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The main point is that it all depends on the optics quality. Nikon is a good brand, but $300 for a 50mm binocular is way too much. Remember the golden rule while buying any kind of telescope or binocular: Aperture matters, not the Magnification. In a binocular, say "7x50" models, you get 7x magnification with 50mm aperture, which restricts how far you can ...


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There is no gravitational phenomenon associated with exact alignment. (moreover, exact alignment never happens, there is always a small deviation). The directions of tidal forces are aligned and hence sum-up for alignment, but this maximum is quite broad and nothing spectacular happens near exact alignment. You need close to exact alignment (depending on ...


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Referring to your #gravity tag this would only create a peak in the planets tidal forces. But this would be a visible effect in case the planets would be big and close enough... Last night happened that with Sun-Earth-Moon although they were not aligned as you say. To sum up: a proper alignment would increase the effect of tidal forces.


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Extending @Aaron: Which also does matter, that it is relatively common in the universe ( https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements ). For example, rubidium has a much lower ionization energy, but it can only be found in traces, while sodium is one of the most frequent elements in the stony planets.


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From http://science.nasa.gov/science-news/science-at-nasa/2000/ast26oct_1/: "When a Leonid meteoroid hits the Moon it vaporizes some dust and rock," explains Jody Wilson of the Boston University Imaging Science Team. "Some of those vapors will contain sodium (a constituent of Moon rocks) which does a good job scattering sunlight. If any of the ...


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Even though I'm a professional astronomer (but not an expert on this field), I don't have a good answer. AFAIK, this question is still open. Actually, the fact that most planets in the Solar system rotate in the same sense as they orbit the Sun is an important constraint on possible planet formation scenarios (of which still several are presently discussed ...


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I can't give you an explicit ant mathematical explanation but maybe this simulations give you a hint. If you look at the bottom one with beta=0.01 (faster initial rotation speed) you will see how possibly a binary or even ternary system is formed. I guess this could be picked as an example for planetary formation. ...


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The reason most of the planets in our solar system (with the exception of Venus and Uranus) rotate in a anti-clockwise direction is due to the proto-planetary disk that formed the Sun and all the planets around it. Since the proto-planetary disk was spinning in a anti-clockwise direction any objects that formed out of the same disk would have shown the same ...


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All matter radiates (except if it's at absolute zero temperature), regardless of its composition (you got that of Mercury badly wrong). The most important form of radiation is the black-body radiation which only depends on the temperature of the material, but line emission and absorption may also be important (but depends on the composition and ionisation ...


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Stars' light is produced by thermonuclear fusion of hydrogen, helium and other elements at their nucleus. This processes are impossible in planets since you need high pressures and temperatures >10,000 k



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