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Is the SOI a spherical region or a oblate-spheroid-shaped region? The sphere of influence is neither a sphere nor an oblate spheroid. It is a surface with no name. An approximation of this surface is $$\left(\frac r R\right)^{10}(1+3\cos^2\theta) = \left( \frac m M \right)^4$$ This is neither a sphere nor an oblate spheroid, and this is but an ...


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As tomassch said, the analogy of gravity and electromagnetism is not valid by current observations. However, some systems, depending on how they are arranged, can have gravitational interactions that may launch other objects at extremely high speeds. This is the case with three-body systems and gravitational assist.


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There are at least two interpretations to this problem: Per Wikipedia, Jupiter's surface gravity is $2.528$ times Earth's. Thus, if the Earth were $2.528$ times denser, it would have the same surface gravity as Jupiter. The Earth's current density is $5.514$ grams per cubic centimeter, so the new density would be $2.528 \times 5.514$, or about $13.9394$ ...


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You only need two formulae. Gravitational field of a spherically symmetric mass distribution is given by $$g = \frac{GM}{R^2},$$ where $M$ is the mass inside a radius $R$. The second formula is the average density of a sphere is its mass divided by its volume, hence $$\rho = \frac{M}{(4/3)\pi R^3}$$ These two formulae can obviously be put together to give ...


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Unless the stars comes so close that they actually collide, two stars will not be able to catch each other gravitationally. The reason is energy conservation: As they approach each other, their potential energy is converted into kinetic energy, increasing their velocities. When they are closest, their velocities are at their highest, but since there's ...


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Stars are far apart from other celestial bodies because of mass, temperature, elements. The way in which a star burns, henceforth its mass, depending on its given place in the cosmos. A small or dwarf star burns hot and dies fast, while a larger star such as our own star (the sun), burns at a more consecutive speed, and burns longer, now to ask a question ...


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Any object with mass (even you) has gravity. The mutual attractive force between two objects is given by the formula $$ F = G \frac{M_1 M_2}{R_{12}^2}, $$ where the two mass are $M_1$ and $M_2$ and $R_{12}$ is the separation of their centres of mass. So to answer your question we need to define some sort of parameter that specifies what you mean by ...


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Feng and Gallo have several articles in refereed journals including "Modeling the Newtonian Dynamics for Rotation Curve Analysis of Thin-Disk Galaxies" in Research in Astronomy and Astrophysics, "Galactic Rotation Described by a Thin-Disk Gravitational Model Without Dark Matter" in the Journal of Cosmology, "Deficient Reasoning for Dark Matter in Galaxies" ...


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As noted by Conrad Turner, the approximate shape of the Earth is an oblate spheroid, though it is so close to spherical that you would be pretty hard-pressed to see the difference without precise scientific equipment. This web page has some pretty good information on this topic that you might be interested in. When we talk about this shape, we are generally ...


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The form of the Earth is a approximately (to a very good approximation) an oblate spheroid (difference between the polar diameter and equatorial diameter is ~20km which is ~1/300 of the mean diameter). The shape is distorted by tides (both in the solid body as well as the sea) and by topography. Topographical variation is about +10 to -10km (height of ...



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