User:Mark Widmer/sandbox: Difference between revisions

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(→‎Hill sphere of the Sun: Working on potential new section "Hill sphere of the Sun" (in progress))
imported>Mark Widmer
(→‎Hill sphere of the Sun: edits in progress)
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It is reasonable to consider two phenomena that could determine the Sun's Hill radius. One is the effect of the galaxy as a whole, as the Sun orbits the galactic center every xxx years. However, the distribution of the matter in the galaxy is such that the net gravitational force on the Sun is not inversely proportional to the distance from the galaxy's center. An inverse-square dependence is assumed in deriving the above formulas for the Hill radius.
It is reasonable to consider two phenomena that could determine the Sun's Hill radius. One is the effect of the galaxy as a whole, as the Sun orbits the galactic center every xxx years. However, the distribution of the matter in the galaxy is such that the net gravitational force on the Sun is not inversely proportional to the distance from the galaxy's center. An inverse-square dependence is assumed in deriving the above formulas for the Hill radius.


Another possible
Rather than considering the effect of the galaxy as a whole on objects orbiting the Sun, one can consider the effect of individual stars. In particular, that of the nearby Alpha Centauri star system. However, as the Sun and Alpha Centauri are not in bound orbits about each other, the earlier Hill radius formulas do not apply.


Since the Sun does not orbit a compact object. Two considerations that determine the Sun's Hill sphere are (1) that the Sun orbits the center of mass of the extended distribution of objects that makes up the galaxy, and (2) the nearest star, Alpha xxx, can affect the orbits of objects far enough from the Sun, even though the Sun does not orbit Alpha xxx.
In the absence of a simple calculation, one can use the farthest distance to objects known to orbit the Sun to at least get a minimum value for the Hill radius.
 
? Calculation/estimate of Sun's Hill radius due to Alpha Centauri?


==Hill sphere of objects that orbit Earth==
==Hill sphere of objects that orbit Earth==

Revision as of 20:13, 18 August 2021

Sandbox. Mark Widmer (talk) 01:17, 5 August 2021 (UTC)

Draft for additions to Hill_sphere New sections:

Hill sphere of the Sun

The formulas listed earlier are not applicable to calculating a Hill radius for the Sun, even though the Sun must have a Hill sphere owing to the presence of other stars in the galaxy that will significantly perturb the orbit of any object that is far enough away.

It is reasonable to consider two phenomena that could determine the Sun's Hill radius. One is the effect of the galaxy as a whole, as the Sun orbits the galactic center every xxx years. However, the distribution of the matter in the galaxy is such that the net gravitational force on the Sun is not inversely proportional to the distance from the galaxy's center. An inverse-square dependence is assumed in deriving the above formulas for the Hill radius.

Rather than considering the effect of the galaxy as a whole on objects orbiting the Sun, one can consider the effect of individual stars. In particular, that of the nearby Alpha Centauri star system. However, as the Sun and Alpha Centauri are not in bound orbits about each other, the earlier Hill radius formulas do not apply.

In the absence of a simple calculation, one can use the farthest distance to objects known to orbit the Sun to at least get a minimum value for the Hill radius.

Hill sphere of objects that orbit Earth

The Moon -- added to article

Artificial satellites in low-Earth orbit -- added to article

Hill sphere of an object orbiting with another comparable-mass object