View Full Version : My paper on dynamical stability of an Earth ring
AA Institute
Dec4-04, 03:13 PM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>I have drafted a paper that mathematically demonstrates the physical\nimpossibility for a ring system to remain stable around the Earth,\nwhen hitherto most experts were either unsure or mistakenly believed\nthat such a ring system could in fact hold together:-\n\nhttp://uk.geocities.com/aa_spaceagent/restricted/earth-ring-dynamics.html\n\nMy question is which peer reviewed, refereed journal would be a good\nplace to send this paper to? I am based in the UK, so would it be\nacceptable in the US astrophysical journal? Is there a Physics journal\nthat I can send it to?\nThanks for all pointers,\nAbdul Ahad\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>I have drafted a paper that mathematically demonstrates the physical
impossibility for a ring system to remain stable around the Earth,
when hitherto most experts were either unsure or mistakenly believed
that such a ring system could in fact hold together:-
http://uk.geocities.com/aa_spaceagent/restricted/earth-ring-dynamics.html
My question is which peer reviewed, refereed journal would be a good
place to send this paper to? I am based in the UK, so would it be
acceptable in the US astrophysical journal? Is there a Physics journal
that I can send it to?
Thanks for all pointers,
Abdul Ahad
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\nadul.ahad@ntlworld.com writes:\n>\n>I have drafted a paper that mathematically demonstrates the physical\n>impossibility for a ring system to remain stable around the Earth,\n>when hitherto most experts were either unsure or mistakenly believed\n>that such a ring system could in fact hold together:-\n>\n>http://uk.geocities.com/aa_spaceagent/restricted/earth-ring-dynamics.html\n>\n>My question is which peer reviewed, refereed journal would be a good\n>place to send this paper to? I am based in the UK, so would it be\n>acceptable in the US astrophysical journal? Is there a Physics journal\n>that I can send it to?\n>Thanks for all pointers,\n>Abdul Ahad\n>\n\nI\'m not exactly sure which journal to send something like that to, but I did\ntake a look at the site, and feel I should warn you - what you\'ve got there is\nmore a heuristic argument explaining why you don\'t expect such a configuration\nto be stable. I do not immediately agree that the conclusion follows from the\nresults you\'ve given. If the claim is true (which it very well may be; I\'m not\nqualified to evaluate it, to be honest), then in order to convince "most\nexperts" you\'re going to need a much more detailed analysis of the situation\nthan that given. That may be just a matter of putting into equations what\nyou\'ve got in words in the paper, but no matter what, you\'ll need something\nmore.\n\n-Eric\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>adul.ahad@ntlworld.com writes:
>
>I have drafted a paper that mathematically demonstrates the physical
>impossibility for a ring system to remain stable around the Earth,
>when hitherto most experts were either unsure or mistakenly believed
>that such a ring system could in fact hold together:-
>
>http://uk.geocities.com/aa_spaceagent/restricted/earth-ring-dynamics.html
>
>My question is which peer reviewed, refereed journal would be a good
>place to send this paper to? I am based in the UK, so would it be
>acceptable in the US astrophysical journal? Is there a Physics journal
>that I can send it to?
>Thanks for all pointers,
>Abdul Ahad
>
I'm not exactly sure which journal to send something like that to, but I did
take a look at the site, and feel I should warn you - what you've got there is
more a heuristic argument explaining why you don't expect such a configuration
to be stable. I do not immediately agree that the conclusion follows from the
results you've given. If the claim is true (which it very well may be; I'm not
qualified to evaluate it, to be honest), then in order to convince "most
experts" you're going to need a much more detailed analysis of the situation
than that given. That may be just a matter of putting into equations what
you've got in words in the paper, but no matter what, you'll need something
more.
-Eric
abdul.ahad@ntlworld.com
Dec8-04, 06:54 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>In my paper, case [1] and [2] are proved beyond all doubt when one\nconsiders simple geocentric orbital motion in 3D. Only case [3] is\n(initially) \'suspect\'.\n\nThe proof of that case is in the *observed* behaviour of geostationary\nsatellites that orbit in the Earth\'s equatorial plane with virtually\nzero degree incline, whose position control thrusters are inoperative.\nAdd to this what is already common knowledge about Laplacian planes, I\nsee further "equation" based proofs as wasting precious time!\n\n"Orbits of uncontrolled GEO objects oscillate around the stable\nLaplacian plane,\nwhich has an inclination of 7.5 =E2=97=A6 with respect to the ..." - resear=\nch\nreference [3] "A Geosynchronous Orbit Search Strategy" - Africano J.;\nSchildknecht T.; Matney M.; Kervin P.; Stansbery E.; Flury W. ,\n2000-01-01\n\nAbove paper on Google listed as an abstract here: -\nhttp://www.google.com/search?hl=3Den&q=3Dafricano+laplacian\n\nIf it isn\'t suitable for any spaceflight journals, then it will (as\nwith all my other *epic* efforts and their world leading conclusions!)\nrespectfully sit in my humble biographical notes:-\n\nhttp://uk.geocities.com/aa_spaceagent/abdul-ahad.html\n\n(Apologies if I sound a bit frustrated... as I am! It\'s hard to get any\nattention from Journal authorities...)\n\ncheers,\n\nAbdul Ahad\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>In my paper, case [1] and [2] are proved beyond all doubt when one
considers simple geocentric orbital motion in 3D. Only case [3] is
(initially) 'suspect'.
The proof of that case is in the *observed* behaviour of geostationary
satellites that orbit in the Earth's equatorial plane with virtually
zero degree incline, whose position control thrusters are inoperative.
Add to this what is already common knowledge about Laplacian planes, I
see further "equation" based proofs as wasting precious time!
"Orbits of uncontrolled GEO objects oscillate around the stable
Laplacian plane,
which has an inclination of 7.5 =E2=97=A6 with respect to the ..." - resear=
ch
reference [3] "A Geosynchronous Orbit Search Strategy" - Africano J.;
Schildknecht T.; Matney M.; Kervin P.; Stansbery E.; Flury W. ,
2000-01-01
Above paper on Google listed as an abstract here: -
http://www.google.com/search?hl=3Den&q=3Dafricano+laplacian
If it isn't suitable for any spaceflight journals, then it will (as
with all my other *epic* efforts and their world leading conclusions!)
respectfully sit in my humble biographical notes:-
http://uk.geocities.com/aa_spaceagent/abdul-ahad.html
(Apologies if I sound a bit frustrated... as I am! It's hard to get any
attention from Journal authorities...)
cheers,
Abdul Ahad
Ralph Hartley
Dec9-04, 02:02 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>abdul.ahad@ntlworld.com wrote:\n> In my paper, case [1] and [2] are proved beyond all doubt when one\n> considers simple geocentric orbital motion in 3D. Only case [3] is\n> (initially) \'suspect\'.\n\nThat isn\'t enough. You need to prove (or at least show) that there aren\'t\nany *other* cases. You haven\'t shown that there can be *no* stable ring in\n*any* orbit.\n\n> "Orbits of uncontrolled GEO objects oscillate around the stable\n> Laplacian plane,\n> which has an inclination of 7.5 =E2=97=A6 with respect to the ..." - resear=\n> ch\n> reference [3] "A Geosynchronous Orbit Search Strategy" - Africano J.;\n> Schildknecht T.; Matney M.; Kervin P.; Stansbery E.; Flury W. ,\n> 2000-01-01\n>\n> Above paper on Google listed as an abstract here: -\n> http://www.google.com/search?hl=3Den&q=3Dafricano+laplacian\n\nThe way I read this leaves open the possibility that your conclusion is\nincorrect.\n\nNote the phrase "the stable Laplacian plane". The implication is that a\nring in *that* plane, not the planes you looked at, might be stable. I\ndon\'t know for sure if that is so, but it wouldn\'t surprise me.\n\nIt looks like a set of particles released in a single oscillating plane\nwould continue to oscillate together, producing a ring that wobbles, but\ndoes not spread. (Old geosynchronous satellites aren\'t like that, because\nthey are all released at different times.)\n\nAs for your underlying question, "would it pose an unacceptable hazard to\nnavigation?" I suspect that, unless it was *extremely* narrow, even a\ncompletely stable ring would be unacceptable.\n\nRemember that every orbit must pass through the ring plane twice in each\nrevolution. To be safe, each of those crossings must be either inside or\noutside the ring. That completely rules out circular orbits with the same\nperiod as the ring.\n\nAlso, it would be incompatible with low thrust propulsion, such as solar\nsails and ion drives. To pass the ring, any spacecraft would have to raise\n(or lower) its apogee by at least the thickness of the ring within one\norbit. That would put an absolute lower limit on the thrust to mass ratio\nof all spacecraft passing the ring.\n\nRalph Hartley\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>abdul.ahad@ntlworld.com wrote:
> In my paper, case [1] and [2] are proved beyond all doubt when one
> considers simple geocentric orbital motion in 3D. Only case [3] is
> (initially) 'suspect'.
That isn't enough. You need to prove (or at least show) that there aren't
any *other* cases. You haven't shown that there can be *no* stable ring in
*any* orbit.
> "Orbits of uncontrolled GEO objects oscillate around the stable
> Laplacian plane,
> which has an inclination of 7.5 =E2=97=A6 with respect to the ..." - resear=
> ch
> reference [3] "A Geosynchronous Orbit Search Strategy" - Africano J.;
> Schildknecht T.; Matney M.; Kervin P.; Stansbery E.; Flury W. ,
> 2000-01-01
>
> Above paper on Google listed as an abstract here: -
> http://www.google.com/search?hl=3Den&q=3Dafricano+laplacian
The way I read this leaves open the possibility that your conclusion is
incorrect.
Note the phrase "the stable Laplacian plane". The implication is that a
ring in *that* plane, not the planes you looked at, might be stable. I
don't know for sure if that is so, but it wouldn't surprise me.
It looks like a set of particles released in a single oscillating plane
would continue to oscillate together, producing a ring that wobbles, but
does not spread. (Old geosynchronous satellites aren't like that, because
they are all released at different times.)
As for your underlying question, "would it pose an unacceptable hazard to
navigation?" I suspect that, unless it was *extremely* narrow, even a
completely stable ring would be unacceptable.
Remember that every orbit must pass through the ring plane twice in each
revolution. To be safe, each of those crossings must be either inside or
outside the ring. That completely rules out circular orbits with the same
period as the ring.
Also, it would be incompatible with low thrust propulsion, such as solar
sails and ion drives. To pass the ring, any spacecraft would have to raise
(or lower) its apogee by at least the thickness of the ring within one
orbit. That would put an absolute lower limit on the thrust to mass ratio
of all spacecraft passing the ring.
Ralph Hartley
Kris Kennaway
Dec9-04, 11:33 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\nOn 2004-12-08, abdul.ahad@ntlworld.com <abdul.ahad@ntlworld.com> wrote:\n\n> If it isn\'t suitable for any spaceflight journals, then it will (as\n> with all my other *epic* efforts and their world leading conclusions!)\n> respectfully sit in my humble biographical notes:-\n>\n> http://uk.geocities.com/aa_spaceagent/abdul-ahad.html\n>\n> (Apologies if I sound a bit frustrated... as I am! It\'s hard to get any\n> attention from Journal authorities...)\n\nDoing research involves being receptive to feedback, in particular\nthey tell you your work is lacking and how you can improve it.\n\nIf you can swallow your pride and take the advice in hand, maybe\nyou\'ll be able to produce something people will be interested in\nreading.\n\nIf not, then best of luck with your future "epic efforts". At least\nthere\'ll be one person who will be impressed by them :-)\n\nKris\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>On 2004-12-08, abdul.ahad@ntlworld.com <abdul.ahad@ntlworld.com> wrote:
> If it isn't suitable for any spaceflight journals, then it will (as
> with all my other *epic* efforts and their world leading conclusions!)
> respectfully sit in my humble biographical notes:-
>
> http://uk.geocities.com/aa_spaceagent/abdul-ahad.html
>
> (Apologies if I sound a bit frustrated... as I am! It's hard to get any
> attention from Journal authorities...)
Doing research involves being receptive to feedback, in particular
they tell you your work is lacking and how you can improve it.
If you can swallow your pride and take the advice in hand, maybe
you'll be able to produce something people will be interested in
reading.
If not, then best of luck with your future "epic efforts". At least
there'll be one person who will be impressed by them :-)
Kris
abdul.ahad@ntlworld.com
Dec10-04, 05:01 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Ralph Hartley wrote:\n> abdul.ahad@ntlworld.com wrote:\n> > In my paper, case [1] and [2] are proved beyond all doubt when one\n> > considers simple geocentric orbital motion in 3D. Only case [3] is\n> > (initially) \'suspect\'.\n>\n> That isn\'t enough. You need to prove (or at least show) that there\naren\'t\n> any *other* cases. You haven\'t shown that there can be *no* stable\nring in\n> *any* orbit.\n\nYes you\'re quite right here, I have only picked a few "example"\norientations to computationally show the instability. There are a\ncouple of scenarios where, unless one plugs in some numbers and does\nthe sums, one may be mistaken into thinking there\'s some room for a\nstable ring. First is where the inclination i=63.5 degrees, where by\nequation (2) the term (2 - 5/2 * sin^2 i) would equal zero. So for even\nan elliptical ring system at that inclination, the line of apsides\nwould not precess at all. However, by equation (1) an inclination of\ni=63.5 degrees would still precess the line of nodes, since the term in\ncos(i) still has a value, and the rates of precession for an outer\nversus inner ring particle (P1 and P2 as per my existing nomenclature\nin the given diagrams) would be different. So ring system not stable.\n\nI have just noticed that a perfectly polar ring system would be a\nspecial case. So I have inserted this as an addendum to case [1]:\n\n"By equations (1) and (2) above, there is one unique case where a ring\nsystem *could* theoretically hold stable: where the inclination, i=90\ndegrees (exactly polar) and the eccentricity, e=0 (exactly circular).\nThat orientation would however cause the ring plane to experience\nmaximum solar light pressure (if oriented face on relative to the Sun)\nand the stipulation here is based on only a *first order* dynamical\nmodel that ignores perturbative influences from the Sun and the Moon."\n\n>\n> > "Orbits of uncontrolled GEO objects oscillate around the stable\n> > Laplacian plane,\n> > which has an inclination of 7.5 =E2=97=A6 with respect to the ..."\n- resear=\n> > ch\n> > reference [3] "A Geosynchronous Orbit Search Strategy" - Africano\nJ.;\n> > Schildknecht T.; Matney M.; Kervin P.; Stansbery E.; Flury W. ,\n> > 2000-01-01\n> >\n> > Above paper on Google listed as an abstract here: -\n> > http://www.google.com/search?hl=3Den&q=3Dafricano+laplacian\n>\n> The way I read this leaves open the possibility that your conclusion\nis\n> incorrect.\n>\n> Note the phrase "the stable Laplacian plane". The implication is that\na\n> ring in *that* plane, not the planes you looked at, might be stable.\nI\n> don\'t know for sure if that is so, but it wouldn\'t surprise me.\n\nThe Laplacian plane is an instantaneous *average* that passes through\nthe "invariable" momentum plane of the Earth-Moon-Sun gravity force, so\nis constantly shifting relative to the Earth\'s equatorial plane, as the\nMoon and Sun change orientation. I think it is also affected by changes\nin the Earth-Moon barycentre (center of mass) as the Moon revolves\naround the Earth every 27 days.\n\nSo I don\'t accept the Laplacian plane to be "fixed" relative to\nanything. The Earth goes around the Sun, the Moon goes around the\nEarth, all the planes are inclined at various angles to each other and\nare in constant motion.\n\nIf the ring system is at a "fixed" inclination relative to the Earth\'s\nequator, it cannot be then said to be at a "fixed" inclination relative\nto the Laplacian plane... the two are rotating (precessing) all the\ntime.\n\n>\n> It looks like a set of particles released in a single oscillating\nplane\n> would continue to oscillate together, producing a ring that wobbles,\nbut\n> does not spread. (Old geosynchronous satellites aren\'t like that,\nbecause\n> they are all released at different times.)\n\nConsider that the ring has finite *width* where the inner and the outer\nparticles of the ring are spaced apart and have differentially\nprecessing orbits with respect to their lines of *nodes* and *apsides*.\n\n>\n> As for your underlying question, "would it pose an unacceptable hazard to\n> navigation?" I suspect that, unless it was *extremely* narrow, even a\n\n> completely stable ring would be unacceptable.\n>\n> Remember that every orbit must pass through the ring plane twice in each\n> revolution. To be safe, each of those crossings must be either inside or\n> outside the ring. That completely rules out circular orbits with the same\n> period as the ring.\n>\n> Also, it would be incompatible with low thrust propulsion, such as solar\n> sails and ion drives. To pass the ring, any spacecraft would have to raise\n> (or lower) its apogee by at least the thickness of the ring within one\n> orbit. That would put an absolute lower limit on the thrust to mass ratio\n> of all spacecraft passing the ring.\n>\n> Ralph Hartley\n\nThe overall conclusion seems to be that, with the greatest of respect\nfor their work, those guys who produced that Sandia National\nLaboratories research article about possible climate change due to\nEarth rings were likely to have been flawed in their opinion. The Earth\ncannot maintain a stable ring system and all future orbital engineering\nprojects will need to be mindful of how they scatter unwanted debris\naround the planet, \'cos they aint gonna be contained in a neat ring\nplane - fact!\n\nAbdul Ahad\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>Ralph Hartley wrote:
> abdul.ahad@ntlworld.com wrote:
> > In my paper, case [1] and [2] are proved beyond all doubt when one
> > considers simple geocentric orbital motion in 3D. Only case [3] is
> > (initially) 'suspect'.
>
> That isn't enough. You need to prove (or at least show) that there
aren't
> any *other* cases. You haven't shown that there can be *no* stable
ring in
> *any* orbit.
Yes you're quite right here, I have only picked a few "example"
orientations to computationally show the instability. There are a
couple of scenarios where, unless one plugs in some numbers and does
the sums, one may be mistaken into thinking there's some room for a
stable ring. First is where the inclination i=63.5 degrees, where by
equation (2) the term (2 - 5/2 * sin^2 i) would equal zero. So for even
an elliptical ring system at that inclination, the line of apsides
would not precess at all. However, by equation (1) an inclination of
i=63.5 degrees would still precess the line of nodes, since the term in
cos(i) still has a value, and the rates of precession for an outer
versus inner ring particle (P1 and P2 as per my existing nomenclature
in the given diagrams) would be different. So ring system not stable.
I have just noticed that a perfectly polar ring system would be a
special case. So I have inserted this as an addendum to case [1]:
"By equations (1) and (2) above, there is one unique case where a ring
system *could* theoretically hold stable: where the inclination, i=90
degrees (exactly polar) and the eccentricity, e=0 (exactly circular).
That orientation would however cause the ring plane to experience
maximum solar light pressure (if oriented face on relative to the Sun)
and the stipulation here is based on only a *first order* dynamical
model that ignores perturbative influences from the Sun and the Moon."
>
> > "Orbits of uncontrolled GEO objects oscillate around the stable
> > Laplacian plane,
> > which has an inclination of 7.5 =E2=97=A6 with respect to the ..."
- resear=
> > ch
> > reference [3] "A Geosynchronous Orbit Search Strategy" - Africano
J.;
> > Schildknecht T.; Matney M.; Kervin P.; Stansbery E.; Flury W. ,
> > 2000-01-01
> >
> > Above paper on Google listed as an abstract here: -
> > http://www.google.com/search?hl=3Den&q=3Dafricano+laplacian
>
> The way I read this leaves open the possibility that your conclusion
is
> incorrect.
>
> Note the phrase "the stable Laplacian plane". The implication is that
a
> ring in *that* plane, not the planes you looked at, might be stable.
I
> don't know for sure if that is so, but it wouldn't surprise me.
The Laplacian plane is an instantaneous *average* that passes through
the "invariable" momentum plane of the Earth-Moon-Sun gravity force, so
is constantly shifting relative to the Earth's equatorial plane, as the
Moon and Sun change orientation. I think it is also affected by changes
in the Earth-Moon barycentre (center of mass) as the Moon revolves
around the Earth every 27 days.
So I don't accept the Laplacian plane to be "fixed" relative to
anything. The Earth goes around the Sun, the Moon goes around the
Earth, all the planes are inclined at various angles to each other and
are in constant motion.
If the ring system is at a "fixed" inclination relative to the Earth's
equator, it cannot be then said to be at a "fixed" inclination relative
to the Laplacian plane... the two are rotating (precessing) all the
time.
>
> It looks like a set of particles released in a single oscillating
plane
> would continue to oscillate together, producing a ring that wobbles,
but
> does not spread. (Old geosynchronous satellites aren't like that,
because
> they are all released at different times.)
Consider that the ring has finite *width* where the inner and the outer
particles of the ring are spaced apart and have differentially
precessing orbits with respect to their lines of *nodes* and *apsides*.
>
> As for your underlying question, "would it pose an unacceptable hazard to
> navigation?" I suspect that, unless it was *extremely* narrow, even a
> completely stable ring would be unacceptable.
>
> Remember that every orbit must pass through the ring plane twice in each
> revolution. To be safe, each of those crossings must be either inside or
> outside the ring. That completely rules out circular orbits with the same
> period as the ring.
>
> Also, it would be incompatible with low thrust propulsion, such as solar
> sails and ion drives. To pass the ring, any spacecraft would have to raise
> (or lower) its apogee by at least the thickness of the ring within one
> orbit. That would put an absolute lower limit on the thrust to mass ratio
> of all spacecraft passing the ring.
>
> Ralph Hartley
The overall conclusion seems to be that, with the greatest of respect
for their work, those guys who produced that Sandia National
Laboratories research article about possible climate change due to
Earth rings were likely to have been flawed in their opinion. The Earth
cannot maintain a stable ring system and all future orbital engineering
projects will need to be mindful of how they scatter unwanted debris
around the planet, 'cos they aint gonna be contained in a neat ring
plane - fact!
Abdul Ahad
Kris Kennaway
Dec10-04, 10:18 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nOn 2004-12-09, Kris Kennaway <kkenn@xor.obsecurity.org> wrote:\n>\n>\n>\n> On 2004-12-08, abdul.ahad@ntlworld.com <abdul.ahad@ntlworld.com> wrote:\n>\n>> If it isn\'t suitable for any spaceflight journals, then it will (as\n>> with all my other *epic* efforts and their world leading conclusions!)\n>> respectfully sit in my humble biographical notes:-\n>>\n>> http://uk.geocities.com/aa_spaceagent/abdul-ahad.html\n>>\n>> (Apologies if I sound a bit frustrated... as I am! It\'s hard to get any\n>> attention from Journal authorities...)\n\nThis message seems to have been corrupted in transit. What I actually\nsais was:\n\n> Doing research involves being receptive to feedback, in particular\n\nwhen\n\n> they tell you your work is lacking and how you can improve it.\n\nKris\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>On 2004-12-09, Kris Kennaway <kkenn@xor.obsecurity.org> wrote:
>
>
>
> On 2004-12-08, abdul.ahad@ntlworld.com <abdul.ahad@ntlworld.com> wrote:
>
>> If it isn't suitable for any spaceflight journals, then it will (as
>> with all my other *epic* efforts and their world leading conclusions!)
>> respectfully sit in my humble biographical notes:-
>>
>> http://uk.geocities.com/aa_spaceagent/abdul-ahad.html
>>
>> (Apologies if I sound a bit frustrated... as I am! It's hard to get any
>> attention from Journal authorities...)
This message seems to have been corrupted in transit. What I actually
sais was:
> Doing research involves being receptive to feedback, in particular
when
> they tell you your work is lacking and how you can improve it.
Kris
Kris Kennaway
Dec13-04, 11:29 PM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>loyal primarily to one another rather\nthan to the system, hence the system cannot control them. Or take the\ngypsies. The gypsies commonly get away with theft and fraud because\ntheir loyalties are such that they can always get other gypsies to\ngive testimony that "proves" their innocence. Obviously the system\nwould be in serious trouble if too many people belonged to such\ngroups. Some of the early-20th century Chinese thinkers who were\nconcerned with modernizing China recognized the necessity of breaking\ndown small-scale social groups such as the family: "(According to Sun\nYat-sen) The Chinese people needed a new surge of patriotism, which\nwould lead to a transfer of loyalty from the family to the state. .\n.(According to Li Huang) traditional attachments, particularly to the\nfamily had to be abandoned if nationalism were to develop to China."\n(Chester C. Tan, Chinese Political Thought in the Twentieth Century,"\npage 125, page 297.)\n\n8. (Paragraph 56) Yes, we know that 19th century America had its\nproblems, and serious ones, but for the sake of breviety we have to\nexpress ourselves in simplified terms.\n\n9. (Paragraph 61) We leave aside the underclass. We are speaking of\nthe mainstream.\n\n10. (Paragraph 62) Some social scientists, educators, "mental health"\nprofessionals and the like are doing their best to push the social\ndrives into group 1 by trying to see to it that everyone has a\nsatisfactory social life.\n\n11. (Paragraphs 63, 82) Is the drive for endless material acquisition\nreally an artificial creation of the advertising and marketing\nindustry? Certainly there is no innate human drive for material\nacquisition. There have been many cultures in which people have\ndesired little material wealth beyond what was ne\n\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>loyal primarily to one another rather
than to the system, hence the system cannot control them. Or take the
gypsies. The gypsies commonly get away with theft and fraud because
their loyalties are such that they can always get other gypsies to
give testimony that "proves" their innocence. Obviously the system
would be in serious trouble if too many people belonged to such
groups. Some of the early-20th century Chinese thinkers who were
concerned with modernizing China recognized the necessity of breaking
down small-scale social groups such as the family: "(According to Sun
Yat-sen) The Chinese people needed a new surge of patriotism, which
would lead to a transfer of loyalty from the family to the state. .
.(According to Li Huang) traditional attachments, particularly to the
family had to be abandoned if nationalism were to develop to China."
(Chester C. Tan, Chinese Political Thought in the Twentieth Century,"
page 125, page 297.)
8. (Paragraph 56) Yes, we know that 19th century America had its
problems, and serious ones, but for the sake of breviety we have to
express ourselves in simplified terms.
9. (Paragraph 61) We leave aside the underclass. We are speaking of
the mainstream.
10. (Paragraph 62) Some social scientists, educators, "mental health"
professionals and the like are doing their best to push the social
drives into group 1 by trying to see to it that everyone has a
satisfactory social life.
11. (Paragraphs 63, 82) Is the drive for endless material acquisition
really an artificial creation of the advertising and marketing
industry? Certainly there is no innate human drive for material
acquisition. There have been many cultures in which people have
desired little material wealth beyond what was ne
Ralph Hartley
Dec14-04, 10:18 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\nabdul.ahad@ntlworld.com wrote:\n> Ralph Hartley wrote:\n\n>>Note the phrase "the stable Laplacian plane". The implication is that\n>>a ring in *that* plane, not the planes you looked at, might be stable.\n>\n> The Laplacian plane is an instantaneous *average* that passes through\n> the "invariable" momentum plane of the Earth-Moon-Sun gravity force, so\n> is constantly shifting relative to the Earth\'s equatorial plane, as the\n> Moon and Sun change orientation.\n\nFrom what I\'m reading, it is a fixed plane, at least on human timescales.\nIt depends on the equator, the plane of motion of the moon, and the plane\nof the earth\'s orbit, all of which are fixed. (They do change over\nthousands of years)\n\nGeostationary satellites wobble around that plane with a period of ~50\nyears, so it can\'t be something that changes from month to month.\n\n> So I don\'t accept the Laplacian plane to be "fixed" relative to\n> anything. The Earth goes around the Sun, the Moon goes around the\n> Earth, all the planes are inclined at various angles to each other and\n> are in constant motion.\n\nIt is fixed, as it is defined, relative to the equator, in coordinates that\nmove with the earth.\n\n> Consider that the ring has finite *width* where the inner and the outer\n> particles of the ring are spaced apart and have differentially\n> precessing orbits with respect to their lines of *nodes* and *apsides*.\n\nIt is true that the Laplacian plane is a function of orbital radius, so a\nthick ring is much more complicated.\n\nI do not pretend to know under what conditions a stable planetary ring can\nexist. It would surprise me if the general answer were known, and not\nbecause people haven\'t tried.\n\nYou haven\'t even touched the really tricky part, the effect of collisions\nbetween ring particles.\n\nRalph Hartley\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>abdul.ahad@ntlworld.com wrote:
> Ralph Hartley wrote:
>>Note the phrase "the stable Laplacian plane". The implication is that
>>a ring in *that* plane, not the planes you looked at, might be stable.
>
> The Laplacian plane is an instantaneous *average* that passes through
> the "invariable" momentum plane of the Earth-Moon-Sun gravity force, so
> is constantly shifting relative to the Earth's equatorial plane, as the
> Moon and Sun change orientation.
From what I'm reading, it is a fixed plane, at least on human timescales.
It depends on the equator, the plane of motion of the moon, and the plane
of the earth's orbit, all of which are fixed. (They do change over
thousands of years)
Geostationary satellites wobble around that plane with a period of ~50
years, so it can't be something that changes from month to month.
> So I don't accept the Laplacian plane to be "fixed" relative to
> anything. The Earth goes around the Sun, the Moon goes around the
> Earth, all the planes are inclined at various angles to each other and
> are in constant motion.
It is fixed, as it is defined, relative to the equator, in coordinates that
move with the earth.
> Consider that the ring has finite *width* where the inner and the outer
> particles of the ring are spaced apart and have differentially
> precessing orbits with respect to their lines of *nodes* and *apsides*.
It is true that the Laplacian plane is a function of orbital radius, so a
thick ring is much more complicated.
I do not pretend to know under what conditions a stable planetary ring can
exist. It would surprise me if the general answer were known, and not
because people haven't tried.
You haven't even touched the really tricky part, the effect of collisions
between ring particles.
Ralph Hartley
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