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maurol2
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This thread has been split off from the [thread=104694]Gravity Probe B[/thread] thread. Some posts here are duplicated in the above thread to keep a sense of continuity -- cristo
Yes, but aren't you being dogmatic? Polestar101 is suggesting that the solar system is not orbiting the galaxy (at least, not only) but a binary companion(or something else, I would say). In that case the change in angular velocities(and in so called geodetic precession) will be greater than the one caused by the orbit around the galaxy.
There's some evidence for this. See the "http://en.wikipedia.org/wiki/Solar_apex" " entry on Wikipedia.
I've also found out a paper from circa 1880,
"On the Movement of the Solar System in Space, deduced from the Proper Motions of 1167 Stars"
Here's a link to http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1863MNRAS..23..166D&link_type=GIF" where you can find the abstract.
That paper is clearly pointing to a movement that is NOT the movement around the galaxy, but a movement with a far greater amount of change.
Please note also that the literature tends to differentiate between the movement of the Local Standard of Rest (LSR), which is the assumed movement around the galaxy, of the solar system and its local surroundings, and the proper movement of the solar system towards the solar apex.
I don't understand why these movements of the Solar system towards the so called solar apex, which are being studied since at least the nineteen century, are unknown or are not taken into account. Why these issues were forgotten or ignored in the course of time? Maybe because there's no known mechanism to explain them?
Regards,
Mauro
Garth said:The "solar system’s change in angular velocity relative to the guide star" will be caused by its motion around the galaxy, I have dealt with the motion of the galaxy itself above (it is negligible).
Orbiting the galaxy would cause a geodetic precession of
[tex](\frac{M_G}{M_E})^\frac{3}{2}(\frac{R_E}{R_G})^\frac{5}{2} \times 8 \text{arcsecs/yr }[/tex]
(See MTW 'Gravitation' page 1119 eq 40.35)
i.e. about 10-8 arcsecs per year.
I think this can also be safely ignored!
Garth
Yes, but aren't you being dogmatic? Polestar101 is suggesting that the solar system is not orbiting the galaxy (at least, not only) but a binary companion(or something else, I would say). In that case the change in angular velocities(and in so called geodetic precession) will be greater than the one caused by the orbit around the galaxy.
There's some evidence for this. See the "http://en.wikipedia.org/wiki/Solar_apex" " entry on Wikipedia.
I've also found out a paper from circa 1880,
"On the Movement of the Solar System in Space, deduced from the Proper Motions of 1167 Stars"
Here's a link to http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1863MNRAS..23..166D&link_type=GIF" where you can find the abstract.
That paper is clearly pointing to a movement that is NOT the movement around the galaxy, but a movement with a far greater amount of change.
Please note also that the literature tends to differentiate between the movement of the Local Standard of Rest (LSR), which is the assumed movement around the galaxy, of the solar system and its local surroundings, and the proper movement of the solar system towards the solar apex.
I don't understand why these movements of the Solar system towards the so called solar apex, which are being studied since at least the nineteen century, are unknown or are not taken into account. Why these issues were forgotten or ignored in the course of time? Maybe because there's no known mechanism to explain them?
Regards,
Mauro
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