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Chalky
Mar 11, 2012, 12:26:33 PM3/11/12
to
On Mar 11, 6:02 am, Tom Roberts <tjroberts...@sbcglobal.net> wrote (at
spf):
> On 3/10/12 3/10/12 4:21 PM, Chalky wrote at spf:
>
> > If what you say is true, and any inverse square law would be too
> > inaccurate to use, even for light, in a flat spacetime, how come such
> > an inverse square law can be, and is still, invariably used for
> > gravity, to compute the orbits of the outer planets of our own solar
> > system, with sufficient accuracy to satisfy astronomers?
[snip]
> (For computing detailed orbits, to the accuracy of measurements
> such as the perihelion shifts of planets, GR is required.)
You are mistaken, in the quoted context of the outer planets. I
suggest you peruse a copy of the
ASTRONOMICAL PAPERS of the AMERICAN EPHEMERIS AND NAUTICAL ALMANAC
Vol XII Coordinates of the Five Outer Planets
....paying particular attention to the introduction, and observation
residuals.
(I got my copy at the astronomy library of Cambridge University when I
was there, but I guess most good university astronomy libraries will
have one in use.)
> Astronomers and astrophysicists know all about this, and routinely correct their
> measurements for these effects.
Again, you are mistaken, in the quoted context (see above).
In fact, the only examples of GR being used for outer solar system
computations (that I have come across), are found in the papers on the
Pioneer anomalies.
Here, Anderson et al. specifically state that GR corrections have
additionally been used.
Having said that, this is precisely where anomalies have been
observed.
This leads me to wonder what GR corrections, precisely, they did use.
Did they, for example, conclude Pioneers were not, ultimately,
gravitationally bound, by design, thus making cosmological redshift
adjustments potentially prudent.
I cannot ask Anderson myself, because the arXiv does not currently
allow me access to his email address (or phone number either, for that
matter).
spf):
> On 3/10/12 3/10/12 4:21 PM, Chalky wrote at spf:
>
> > If what you say is true, and any inverse square law would be too
> > inaccurate to use, even for light, in a flat spacetime, how come such
> > an inverse square law can be, and is still, invariably used for
> > gravity, to compute the orbits of the outer planets of our own solar
> > system, with sufficient accuracy to satisfy astronomers?
[snip]
> (For computing detailed orbits, to the accuracy of measurements
> such as the perihelion shifts of planets, GR is required.)
You are mistaken, in the quoted context of the outer planets. I
suggest you peruse a copy of the
ASTRONOMICAL PAPERS of the AMERICAN EPHEMERIS AND NAUTICAL ALMANAC
Vol XII Coordinates of the Five Outer Planets
....paying particular attention to the introduction, and observation
residuals.
(I got my copy at the astronomy library of Cambridge University when I
was there, but I guess most good university astronomy libraries will
have one in use.)
> Astronomers and astrophysicists know all about this, and routinely correct their
> measurements for these effects.
Again, you are mistaken, in the quoted context (see above).
In fact, the only examples of GR being used for outer solar system
computations (that I have come across), are found in the papers on the
Pioneer anomalies.
Here, Anderson et al. specifically state that GR corrections have
additionally been used.
Having said that, this is precisely where anomalies have been
observed.
This leads me to wonder what GR corrections, precisely, they did use.
Did they, for example, conclude Pioneers were not, ultimately,
gravitationally bound, by design, thus making cosmological redshift
adjustments potentially prudent.
I cannot ask Anderson myself, because the arXiv does not currently
allow me access to his email address (or phone number either, for that
matter).
eric gisse
Mar 11, 2012, 9:16:07 PM3/11/12
to
Chalky <chalk...@bleachboys.co.uk> wrote in
news:62b2b273-4e7a-4474...@j5g2000yqm.googlegroups.com:
[...]
> This leads me to wonder what GR corrections, precisely, they did use.
Reading the paper and references discussing planetary epheremis
calculations would be instructive, I would imagine.
>
> Did they, for example, conclude Pioneers were not, ultimately,
> gravitationally bound, by design, thus making cosmological redshift
> adjustments potentially prudent.
Cosmology has nothing to do with this.
Relativistic corrections include time dilation, doppler shift, etc which
does not include non-relativistic stuff like dust, thermal emissions,
etc.
www.google.com "planetary epheremis relativistic" 678,000 hits
First result: "Relativistic aspects of the JPL planetary ephemeris"
journals.cambridge.org/article_S1743921309990329
[[Mod. note -- It's open-access, too! -- jt]]
news:62b2b273-4e7a-4474...@j5g2000yqm.googlegroups.com:
[...]
> This leads me to wonder what GR corrections, precisely, they did use.
calculations would be instructive, I would imagine.
>
> Did they, for example, conclude Pioneers were not, ultimately,
> gravitationally bound, by design, thus making cosmological redshift
> adjustments potentially prudent.
Relativistic corrections include time dilation, doppler shift, etc which
does not include non-relativistic stuff like dust, thermal emissions,
etc.
www.google.com "planetary epheremis relativistic" 678,000 hits
First result: "Relativistic aspects of the JPL planetary ephemeris"
journals.cambridge.org/article_S1743921309990329
[[Mod. note -- It's open-access, too! -- jt]]
Chalky
Mar 12, 2012, 4:30:29 AM3/12/12
to
On Mar 11, 4:26=A0pm, Chalky <chalkys...@bleachboys.co.uk> wrote:
> On Mar 11, 6:02 am, Tom Roberts <tjroberts...@sbcglobal.net> wrote (at
> spf):
>
> > On 3/10/12 3/10/12 =A0 4:21 PM, Chalky wrote at spf:
> On Mar 11, 6:02 am, Tom Roberts <tjroberts...@sbcglobal.net> wrote (at
> spf):
>
>
> > > If what you say is true, and any inverse square law would be too
> > > inaccurate to use, even for light, in a flat spacetime, how come such
> > > an inverse square law can be, and is still, invariably used for
> > > gravity, to compute the orbits of the outer planets of our own solar
> > > system, with sufficient accuracy to satisfy astronomers?
>
> [snip]
>
> > =A0 =A0 =A0 =A0 (For computing detailed orbits, to the accuracy of meas=
> > > If what you say is true, and any inverse square law would be too
> > > inaccurate to use, even for light, in a flat spacetime, how come such
> > > an inverse square law can be, and is still, invariably used for
> > > gravity, to compute the orbits of the outer planets of our own solar
> > > system, with sufficient accuracy to satisfy astronomers?
>
> [snip]
>
urements
> > =A0 =A0 =A0 =A0 =A0such as the perihelion shifts of planets, GR is requ=
ired.)
>
> You are mistaken, in the quoted context of the outer planets. I
> suggest you peruse a copy of the
>
> ASTRONOMICAL PAPERS of the AMERICAN =A0EPHEMERIS AND NAUTICAL ALMANAC
>
> You are mistaken, in the quoted context of the outer planets. I
> suggest you peruse a copy of the
>
> Vol XII =A0 =A0 =A0Coordinates of the Five Outer Planets
>
> ....paying particular attention to the introduction, and observation
> residuals.
>
> (I got my copy at the astronomy library of Cambridge University when I
> was there, but I guess most good university astronomy libraries will
> have one in use.)
>
> > Astronomers and astrophysicists know all about this, and routinely corr=
> ....paying particular attention to the introduction, and observation
> residuals.
>
> (I got my copy at the astronomy library of Cambridge University when I
> was there, but I guess most good university astronomy libraries will
> have one in use.)
>
ect their
> > measurements for these effects.
>
> Again, you are mistaken, in the quoted context (see above).
>
> In fact, the only examples of GR being used for outer solar system
> computations (that I have come across), are found in the papers on the
> Pioneer anomalies.
>
> Here, Anderson et al. specifically state that GR corrections have
> additionally been used.
>
> Having said that, this is precisely where
The word PERSISTENT should have been included at this exact spot
> > measurements for these effects.
>
> Again, you are mistaken, in the quoted context (see above).
>
> In fact, the only examples of GR being used for outer solar system
> computations (that I have come across), are found in the papers on the
> Pioneer anomalies.
>
> Here, Anderson et al. specifically state that GR corrections have
> additionally been used.
>
> Having said that, this is precisely where
>anomalies have been
> observed.
>
> This leads me to wonder what GR corrections, precisely, they did use.
>
> Did they, for example, conclude Pioneers were not, ultimately,
> gravitationally bound, by design, thus making cosmological redshift
> adjustments potentially prudent.
Presumably, bot the navigation and tracking software would have been
completed and debugged before both Pioneers 10 and 11 were launched,
thus leaving Anderson et al. to do nothing more than investigate the
resultant persistent anomaly.
Jonathan Thornburg [remove -animal to reply]
Mar 12, 2012, 4:30:31 AM3/12/12
to
Chalky <chalk...@bleachboys.co.uk> wrote:
> the only examples of GR being used for outer solar system
> computations (that I have come across), are found in the papers on the
> Pioneer anomalies.
>
> Here, Anderson et al. specifically state that GR corrections have
> additionally been used.
>
> Having said that, this is precisely where anomalies have been
> observed.
>
> This leads me to wonder what GR corrections, precisely, they did use.
According to page 3 of
> the only examples of GR being used for outer solar system
> computations (that I have come across), are found in the papers on the
> Pioneer anomalies.
>
> Here, Anderson et al. specifically state that GR corrections have
> additionally been used.
>
> Having said that, this is precisely where anomalies have been
> observed.
>
> This leads me to wonder what GR corrections, precisely, they did use.
Folkner, Williams, and Boggs,
"The Planetary and Lunar Ephemeris DE 421"
IPN Progress Report 42-178 ? August 15, 2009
http://tmo.jpl.nasa.gov/progress_report/42-178/178C.pdf
"For DE 421, the positions of the Moon and planets were integrated using
an n-body parameterized post-Newtonian (PPN) metric [5,6,4]."
The table later on that page includes both the inner *and the outer planets*.
The cited references are
[4] T. D. Moyer, Formulation for Observed and Computed Values of Deep Space
Network Data Types for Navigation, Monograph 2, Deep Space Communications
and Navigation Series, Jet Propulsion Laboratory, Pasadena, California,
2000.
[5] C. M. Will and K. Nordtvedt, "Conservation Laws and Preferred Frames in
Relativistic Gravity: I. Preferred-Frame Theories and an Extended PPN
Formalism," Astrophysical Journal, vol. 177, pp. 757?774, 1972.
[6] C. M. Will, Theory and Experiment in Gravitational Physics, Cambridge
University Press, 1981.
There's also a footnote
5 F. B. Estabrook, "Derivation of Relativistic Lagrangian for n-body
Equations Containing Relativity Parameters $\beta$ and $\gamma$,"
JPL Interoffice Memorandum (internal document), Jet Propulsion
Laboratory, Pasadena, California, 1971.
So yes, DE421 does indeed include general relativistic effects.
I believe this is standard in all modern lunar/planetary ephemerises.
A nice discussion of how general relativistic (and indeed, more general
relativistic-gravity) effects are (were) included in celestial mechanics
calculations as of the mid-1980s can be found in
@incollection
{
Hellings-in-GR10,
author = "Ronald W Hellings",
title = "Testing Relativity with Solar System Dynamics",
pages = "365--385",
editor = "B Bertotti and F. de Felice and A. Pascolini",
booktitle = "General Relativity and Gravitation",
booksubtitle = "Invited Papers and Discussion Reports of the
10th International Conference on General Relativity
and Gravitation, Padua (Italy), 3-8 July 1983",
publisher = "Reidel",
address = "Dordrecht (Holland)",
year = 1984,
isbn = "90-277-1819-9",
snote = "++good review of experimental tests of GR
using spacecraft tracking, planetary radar, etc",
}
--
-- "Jonathan Thornburg [remove -animal to reply]" <jth...@astro.indiana-zebra.edu>
Dept of Astronomy & IUCSS, Indiana University, Bloomington, Indiana, USA
"Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral."
-- quote by Freire / poster by Oxfam
Chalky
Mar 12, 2012, 7:50:56 AM3/12/12
to
On Mar 12, 1:16 am, eric gisse <jowr.pi.ons...@gmail.com> wrote:
Of the spacecraft mentioned, only the Pioneers are not gravitationally
bound in the sense that they are designed and programed to leave the
solar system with sufficient speed that they will NEVER come back..
[[Mod. note -- In addition to Pioneer 10 and 11, Voyager 1 and Voyager 2
are (also) not gravitationally bound to the solar system.
-- jt]]
If the classical GR distinction between bound and unbound systems is
valid, NASA should, therefore, have included a cosmological redshift
adjustment factor in the software.
Many people have noticed a correspondence between the published
anomalous acceleration and the Hubble flow, of the form g =~ cHo
However, the problem with this explanation is that the observed
anomalous acceleration is the wrong way round!
The only rational explanation in this context is that NASA HAVE
included a cosmological redshift adjustment, so the anomaly shows up
in reverse, if classical cosmology is wrong.
> Relativistic corrections include time dilation, doppler shift, etc which
> does not include non-relativistic stuff like dust, thermal emissions,
> etc.
>
> www.google.com"planetary epheremis relativistic" 678,000 hits
>
> First result: "Relativistic aspects of the JPL planetary ephemeris"
>
> journals.cambridge.org/article_S1743921309990329
>
> [[Mod. note -- It's open-access, too! -- jt]]
>
Nice one
> Chalky <chalkys...@bleachboys.co.uk> wrote innews:62b2b273-4e7a-4474...@j5g2000yqm.googlegroups.com:
>
> [...]
>
> > This leads me to wonder what GR corrections, precisely, they did use.
>
> Reading the paper and references discussing planetary epheremis
> calculations would be instructive, I would imagine.
>
>
>
> > Did they, for example, conclude Pioneers were not, ultimately,
> > gravitationally bound, by design, thus making cosmological redshift
> > adjustments potentially prudent.
>
> Cosmology has nothing to do with this.
I would not be so sure of this, if I were you
>
> [...]
>
> > This leads me to wonder what GR corrections, precisely, they did use.
>
> Reading the paper and references discussing planetary epheremis
> calculations would be instructive, I would imagine.
>
>
>
> > Did they, for example, conclude Pioneers were not, ultimately,
> > gravitationally bound, by design, thus making cosmological redshift
> > adjustments potentially prudent.
>
> Cosmology has nothing to do with this.
Of the spacecraft mentioned, only the Pioneers are not gravitationally
bound in the sense that they are designed and programed to leave the
solar system with sufficient speed that they will NEVER come back..
[[Mod. note -- In addition to Pioneer 10 and 11, Voyager 1 and Voyager 2
are (also) not gravitationally bound to the solar system.
-- jt]]
If the classical GR distinction between bound and unbound systems is
valid, NASA should, therefore, have included a cosmological redshift
adjustment factor in the software.
Many people have noticed a correspondence between the published
anomalous acceleration and the Hubble flow, of the form g =~ cHo
However, the problem with this explanation is that the observed
anomalous acceleration is the wrong way round!
The only rational explanation in this context is that NASA HAVE
included a cosmological redshift adjustment, so the anomaly shows up
in reverse, if classical cosmology is wrong.
> Relativistic corrections include time dilation, doppler shift, etc which
> does not include non-relativistic stuff like dust, thermal emissions,
> etc.
>
> www.google.com"planetary epheremis relativistic" 678,000 hits
>
> First result: "Relativistic aspects of the JPL planetary ephemeris"
>
> journals.cambridge.org/article_S1743921309990329
>
> [[Mod. note -- It's open-access, too! -- jt]]
>
Hendrik van Hees
Mar 12, 2012, 7:57:37 AM3/12/12
to
On 12/03/12 09:30, Jonathan Thornburg [remove -animal to reply] wrote:
> Chalky<chalk...@bleachboys.co.uk> wrote:
>> the only examples of GR being used for outer solar system
>> computations (that I have come across), are found in the papers on the
>> Pioneer anomalies.
>>
>> Here, Anderson et al. specifically state that GR corrections have
>> additionally been used.
>>
>> Having said that, this is precisely where anomalies have been
>> observed.
>>
>> This leads me to wonder what GR corrections, precisely, they did use.
>
> According to page 3 of
>
> Folkner, Williams, and Boggs,
> "The Planetary and Lunar Ephemeris DE 421"
> IPN Progress Report 42-178 ? August 15, 2009
> http://tmo.jpl.nasa.gov/progress_report/42-178/178C.pdf
>
> "For DE 421, the positions of the Moon and planets were integrated using
> an n-body parameterized post-Newtonian (PPN) metric [5,6,4]."
[[Mod. note -- 44 excessively-quoted lines snipped here. -- jt]]
> Chalky<chalk...@bleachboys.co.uk> wrote:
>> the only examples of GR being used for outer solar system
>> computations (that I have come across), are found in the papers on the
>> Pioneer anomalies.
>>
>> Here, Anderson et al. specifically state that GR corrections have
>> additionally been used.
>>
>> Having said that, this is precisely where anomalies have been
>> observed.
>>
>> This leads me to wonder what GR corrections, precisely, they did use.
>
> According to page 3 of
>
> Folkner, Williams, and Boggs,
> "The Planetary and Lunar Ephemeris DE 421"
> IPN Progress Report 42-178 ? August 15, 2009
> http://tmo.jpl.nasa.gov/progress_report/42-178/178C.pdf
>
> "For DE 421, the positions of the Moon and planets were integrated using
> an n-body parameterized post-Newtonian (PPN) metric [5,6,4]."
The Pioneer Anomaly has been solved by taking into account the
anisotropyic heat radiation/dissipation from it's surface:
Benny Rievers et al 2009 New J. Phys. 11 113032
http://dx.doi.org/10.1088/1367-2630/11/11/113032
[[Mod. note -- See also Turyshev, Toth, Ellis, and Markwardt,
"Support for Temporally Varying Behavior of the Pioneer Anomaly
from the Extended Pioneer 10 and 11 Doppler Data Sets",
Phys Rev Lett 107, 081103 (2011)
http://link.aps.org/doi/10.1103/PhysRevLett.107.081103
commentary http://physics.aps.org/story/print/v28/st8
open-access preprint http://arxiv.org/abs/1107.2886
-- jt]]
--
Hendrik van Hees
Frankfurt Institute of Advanced Studies
D-60438 Frankfurt am Main
http://fias.uni-frankfurt.de/~hees/
Chalky
Mar 12, 2012, 8:24:07 AM3/12/12
to
===========================================================
Moderator's note
================
The pdf seems to be ok. I've no problem viewing it with okular.
HvH.
====================================================================
On Mar 12, 8:30am, "Jonathan Thornburg [remove -animal to reply]"
<jth...@astro.indiana-zebra.edu> wrote:
redirection notice then, before I have time to read much more than the
title, the download aborts because Adobe Acrobat finds irresolvable
errors in the file.
Eric gisse's recommended pdf still downloads fine though.
> "For DE 421, the positions of the Moon and planets were integrated using
> an n-body parameterized post-Newtonian (PPN) metric [5,6,4]."
>
> The table later on that page includes both the inner *and the outer plane=
ce
> Network Data Types for Navigation, Monograph 2, Deep Space Commun=
ications
> and Navigation Series, Jet Propulsion Laboratory, Pasadena, Calif=
ornia,
> 2000.
> [5] C. M. Will and K. Nordtvedt, "Conservation Laws and Preferred Frames =
in
> Relativistic Gravity: I. Preferred-Frame Theories and an Extended=
> title =3D "Testing Relativity with Solar System Dynamics"=
,
> pages =3D "365--385",
> editor =3D "B Bertotti and F. de Felice and A. Pascolini"=
,
> booktitle =3D "General Relativity and Gravitation",
> booksubtitle =3D "Invited Papers and Discussion Reports o=
f the
> 10th International Confer=
ence on General Relativity
> and Gravitation, Padua (I=
> address =3D "Dordrecht (Holland)",
> year =3D 1984,
> isbn =3D "90-277-1819-9",
> snote =3D "++good review of experimental tests of GR
> using spacecraft tracking, planetary r=
adar, etc",
> }
>
> --
> -- "Jonathan Thornburg [remove -animal to reply]" <jth...@astro.indiana-z=
ebra.edu>
> Dept of Astronomy & IUCSS, Indiana University, Bloomington, Indian=
to compute the orbits. Instead they seem to use PPN formalism for the
lowest order corrections to Newtonian gravity.
Moderator's note
================
The pdf seems to be ok. I've no problem viewing it with okular.
HvH.
====================================================================
On Mar 12, 8:30am, "Jonathan Thornburg [remove -animal to reply]"
<jth...@astro.indiana-zebra.edu> wrote:
> Chalky <chalkys...@bleachboys.co.uk> wrote:
> > the only examples of GR being used for outer solar system
> > computations (that I have come across), are found in the papers on the
> > Pioneer anomalies.
>
> > Here, Anderson et al. specifically state that GR corrections have
> > additionally been used.
>
> > Having said that, this is precisely where anomalies have been
> > observed.
>
> > This leads me to wonder what GR corrections, precisely, they did use.
>
> According to page 3 of
>
> Folkner, Williams, and Boggs,
> "The Planetary and Lunar Ephemeris DE 421"
> IPN Progress Report 42-178 ? August 15, 2009
> http://tmo.jpl.nasa.gov/progress_report/42-178/178C.pdf
Unfortunately, when I try to download this, I get a flash of a
> > the only examples of GR being used for outer solar system
> > computations (that I have come across), are found in the papers on the
> > Pioneer anomalies.
>
> > Here, Anderson et al. specifically state that GR corrections have
> > additionally been used.
>
> > Having said that, this is precisely where anomalies have been
> > observed.
>
> > This leads me to wonder what GR corrections, precisely, they did use.
>
> According to page 3 of
>
> Folkner, Williams, and Boggs,
> "The Planetary and Lunar Ephemeris DE 421"
> IPN Progress Report 42-178 ? August 15, 2009
> http://tmo.jpl.nasa.gov/progress_report/42-178/178C.pdf
redirection notice then, before I have time to read much more than the
title, the download aborts because Adobe Acrobat finds irresolvable
errors in the file.
Eric gisse's recommended pdf still downloads fine though.
> "For DE 421, the positions of the Moon and planets were integrated using
> an n-body parameterized post-Newtonian (PPN) metric [5,6,4]."
>
ts*.
> The cited references are
> [4] T. D. Moyer, Formulation for Observed and Computed Values of Deep Spa=
> The cited references are
ce
> Network Data Types for Navigation, Monograph 2, Deep Space Commun=
ications
> and Navigation Series, Jet Propulsion Laboratory, Pasadena, Calif=
ornia,
> 2000.
> [5] C. M. Will and K. Nordtvedt, "Conservation Laws and Preferred Frames =
in
> Relativistic Gravity: I. Preferred-Frame Theories and an Extended=
PPN
> Formalism," Astrophysical Journal, vol. 177, pp. 757?774, 1972.
> [6] C. M. Will, Theory and Experiment in Gravitational Physics, Cambridge
> University Press, 1981.
>
> There's also a footnote
> 5 F. B. Estabrook, "Derivation of Relativistic Lagrangian for n-body
> Equations Containing Relativity Parameters $\beta$ and $\gamma$,"
> JPL Interoffice Memorandum (internal document), Jet Propulsion
> Laboratory, Pasadena, California, 1971.
>
> So yes, DE421 does indeed include general relativistic effects.
> I believe this is standard in all modern lunar/planetary ephemerises.
>
> A nice discussion of how general relativistic (and indeed, more general
> relativistic-gravity) effects are (were) included in celestial mechanics
> calculations as of the mid-1980s can be found in
> @incollection
> {
> Hellings-in-GR10,
> author =3D "Ronald W Hellings",
> Formalism," Astrophysical Journal, vol. 177, pp. 757?774, 1972.
> [6] C. M. Will, Theory and Experiment in Gravitational Physics, Cambridge
> University Press, 1981.
>
> There's also a footnote
> 5 F. B. Estabrook, "Derivation of Relativistic Lagrangian for n-body
> Equations Containing Relativity Parameters $\beta$ and $\gamma$,"
> JPL Interoffice Memorandum (internal document), Jet Propulsion
> Laboratory, Pasadena, California, 1971.
>
> So yes, DE421 does indeed include general relativistic effects.
> I believe this is standard in all modern lunar/planetary ephemerises.
>
> A nice discussion of how general relativistic (and indeed, more general
> relativistic-gravity) effects are (were) included in celestial mechanics
> calculations as of the mid-1980s can be found in
> @incollection
> {
> Hellings-in-GR10,
> title =3D "Testing Relativity with Solar System Dynamics"=
,
> pages =3D "365--385",
> editor =3D "B Bertotti and F. de Felice and A. Pascolini"=
,
> booktitle =3D "General Relativity and Gravitation",
> booksubtitle =3D "Invited Papers and Discussion Reports o=
f the
> 10th International Confer=
ence on General Relativity
> and Gravitation, Padua (I=
taly), 3-8 July 1983",
> publisher =3D "Reidel",
> address =3D "Dordrecht (Holland)",
> year =3D 1984,
> isbn =3D "90-277-1819-9",
> snote =3D "++good review of experimental tests of GR
> using spacecraft tracking, planetary r=
adar, etc",
> }
>
> --
> -- "Jonathan Thornburg [remove -animal to reply]" <jth...@astro.indiana-z=
ebra.edu>
> Dept of Astronomy & IUCSS, Indiana University, Bloomington, Indian=
a, USA
> "Washing one's hands of the conflict between the powerful and the
> powerless means to side with the powerful, not to be neutral."
> =
> "Washing one's hands of the conflict between the powerful and the
> powerless means to side with the powerful, not to be neutral."
-- quote by Freire / poster by Oxfam
Point taken. However, even here they don't appear to use full blown GR
to compute the orbits. Instead they seem to use PPN formalism for the
lowest order corrections to Newtonian gravity.
Chalky
Mar 12, 2012, 9:01:18 AM3/12/12
to
On Mar 12, 11:50=A0am, Chalky <chalkys...@bleachboys.co.uk> wrote:
> On Mar 12, 1:16 am, eric gisse <jowr.pi.ons...@gmail.com> wrote:
>
>
>
>
>
>
>
>
>
> > Chalky <chalkys...@bleachboys.co.uk> wrote innews:62b2b273-4e7a-4474-ac=
> On Mar 12, 1:16 am, eric gisse <jowr.pi.ons...@gmail.com> wrote:
>
>
>
>
>
>
>
>
>
20-7acf...@j5g2000yqm.googlegroups.com:
>
> > [...]
>
> > > This leads me to wonder what GR corrections, precisely, they did use.
>
> > Reading the paper and references discussing planetary epheremis
> > calculations would be instructive, I would imagine.
>
> > > Did they, for example, conclude Pioneers were not, ultimately,
> > > gravitationally bound, by design, thus making cosmological redshift
> > > adjustments potentially prudent.
>
> > Cosmology has nothing to do with this.
>
> I would not be so sure of this, if I were you
>
> Of the spacecraft mentioned, only the Pioneers are not gravitationally
> bound in the sense that they are designed and programed to leave the
> solar system with sufficient speed that they will NEVER come back..
>
> [[Mod. note -- In addition to Pioneer 10 and 11, Voyager 1 and Voyager 2
> are (also) not gravitationally bound to the solar system.
> -- jt]]
Noted.
> > [...]
>
> > > This leads me to wonder what GR corrections, precisely, they did use.
>
> > Reading the paper and references discussing planetary epheremis
> > calculations would be instructive, I would imagine.
>
> > > Did they, for example, conclude Pioneers were not, ultimately,
> > > gravitationally bound, by design, thus making cosmological redshift
> > > adjustments potentially prudent.
>
> > Cosmology has nothing to do with this.
>
> I would not be so sure of this, if I were you
>
> Of the spacecraft mentioned, only the Pioneers are not gravitationally
> bound in the sense that they are designed and programed to leave the
> solar system with sufficient speed that they will NEVER come back..
>
> [[Mod. note -- In addition to Pioneer 10 and 11, Voyager 1 and Voyager 2
> are (also) not gravitationally bound to the solar system.
> -- jt]]
However, these are not even mentioned in the "Relativistic aspects of
the JPL planetary
ephemeris".
Anyway, IIRC, the Pioneers were much better suited for tests of such a
nature.
Whilst we are on this subject, does anyone have a record of the arXiv
addresses for the various Anderson et al. publications on this
subject. Last time I tried a search at arXiv by author, this turned up
nothing relevant.
>
> If the classical GR distinction between bound and unbound systems is
> valid, NASA should, therefore, have included a cosmological redshift
> adjustment factor in the software.
>
> Many people have noticed a correspondence between the published
>
> However, the problem with this explanation is that the observed
> anomalous acceleration is the wrong way round!
>
> The only rational explanation in this context is that NASA HAVE
> included a cosmological redshift adjustment, so the anomaly shows up
> in reverse, if classical cosmology is wrong.
>
> > Relativistic corrections include time dilation, doppler shift, etc whic=
> However, the problem with this explanation is that the observed
> anomalous acceleration is the wrong way round!
>
> The only rational explanation in this context is that NASA HAVE
> included a cosmological redshift adjustment, so the anomaly shows up
> in reverse, if classical cosmology is wrong.
>
h
> > does not include non-relativistic stuff like dust, thermal emissions,
> > etc.
>
> >www.google.com"planetary epheremis relativistic" 678,000 hits
>
> > First result: "Relativistic aspects of the JPL planetary ephemeris"
>
> > journals.cambridge.org/article_S1743921309990329
>
> > [[Mod. note -- It's open-access, too! =A0-- jt]]
> > does not include non-relativistic stuff like dust, thermal emissions,
> > etc.
>
> >www.google.com"planetary epheremis relativistic" 678,000 hits
>
> > First result: "Relativistic aspects of the JPL planetary ephemeris"
>
> > journals.cambridge.org/article_S1743921309990329
>
>
> Nice one
Chalky
Mar 15, 2012, 4:07:36 AM3/15/12
to
> [[Mod. note -- In addition to Pioneer 10 and 11, Voyager 1 and Voyager 2
> are (also) not gravitationally bound to the solar system.
> -- jt]]
In this respect, also note 2nd para of
> are (also) not gravitationally bound to the solar system.
> -- jt]]
http://www.nasa.gov/home/hqnews/2011/dec/HQ_11-402_AGU_Voyager.html
Chalky
Mar 15, 2012, 4:07:37 AM3/15/12
to
On Mar 12, 11:57=A0am, Hendrik van Hees <h...@fias.uni-frankfurt.de>
wrote:
> [[Mod. note -- See also Turyshev, Toth, Ellis, and Markwardt,
> "Support for Temporally Varying Behavior of the Pioneer Anomaly
> =A0from the Extended Pioneer 10 and 11 Doppler Data Sets",
> Phys Rev Lett 107, 081103 (2011)http://link.aps.org/doi/10.1103/PhysRevLe=
tt.107.081103
> commentary =A0 =A0http://physics.aps.org/story/print/v28/st8
> open-access preprint =A0http://arxiv.org/abs/1107.2886
> -- jt]]
Yes, the last Anderson et al. paper that I read on this subject, did
indicate that the observed anomaly was decreasing, but NOT that it was
decreasing exponentially to zero.
Figure 1 of this paper (stochastic view) confirms that this decrease
has stopped, and even indicates a slight rise for both Pioneers, in
the last set of observations considered for each.
In any case, I can't understand their suggestion the observed anomaly
is caused by an anomalous ever increasing spin of both spacecraft.
Isn't this a bit like jumping out of the frying pan into the fire?
If anything, the spins of these spacecraft should be slowing down.
wrote:
> [[Mod. note -- See also Turyshev, Toth, Ellis, and Markwardt,
> "Support for Temporally Varying Behavior of the Pioneer Anomaly
> Phys Rev Lett 107, 081103 (2011)http://link.aps.org/doi/10.1103/PhysRevLe=
tt.107.081103
> commentary =A0 =A0http://physics.aps.org/story/print/v28/st8
> open-access preprint =A0http://arxiv.org/abs/1107.2886
> -- jt]]
Yes, the last Anderson et al. paper that I read on this subject, did
indicate that the observed anomaly was decreasing, but NOT that it was
decreasing exponentially to zero.
Figure 1 of this paper (stochastic view) confirms that this decrease
has stopped, and even indicates a slight rise for both Pioneers, in
the last set of observations considered for each.
In any case, I can't understand their suggestion the observed anomaly
is caused by an anomalous ever increasing spin of both spacecraft.
Isn't this a bit like jumping out of the frying pan into the fire?
If anything, the spins of these spacecraft should be slowing down.
Chalky
Mar 15, 2012, 4:07:37 AM3/15/12
to
> The Pioneer Anomaly has been solved by taking into account the
> anisotropyic heat radiation/dissipation from it's surface:
>
> Benny Rievers et al 2009 New J. Phys. 11 113032http://dx.doi.org/10.1088/=
> anisotropyic heat radiation/dissipation from it's surface:
>
1367-2630/11/11/113032
If what you say is true, how come they did not present a single figure
showing an unambiguous prediction, or even a figure showing
correlation between best fit predictive model, and observation?
They did, however, present 15 figures, each comprising multiple
images, that did not do either.
In any case, IIRC, the first Anderson et al. paper says they DID
consider thermal radiation considerations, but these could not explain
the anomaly.
> [[Mod. note -- See also Turyshev, Toth, Ellis, and Markwardt,
> "Support for Temporally Varying Behavior of the Pioneer Anomaly
Chalky
Mar 20, 2012, 9:51:07 AM3/20/12
to
At
http://www.nasa.gov/mission_pages/voyager/voyager20110609.html and
http://www.nasa.gov/mission_pages/voyager/index.html (latest news),
NASA currently still show a heliosphere that is far from spherical, in
relation to the Voyager and the Earth.
Why is that?
After some pondering it seems to me the most likely explanation is
that NASA (and/or artist) have crudely employed a highly lopsided
Gaussian grid, to display Voyager and Earth of commensurate size
(despite the fact there are far better ways of doing this).
If so, I think NASA should declare this, to allow more people to see
the reality of the situation, more easily and quickly.
http://www.nasa.gov/mission_pages/voyager/voyager20110609.html and
http://www.nasa.gov/mission_pages/voyager/index.html (latest news),
NASA currently still show a heliosphere that is far from spherical, in
relation to the Voyager and the Earth.
Why is that?
After some pondering it seems to me the most likely explanation is
that NASA (and/or artist) have crudely employed a highly lopsided
Gaussian grid, to display Voyager and Earth of commensurate size
(despite the fact there are far better ways of doing this).
If so, I think NASA should declare this, to allow more people to see
the reality of the situation, more easily and quickly.
Chalky
Mar 22, 2012, 2:29:37 PM3/22/12
to
On Mar 20, 1:51 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:
> At
http://www.nasa.gov/mission_pages/voyager/voyager20110609.html and
http://www.nasa.gov/mission_pages/voyager/index.html (latest news),
> NASA currently still show a heliosphere that is far from spherical, in
> relation to the Voyager and the Earth.
>
> Why is that?
N.B. For answer, see
> At
http://www.nasa.gov/mission_pages/voyager/voyager20110609.html and
http://www.nasa.gov/mission_pages/voyager/index.html (latest news),
> NASA currently still show a heliosphere that is far from spherical, in
> relation to the Voyager and the Earth.
>
> Why is that?
http://en.wikipedia.org/wiki/Heliosphere#Cassini_results and
immediately following Interstellar Boundary Explorer results.
"It means the textbook picture of the heliosphere [snip] is wrong."
There is also now a VAST improvement in ART for Voyager, at
http://photojournal.jpl.nasa.gov/catalog/PIA12310
All 3 references together, confirm that the previously referenced NASA
data for Voyagers, is therefore wrong too.
The JPL ref needs quicktime installed to see the video.
This is a free download from Apple, but, _be warned_, you should read
the latest comments at http://store.apple.com/us/reviews/D3381Z/A ,
before being levered into parting with any cash, for Apple's
temptingly priced Pro version.
Chalky
Mar 22, 2012, 5:43:07 PM3/22/12
to
On Mar 20, 1:51 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:
> At
http://www.nasa.gov/mission_pages/voyager/voyager20110609.html and
http://www.nasa.gov/mission_pages/voyager/index.html (latest news),
> NASA currently still show a heliosphere that is far from spherical, in
> relation to the Voyager and the Earth.
>
> Why is that?
N.B. See, especially,
http://www.nasa.gov/mission_pages/voyager/voyager20110609.html and
http://www.nasa.gov/mission_pages/voyager/index.html (latest news),
> NASA currently still show a heliosphere that is far from spherical, in
> relation to the Voyager and the Earth.
>
> Why is that?
http://en.wikipedia.org/wiki/Heliosphere#Cassini_results
This confirms my previously referenced, and NASA displayed Voyagers
data, is wrong, or at least, seriously out of date.
Richard D. Saam
Apr 12, 2012, 2:24:05 AM4/12/12
to
On 3/15/12 3:07 AM, Chalky wrote:
> On Mar 12, 11:57am, Hendrik van Hees<h...@fias.uni-frankfurt.de>
explain Pioneer deceleration but in order to do so, empirical surface
emissivity factors must be used in the radiative force model. In the
end, it becomes curve fitting with selected emissivity factors. We
cannot even model how radiation forces make the Crookes radiometer go in
a controlled laboratory condition here on earth.
There is Pioneer data that can be used help resolve this Pioneer
deceleration issue and that is direct comparison of undisturbed spin
deceleration through Pioneer moment of inertial to translational
deceleration of Pioneer mass.
I have made this recommendation at least 10 times to relevant
investigators over the years with no response.
Richard D. Saam
> On Mar 12, 11:57am, Hendrik van Hees<h...@fias.uni-frankfurt.de>
> wrote:
>
>> The Pioneer Anomaly has been solved by taking into account the
>> anisotropyic heat radiation/dissipation from it's surface:
>>
>> Benny Rievers et al 2009 New J. Phys. 11 113032http://dx.doi.org/10.1088/=
> 1367-2630/11/11/113032
>
> If what you say is true, how come they did not present a single figure
> showing an unambiguous prediction, or even a figure showing
> correlation between best fit predictive model, and observation?
>
> They did, however, present 15 figures, each comprising multiple
> images, that did not do either.
>
> In any case, IIRC, the first Anderson et al. paper says they DID
> consider thermal radiation considerations, but these could not explain
> the anomaly.
>
>> [[Mod. note -- See also Turyshev, Toth, Ellis, and Markwardt,
>> "Support for Temporally Varying Behavior of the Pioneer Anomaly
>
>> The Pioneer Anomaly has been solved by taking into account the
>> anisotropyic heat radiation/dissipation from it's surface:
>>
>> Benny Rievers et al 2009 New J. Phys. 11 113032http://dx.doi.org/10.1088/=
> 1367-2630/11/11/113032
>
> If what you say is true, how come they did not present a single figure
> showing an unambiguous prediction, or even a figure showing
> correlation between best fit predictive model, and observation?
>
> They did, however, present 15 figures, each comprising multiple
> images, that did not do either.
>
> In any case, IIRC, the first Anderson et al. paper says they DID
> consider thermal radiation considerations, but these could not explain
> the anomaly.
>
>> [[Mod. note -- See also Turyshev, Toth, Ellis, and Markwardt,
>> "Support for Temporally Varying Behavior of the Pioneer Anomaly
>> from the Extended Pioneer 10 and 11 Doppler Data Sets",
>> Phys Rev Lett 107, 081103 (2011)http://link.aps.org/doi/10.1103/PhysRevLe=
> tt.107.081103
>> Phys Rev Lett 107, 081103 (2011)http://link.aps.org/doi/10.1103/PhysRevLe=
> tt.107.081103
>> commentary http://physics.aps.org/story/print/v28/st8
>> open-access preprint http://arxiv.org/abs/1107.2886
>> -- jt]]
There is no doubt that anisotropic heat radiation/dissipation can
>> open-access preprint http://arxiv.org/abs/1107.2886
>> -- jt]]
explain Pioneer deceleration but in order to do so, empirical surface
emissivity factors must be used in the radiative force model. In the
end, it becomes curve fitting with selected emissivity factors. We
cannot even model how radiation forces make the Crookes radiometer go in
a controlled laboratory condition here on earth.
There is Pioneer data that can be used help resolve this Pioneer
deceleration issue and that is direct comparison of undisturbed spin
deceleration through Pioneer moment of inertial to translational
deceleration of Pioneer mass.
I have made this recommendation at least 10 times to relevant
investigators over the years with no response.
Richard D. Saam
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