Asrophysics Orbit of Sun Barycenter [Archive]

Erhard Borcke

Jun11-04, 07:29 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>\nHello, who likes to discuss with me backgrounds to the following keywords:\n\nSunorbit - Speed and Distance to CM - Angularmomentum L -\nTorque T - Cycles of L or T with time - Perturbation of earthorbit,\n\nspecially in astrophysical aspects.\n\nLet\'s start with the qestion: Is the sun or the CM the point of\nrotation for the orbit of earth?\n\n\n[Moderator\'s note: Message reformatted for readability by moderator.\n-usc]\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>Hello, who likes to discuss with me backgrounds to the following keywords:

Sunorbit - Speed and Distance to CM - Angularmomentum L -
Torque T - Cycles of L or T with time - Perturbation of earthorbit,

specially in astrophysical aspects.

Let's start with the qestion: Is the sun or the CM the point of
rotation for the orbit of earth?

[Moderator's note: Message reformatted for readability by moderator.
-usc]

Mark Palenik

Jun12-04, 08:21 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>"Erhard Borcke" <ge62@freenet.de> wrote in message\nnews:452d0bc4.0406100437.60e21dad@posting .google.com...\n>\n> Hello, who likes to discuss with me backgrounds to the following keywords:\n>\n> Sunorbit - Speed and Distance to CM - Angularmomentum L -\n> Torque T - Cycles of L or T with time - Perturbation of earthorbit,\n>\n> specially in astrophysical aspects.\n>\n> Let\'s start with the qestion: Is the sun or the CM the point of\n> rotation for the orbit of earth?\n>\n>\n> [Moderator\'s note: Message reformatted for readability by moderator.\n> -usc]\n\nThe center of mass should be the point of rotation, but don\'t forget, you\nhave 8 other planets as well.\n\nI think that even with the great distance between the earth and the sun, the\ncenter of mass is still very close to the center of the sun, comparatively -\nand with the 8 other planets in there, using the center of mass of the\nsun/earth as your point of rotation may not really be a better\napproximation. Besides, how accurately do you know the distance to the sun,\nanyway?\n\nSpeed and distance to CM are fairly self explanitory\nAngular momentum, L is m*r^2*theta_dot (the derivitave of the angular\ncoordinate)\nI\'m not completely sure that you need torque to solve this problem, but it\'s\nRxF\n\nAs for perturbations, I think whatever you got that from is probably\nreferring to small perturbations in the earth\'s orbit, like if you gave it a\nlittle push away from the sun, and it osciallated back and forth. If you\nneed to find the frequency of these perturbations, you can approximate the\nsystem as a harmonic oscillator through a taylor series expansion, since\nthese perturbations should be fairly small.\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>"Erhard Borcke" <ge62@freenet.de> wrote in message
news:452d0bc4.0406100437.60e21dad@posting.google.c om...
>
> Hello, who likes to discuss with me backgrounds to the following keywords:
>
> Sunorbit - Speed and Distance to CM - Angularmomentum L -
> Torque T - Cycles of L or T with time - Perturbation of earthorbit,
>
> specially in astrophysical aspects.
>
> Let's start with the qestion: Is the sun or the CM the point of
> rotation for the orbit of earth?
>
>
> [Moderator's note: Message reformatted for readability by moderator.
> -usc]

The center of mass should be the point of rotation, but don't forget, you
have 8 other planets as well.

I think that even with the great distance between the earth and the sun, the
center of mass is still very close to the center of the sun, comparatively -
and with the 8 other planets in there, using the center of mass of the
sun/earth as your point of rotation may not really be a better
approximation. Besides, how accurately do you know the distance to the sun,
anyway?

Speed and distance to CM are fairly self explanitory
Angular momentum, L is m*r^2*\theta_dot (the derivitave of the angular
coordinate)
I'm not completely sure that you need torque to solve this problem, but it's
RxF

As for perturbations, I think whatever you got that from is probably
referring to small perturbations in the earth's orbit, like if you gave it a
little push away from the sun, and it osciallated back and forth. If you
need to find the frequency of these perturbations, you can approximate the
system as a harmonic oscillator through a taylor series expansion, since
these perturbations should be fairly small.

Erhard Borcke

Jun14-04, 04:11 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>Mark, thank you for your reaction. My existing material are curves of\nangular momentum L over 6 millenniums, made from values of speed and\ndistance of the sun to CM. The value is ca. 25% of the L from rotation\nand the variation from mean is factor 2. My final aim is to detect,\nwhere the existing differences of L will be found elsewhere. Up to\nnow, it is not clear to me, if there will be an transport of L from L\nof the sun to earths orbit.\nThe distance of sun from CM is periodically between 10^7 and 10^9 m\nand I am really interested, if this difference brings a perturbation\nto earths orbit and to estimate the amount of it.\nMy proposal is, to discuss all step by step, beginning with : What is\nthe point of rotation of earths orbit, because even under experts\nthere is no agreement about this, p.e. in the paper of Freemann and\nHasling http://www.zjcJ:ams.confex.com/ams/pdfpapers/51139.pdf+Freeman+Hasling+orbital+motion&hl=de&ie=UTF-8\n\n.. I think, the consequense is, if the sun itself is the point of\nrotation, there could not be a perturbation from the sun.\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>Mark, thank you for your reaction. My existing material are curves of
angular momentum L over 6 millenniums, made from values of speed and
distance of the sun to CM. The value is ca. 25% of the L from rotation
and the variation from mean is factor 2. My final aim is to detect,
where the existing differences of L will be found elsewhere. Up to
now, it is not clear to me, if there will be an transport of L from L
of the sun to earths orbit.
The distance of sun from CM is periodically between 10^7 and 10^9 m
and I am really interested, if this difference brings a perturbation
to earths orbit and to estimate the amount of it.
My proposal is, to discuss all step by step, beginning with : What is
the point of rotation of earths orbit, because even under experts
there is no agreement about this, p.e. in the paper of Freemann and
Hasling http://www.zjcJ:ams.confex.com/ams/pdfpapers/51139.pdf+Freeman+Hasling+orbital+motion&hl=de&ie=UTF-8

.. I think, the consequense is, if the sun itself is the point of
rotation, there could not be a perturbation from the sun.