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2

The sun rotates in anti-clockwise direction(when viewed from north) But the Sun does not rotate as a whole body. It is made up of gaseous plasma and the time taken to complete one rotation increases with latitude. It is around 25 days at equator and 38 days at poles(it is judges by the location of sun spots)


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But I just had a thought coming to my mind, thinking about that in the mornings and evenings, we mostly see red light here, the higher end of the visible spectrum not getting through. It does get through, at least to some extent. You see a very blue sky when the Sun is at its reddest. That blue sky can give you a sunburn if you go skiing in the mountains ...


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The reddening of the sun has to do with Rayleigh scattering as the sun passes through more atmosphere. (see picture). This is in a sense, related to less energy but not the primary cause. The reason we get less solar energy per square meter is that the angle of the sun in the sky affects how spread out the light is. (see updated picture). Ignoring ...


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For a definition of the UV index and a rough discussion of influencing factors see e.g. https://en.wikipedia.org/wiki/Ultraviolet_index. You can compare the model shown there against actually measured data for the US: http://www.cpc.ncep.noaa.gov/products/stratosphere/uv_index/uv_annual.shtml. Both sources will support your statement that UV exposure in ...


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Do radio waves from the Sun reach Earth? Of course they do. It's just another form of electromagnetic radiation. If so, do they penetrate the atmosphere or are they reflected, absorbed, or scattered? That depends on frequency (or wavelength). The atmosphere reflects, absorbs, or scatters most incoming electromagnetic radiation. There's a window in ...


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Offhand I'm not sure where to find information about how much is absorbed, reflected and scattered, but the waves certainly do reach Earth, and some, at least, penetrate the atmosphere and end up in solar radio observatory detectors, otherwise we wouldn't have so many of them.


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Any shadow, either that of a small ball or a celestial body(especially spherical) consists of two parts umbra and penumbra. They are separated by a distinct border. Think of the moon(object) casting its shadow on the earth(screen) due to the sun(light source). Due to relative distances the moon's umbra is small, so only a small portion is in extreme darkness....


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The only difference is a minute change in brightness as the earth-sun distance changes from 147000 km (perihelion) to 152000 km (aphelion). Thus, at perihelion the sunlight is slightly more intense, and hence, so is the moonlight. At aphelion it's a little less intense, and at equinox it is about midway between those two. This difference is far smaller than ...


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You are probably referring to a Carrington Event where a large coronal mass ejection from the sun hits the Earth and creates massive disturbances in the magnetic field, with the result that things like the power grid are damaged by the induced currents. On July 23, 2012 a "Carrington-class" Solar Superstorm (Solar flare, Coronal mass ejection, Solar ...


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This timescale is not well defined. If you mean the time from initiation of cloud collapse to the beginning of hydrogen fusion, it is around 10 million years and determined by the Kelvin-Helmholtz timescale of the contracting protosun. If however you mean the timescale of cloud collapse to a revealed protostar with perhaps a disk around it, this is an order ...


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although the hint by @WetSavannaAnimal aka Rod Vance is sufficient to solve this problem but I would like to elaborate his hint. you know diameter of the sun, and distance from earth to sun. Now take a point, the rays emerging from two extremes of the sun and passing from this point will have maximum angle between them and that will set an upper limit on ...



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