# Tag Info

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Imagine if all the astronauts and cosmonauts inside the ISS started bouncing off the walls, would this impact the trajectory of the ISS. The physics says no. The ISS actually had a problem like this, but it does not result in orbital trajectory change. The center of mass of an object in space will move along its path regardless of motion within or about the ...

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I'd like to add a clarification to the other answers, some of which seem to imply that the precession of Mercury's orbital perehelion is owing to general relativistic frame dragging. In particular, the statement that the Sun drags the fabric of space time around with it could be, in my opinion, misleading because most of the precession is NOT owing to "frame ...

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The solution of Einstein, contesting Newton´s laws, was challenged by several scientists including Dr. Thomas Van Flandern astronomer who worked at the U.S. Naval Observatory in Washington. According to them, Einstein would have gotten this information (43 "arc) and" adjusted "the arguments for the result of the equation, previously known, were achieved, ...

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Both ecliptic and galactic coordinates are spherical coordinate systems that involve measuring angles on the celestial sphere. There are two equivalent ways to convert between such two coordinate systems: A transformation by deriving a general rotation matrix, for example using Euler angles; Finding an appropriate spherical triangle and calculating its ...

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Perhaps you're looking for something you can just punch into a spreadsheet instead of a generic matrix transformation? I've found it's easier to go from equatorial to other systems. So you can move it from ecliptic to equatorial (in degrees): $\alpha=tan^{-1}(\frac{sin(\lambda) *cos(\epsilon)-tan(\beta)*sin(\epsilon)}{cos(\lambda)})$ ...

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Elliptic coordinates are a general coordinate system while galactic coordinates are a set of 2-dimensional spherical coordinates with a heliocentric origin. Thus the conversion between the two would just be the conversion between elliptical and 2-dimensional spherical (i.e. polar) coordinates. This is easy to derive by writing each system in terms of ...

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"Focus" is an inconvenient word if you're thinking of changing the potential, because if you do then the orbits are no longer conics and the word kind of loses its meaning. That aside, let me see if I understood your question correctly: Given a gravitational potential that's spherically symmetric around a central point $\mathbf{r}_0$, and which has a ...

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The velocity of an orbit around some central object can be easily calculated for a circular orbit. Let us assume that there is some central Force $F=c\cdot r^\alpha$, where $c$ and $\alpha$ are some constants (for gravity $c=Gm_1m_2$ and $\alpha=-2$). For a stable orbit, this central force must be equal to the necessary centripetal force (not balance the ...

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The best way to explain it (and even the way Kepler's second law can be derived) is by conservation of angular momentum. The latter is given by $$\mathbf{L}=\mathbf{r}\times m\mathbf{v},$$ where $\mathbf{r}$ is the position vector and $\mathbf{v}$ is velocity. Since this quantity has to be conserved for the motion of the object at all times, assuming an ...

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To a first approximation distance covered by the Moon is the same as the Earth's, but you can also estimate the correction to first order. Assume both orbits are circular and in the same plane since any deviations will affect only smaller order corrections. Represent the position in the orbital plane as a complex number \$Z = R e^{2\pi i (t/Y)} + r ...

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