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I recommend visiting a few university Astronomy departments, and investigating their PhD programmes. While a PhD may seem like a big thing to undertake as a retired person (and it is), you will certainly be doing real research. Just discussing the possibilities with people in a few Astronomy departments will lead to other ideas, or actual research projects ...


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By viewing the star and the amount of cycles it went through we can determine what access material are available within its solar system. Next we look at the habitat zone of that star and the size of the planet. It the planet is in the habitat zone then there is a chance for liquid water. If it is also roughly the size of Earth or a little larger it can hold ...


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The answer to your question for that specific planet is No. There is no way at this point in time to tell if Kepler-442b is a big barren rock or a water world or like earth for that matter. They only know it is there because it passes in front of the star it is orbiting and that dims the light. That is the only reason they know it is there. This planet ...


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It is possible that the basic colouration of the visible surface would lead you to some conclusions - the presence, or otherwise, of clouds for example. Maybe filtering the light through a diffraction grating would give you some idea of the atmosphere or surface's constituent elements. If you have some serious kit, you could wait and hope that the planet ...


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I think the methodologies you're asking for are still very much being worked out (and you might want to think of this as looking for a model rather than an equation -- the latter is too simplistic). It might be best to find some relevant articles (starting with some that are geared to the layman) and work from there: ...


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I think what you have established here is just that $\rho$ tends to increase with mass. The density of planets isn't constant. Let $\rho = \rho_0 (M/M_{earth})^{\alpha}$, so that $M = (4/3)\pi R^{3} \rho_0 (M/M_{earth})^{\alpha}$ Then $$g = \frac{GM}{R^2} = \frac{4\pi G}{3} R \rho$$ Replace $R$ with $(3M/4\pi \rho)^{1/3}$ so that $$ g = \frac{4\pi G}{3} ...


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Data from observatory archives is a good way to go. Here is another one with tons of imaging datasets: http://archive.eso.org


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For planets of constant mean density you have: $$ M=\rho \times 4\pi r^3 $$ and the surface value of $g$ is: $$ g(r)=\frac{GM}{r^2}=G \times \rho\times 4 \pi \times r $$ So for bodies of constant density the surface gravity is proportional to the radius, and the slope as $r \to 0$ tells you the density. So for bodies of equal density $\log(g(r)) \to -\infty$ ...


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In addition to the capture mechanisms mentioned by Andy, you also need to take into account the stability of any orbit due to perturbations from tidal effects. E.g. in case of our Moon, there are no stable orbits possible. Every satellite put in orbit around the Moon had had to implement course corrections to prevent it from prematurely crashing into the ...


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This is due to the mechanics of capture. For one object (moon) to be captured by a another (planet), some energy has to be removed from the system. If the incoming moon has an existing satellite then it would be ejected, carrying a lot of kinetic energy. If a small body were to be captured by the planet/moon combination, it would usually be captured by ...


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It's pretty easy to create a dataset for yourself using remotely controlled telescopes. I've used iTelescope in the past and had a good experience. Their "starter" account costs $20 and should be good to get you going.


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Try the NASA data catalog, https://data.nasa.gov/data. Also Try the Keck Observatory Archive, KOA, http://nexsci.caltech.edu/archives/koa/index.shtml. Look for raw images. of clusters or galaxies.


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You could use archival data, e.g., from the WISE mission: http://irsa.ipac.caltech.edu/applications/wise/ The data are reduced as well as photometrically and astrometrically calibrated, which should make the image combination a lot easier. Just type in random coordinates and download data for a field with the desired number of frames. You can also try ...



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