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16

Possibly you are labouring under the misapprehension that the number of photons is somehow a conserved quantity? That isn't true, there are more photons at any given wavelength when you are deeper into the star, because there is a temperature gradient. Cooler material further out is less emissive because fewer atoms are in excited states. The temperature ...


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It is the other way around. An isolated, point-like charged particle like an electron cannot absorb a photon. It is forbidden, because energy and momentum cannot be simultaneously conserved. Only scattering is permitted in such circumstances. However, a charged particle that is within the electric field of another (e.g. an electron in the electric field of a ...


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That's a timelaps video, most likely created from a sequence of photos. It's easy to choose sensitivity and ISO settings on normal cameras such that the night sky at the darkest night is over-exposed. The moon light looks like sunlight - as it simply is reflected sunlight. E.g. see https://cloud.planetmaker.de/index.php/s/yJ7AXWG4dEC6csW - it's a an exposure ...


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tl;dr: You are seeing Astronomical twilight growing brighter through the month of August 2017 at the south pole! For more on the Moon's motion see the excellent answer to How does the Moon move in the "night" sky as seen from the poles? Here are two screenshots and a calculation of the altitude and azimuth of the Moon and the Sun throughout the ...


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