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Outer edges of our solar system were disturbed by passing star, may
contain more bodies out there- http://www.spaceflightnow.com/news/n0412/01passingstar/ Didn't Ahad say something similar in his Oort cloud mission to Alpha Cen back in August: "From a dynamical perspective, as predicted by Isaac Newton's well known gravity equation: F=G(m1*m2)/r^2 the Sun's sphere of influence reaches well beyond the distance of Alpha Centauri. Add to this the fact that the Sun has made some 20 revloutions around the Milky Way galaxy since its formation [4,500 million years (age) / 225 million years (galactic rotation period)] and within that time, it is certain to have passed through dense gas clouds, star and planet forming regions, brushing the outer edges of proto-planetary disks of other stars, attracting and shedding swarms of comets... There is every reason to be hopeful of swarms of comets existing much further out than those within current detection range of our instruments. " This quote from: http://uk.geocities.com/aa_spaceagen...ropulsion.html |
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"dreamer" wrote in message
m... Outer edges of our solar system were disturbed by passing star, may contain more bodies out there- http://www.spaceflightnow.com/news/n0412/01passingstar/ Didn't Ahad say something similar in his Oort cloud mission to Alpha Cen back in August: "From a dynamical perspective, as predicted by Isaac Newton's well known gravity equation: F=G(m1*m2)/r^2 the Sun's sphere of influence reaches well beyond the distance of Alpha Centauri. The Sun's gravitational sphere of influence ends when the infuence of other bodies becomes greater than its own. What's the density of stars in the neighborhood of the Sun? It's roughly 25 star systems in a volume of roughly 10,000 cubic light years. So we have about 13.6 cubic light years per star on average. Mean distance between stars will be given by the cube root of the volume per star, or about 7.2 light years. Assuming an average mass for the stars, then the gravitational sphere of influence won't extend past the halfway point to the next star. So in our stellar neighborhood the radius of the sphere of influence will be about 3.6 ly, which is not quite as far as Alpha Centauri at 4.3 ly. Add to this the fact that the Sun has made some 20 revloutions around the Milky Way galaxy since its formation [4,500 million years (age) / 225 million years (galactic rotation period)] and within that time, it is certain to have passed through dense gas clouds, star and planet forming regions, brushing the outer edges of proto-planetary disks of other stars, attracting and shedding swarms of comets... There is every reason to be hopeful of swarms of comets existing much further out than those within current detection range of our instruments. " The above seems to assume that the rest of the galaxy is motionless while the Sun sails through it. The stars and other contents of the local volume of space surrounding the Sun can have similar periods of revolution around the galactic core, and so it is possible that the Sun takes its environment with it as it goes. Now, this is not necessarily true, but it is possible. Declaring that "it is certain to havbe passed through dense gas clouds, star and planet forming regions,..." seems to be taking a bit of a leap. This quote from: http://uk.geocities.com/aa_spaceagen...ropulsion.html |
#3
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But if we're to believe the cosmologists, stars only represent about 1%
of the total matter. Another 4% is interstellar gas and neutrinos, and the remaining 95% is Unobservium. Deep thinkers and mathematicians tell us Unobservium is made up of 23% dark matter, and 72% dark energy. The dark matter cannot be observed, but it supposedly has profound gravitational influence. And the all-important dark energy is crucial as it fills an empty spot in the curvature equations. So your stellar "spheres of influence model" must be adjusted accordingly. As we sit here today, a lump of dark matter may be tugging at ol' Sol's happy little orbit, or stirring the Oort cloud into mischief! Personally, I'm a little skeptical of the latest theories. I prefer the traditional model where the universe is carried on the back of a rather large turtle. Greg Neill wrote: "dreamer" wrote in message m... Outer edges of our solar system were disturbed by passing star, may contain more bodies out there- http://www.spaceflightnow.com/news/n0412/01passingstar/ Didn't Ahad say something similar in his Oort cloud mission to Alpha Cen back in August: "From a dynamical perspective, as predicted by Isaac Newton's well known gravity equation: F=G(m1*m2)/r^2 the Sun's sphere of influence reaches well beyond the distance of Alpha Centauri. The Sun's gravitational sphere of influence ends when the infuence of other bodies becomes greater than its own. What's the density of stars in the neighborhood of the Sun? It's roughly 25 star systems in a volume of roughly 10,000 cubic light years. So we have about 13.6 cubic light years per star on average. Mean distance between stars will be given by the cube root of the volume per star, or about 7.2 light years. Assuming an average mass for the stars, then the gravitational sphere of influence won't extend past the halfway point to the next star. So in our stellar neighborhood the radius of the sphere of influence will be about 3.6 ly, which is not quite as far as Alpha Centauri at 4.3 ly. Add to this the fact that the Sun has made some 20 revloutions around the Milky Way galaxy since its formation [4,500 million years (age) / 225 million years (galactic rotation period)] and within that time, it is certain to have passed through dense gas clouds, star and planet forming regions, brushing the outer edges of proto-planetary disks of other stars, attracting and shedding swarms of comets... There is every reason to be hopeful of swarms of comets existing much further out than those within current detection range of our instruments. " The above seems to assume that the rest of the galaxy is motionless while the Sun sails through it. The stars and other contents of the local volume of space surrounding the Sun can have similar periods of revolution around the galactic core, and so it is possible that the Sun takes its environment with it as it goes. Now, this is not necessarily true, but it is possible. Declaring that "it is certain to havbe passed through dense gas clouds, star and planet forming regions,..." seems to be taking a bit of a leap. This quote from: http://uk.geocities.com/aa_spaceagen...ropulsion.html |
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"Tim Killian" wrote in message
... But if we're to believe the cosmologists, stars only represent about 1% of the total matter. Another 4% is interstellar gas and neutrinos, and the remaining 95% is Unobservium. Deep thinkers and mathematicians tell us Unobservium is made up of 23% dark matter, and 72% dark energy. The dark matter cannot be observed, but it supposedly has profound gravitational influence. And the all-important dark energy is crucial as it fills an empty spot in the curvature equations. So your stellar "spheres of influence model" must be adjusted accordingly. As we sit here today, a lump of dark matter may be tugging at ol' Sol's happy little orbit, or stirring the Oort cloud into mischief! If the background mass is more or less uniformly distributed, it will not influence the spheres of influence (so to speak) of the "point source" stars. If something substantial was tugging differentially on Sol, it would have shown up in the Hipparcos results, no? Personally, I'm a little skeptical of the latest theories. I prefer the traditional model where the universe is carried on the back of a rather large turtle. :-) |
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On Mon, 13 Dec 2004 11:09:25 -0500, "Greg Neill"
wrote: Personally, I'm a little skeptical of the latest theories. I prefer the traditional model where the universe is carried on the back of a rather large turtle. :-) Reminded me of this.... http://www.the-funneled-web.com/hawking.htm |
#6
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With you all the way on the Turtle model
"Tim Killian" wrote in message ... But if we're to believe the cosmologists, stars only represent about 1% of the total matter. Another 4% is interstellar gas and neutrinos, and the remaining 95% is Unobservium. Deep thinkers and mathematicians tell us Unobservium is made up of 23% dark matter, and 72% dark energy. The dark matter cannot be observed, but it supposedly has profound gravitational influence. And the all-important dark energy is crucial as it fills an empty spot in the curvature equations. So your stellar "spheres of influence model" must be adjusted accordingly. As we sit here today, a lump of dark matter may be tugging at ol' Sol's happy little orbit, or stirring the Oort cloud into mischief! Personally, I'm a little skeptical of the latest theories. I prefer the traditional model where the universe is carried on the back of a rather large turtle. Greg Neill wrote: "dreamer" wrote in message m... Outer edges of our solar system were disturbed by passing star, may contain more bodies out there- http://www.spaceflightnow.com/news/n0412/01passingstar/ Didn't Ahad say something similar in his Oort cloud mission to Alpha Cen back in August: "From a dynamical perspective, as predicted by Isaac Newton's well known gravity equation: F=G(m1*m2)/r^2 the Sun's sphere of influence reaches well beyond the distance of Alpha Centauri. The Sun's gravitational sphere of influence ends when the infuence of other bodies becomes greater than its own. What's the density of stars in the neighborhood of the Sun? It's roughly 25 star systems in a volume of roughly 10,000 cubic light years. So we have about 13.6 cubic light years per star on average. Mean distance between stars will be given by the cube root of the volume per star, or about 7.2 light years. Assuming an average mass for the stars, then the gravitational sphere of influence won't extend past the halfway point to the next star. So in our stellar neighborhood the radius of the sphere of influence will be about 3.6 ly, which is not quite as far as Alpha Centauri at 4.3 ly. Add to this the fact that the Sun has made some 20 revloutions around the Milky Way galaxy since its formation [4,500 million years (age) / 225 million years (galactic rotation period)] and within that time, it is certain to have passed through dense gas clouds, star and planet forming regions, brushing the outer edges of proto-planetary disks of other stars, attracting and shedding swarms of comets... There is every reason to be hopeful of swarms of comets existing much further out than those within current detection range of our instruments. " The above seems to assume that the rest of the galaxy is motionless while the Sun sails through it. The stars and other contents of the local volume of space surrounding the Sun can have similar periods of revolution around the galactic core, and so it is possible that the Sun takes its environment with it as it goes. Now, this is not necessarily true, but it is possible. Declaring that "it is certain to havbe passed through dense gas clouds, star and planet forming regions,..." seems to be taking a bit of a leap. This quote from: http://uk.geocities.com/aa_spaceagen...ropulsion.html |
#7
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test post
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#8
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"ed mcdermott" wrote:
test post You failed. Tim -- This is not my signature. |
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