk.geocities.com/aa_spaceagent/restricted/interstellar-propulsion.html#midrange
Since more time is spent by orbiting bodies towards the "aphelia"
points of their orbits, it is likely (from a theoretical point of
view) to expect more bodies to be found travelling to Alpha Centauri,
compared to all other directions outward from the Sun.
Would that ring 'about right' to most folk out there?
Thanks for all thoughts, sincerely appreciated.
Abdul Ahad