New answers tagged light
2
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 ...
0
As @Codosaur mentioned earlier, it is the electrons that absorb the the energy of the photon and not the Nucleus.
Let's take a theoretical example to see how this works.
Imagine an atom without any disturbances. It's electrons are in a relaxed state. That is, the electrons are stable in their orbits.
Now, a photon's energy is absorbed by the atom. This can ...
0
It's the electrons of an atom that absorb the energy of the photon, not the nucleus. The frequency of the incoming light wave is at or near the energy levels of the electrons in the matter. The electrons will absorb the energy of the light wave and change their energy state.
Atoms are perpetually vibrating at any temperature above zero Kelvin. Some of those ...
0
The atmospheric layer that produces the absorption lines acts somewhat like a mirror at these frequencies and scatters the light back into the sun (although this is diffuse reflection not specular reflection like an actual mirror). In principle, light is scattered also outwards (with a probability of 1/2 for each scattering event), but since the layer is ...
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 ...
-1
The explanation you were previously given is incorrect.
As the sun's atmosphere extends outward, it is reduced in density and temperature, such that light which is absorbed by it is not re-emitted, or is re-emitted later at a cooler temperature (lower frequency) due to the sun's own atmospheric convection and the emission of other forms of solar radiation.
1
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 ...
2
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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