# Tagged Questions

Questions on systems to uniquely determine position of a point or other geometric element on a manifold such as Euclidean space.

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### Could celestial coordinates be encoded into three-word combinations?

I came across this cool tool which encodes geographic coordinates into 3 dictionary words - table.lamp.chair - for example. You can see their map here https://map.what3words.com/. It divides the world ...
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### Does the retrograde movement affect the true angular distance between 2 planets?

I need to calculate the relative angular path between two planets in the geocentric view or in other words the number of degrees of a circle one planet travels away from another planet around the ...
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### a random distribution of RA&Dec

How to make random positions in Equatorial coordinate system? If I divide Dec between -90 and 90 evenly, the space distribution is not random.
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### a math problem in Spherical astronomy [closed]

this is an exercise from Spherical astronomy by Smart, which i want to solve: $\frac{d \eta}{d H}= -\cos(\phi) \cos (A) (\sin (z))^{-1}$ when $\phi$ is latitude, $\eta$ is parallax, $H$ is sidereal ...
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### Pointing direction movement of a fixed camera

first doubt here: I have a fixed camera, whose coordinates I know, pointing to the sky. After the first image, I performed a astrometry calculation from nova.astrometry.net and I got, among other ...
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### Calculating azimuth from equatorial coordinates

I try to get the azimuth of an object from its equatorial coordinates using this formula: $a = \arctan2(\sin(θ - α), \sin φ * \cos(θ - α) - \cos φ * \tan δ)$ Where φ = geographic latitude of the ...