The Sun is not a sphere. Neither is the Earth.Originally posted by photon
It seems they would be circular because with a spherical object such as the sun, and a spherical orbiting object such as a planet, that the orbit should be a circle. In all the pictures in books, it shows a grid, sucked down by a shere. The "pit" in the space-time grid is always shown as a circle.
The gravitational field of a spherically symmetric body is spherically symmetric, but this does not imply that orbits around that body must also be spherically symmetric. (It's like claiming that if a gravitational field points straight down, all bodies should fall straight: they don't have to, they can move in parabolas.)Originally posted by photon
It seems [orbits] would be circular because with a spherical object such as the sun, and a spherical orbiting object such as a planet, that the orbit should be a circle.
Hi photon and welcome to this string,Originally posted by photon
ah. Thanks guys, I think I get it now.
Seems to me that a math scholar and a fairly able logician should know that this isn't correct anyway.Originally posted by NEOclassic
but the notion that the Sun is at a single elliptic focus is ridiculous
Scattered around.Originally posted by jimbot
Are the apogees of the planets aligned along a common axis (+-10 degrees)? Or are they scattered around?
Here's a table which can answer your question:Originally posted by jimbot
Are the apogees of the planets aligned along a common axis (+-10 degrees)? Or are they scattered around?
Hi Nereid,Originally posted by Nereid
If you've got some time (and a few software aids, even XL), you can use the data in the link of my last post to do your own calculations as to where the Sun is, in relation to (any of) the planets, and any elliptical approximations to their orbits. Perhaps you could also share with us a) how you did the calculations, and b) what you found?
This is just not true. The Newtonian two-body solution is perfectly self-consistent and agrees up to a good degree with experiment and measurement. Corrections for GR effects do not do what you say. Of course the speeds at perihelion are different from the speeds at aphelion; that was one of the observed data that had to be explained, and it is visible here on earth as the fact that "noon by the sun" moves backward through the clock relative to "noon by a uniform clock" during the winter (earth's perihelion is January 2) so that by its max in February it is almost 15 minutes earlier. This is entirely due to the earth moving faster than average as it approaches and scoots by perihelion. You might also try counting the days from Fall Equinox to Spring Equinox and comparing that count to the number of days from Spring Equinox to Fall Equinox.had said that the sun was not at a focus of planetary ellipses on the grounds that although an ellipse was mathematically perfect there was inconsistency relating to the physical modeling (implied by equal area sweeps rule) that implies that the trajectory velocity at perihelion differs from that at aphelion. Remodeling in such a manner so as to adjust the physical reality to agree with the math, requires the postulation of a virtual massless focus at the position (determined by the eccentricity)between that focus and trajectory a aphelion that equals the distance between the sun-center and the perihelion.
Hello Nereid,Originally posted by Nereid
Jim/NEOclassic: you may be making things more complicated than they need to be.
Try this: assume there's only the Earth and the Moon (a 2-body problem) and ignore GR for the moment. Assume a circular orbit. Assume the Earth's mass is very, very much greater than the Moon's, perhaps the Moon is just a 'test mass'. Where's the centre of the circle? Where's the Earth?
Now assume the Earth and Moon have equal masses, and are not in elliptical orbits. How do the two bodies orbit each other? in a circle? where's the centre of the circle? what's at the centre?
Now if the Earth:Moon mass ratio is something between 0 and 1, still assuming circular orbits ... where's the centre of the circle(s)?
Finally, if the circles are just very slightly elliptical, more elliptical, ... ?
It seems that you are confusing two different points here:Originally posted by NEOclassic
Assuming that the Earth's mass be very very much greater than that of the moon's obfuscates the reality that most of the solar orbits' fulcrums are at radii from the sun's center less than the radius of the sphere of incandescence contrasted with the earth-moon fulcrum that is away from the earth's surface as manifest by the Lunar influence on the earth's oceanic tides. An even more nearly perfect explanation of the position of the true fulcrum is shown by the SOHO space telescopic camera that is adjusted toward that virtual point in an effort to overcome optical aberrations that are evident when eclipses are observed from the face of the earth.