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It is approximately 80%, which is a realistic maximum for the clear Rayleigh sky during day time. The video thus begins when the sun is slightly above the horizon and at an azimuth of 120°. The sky is highly polarized in the effective North-Zenith-South plane. This is slightly offset because the sun's azimuth is not due East.
Rayleigh scattering causes the blue color of the daytime sky and the reddening of the Sun at sunset. Rayleigh scattering (/ ˈ r eɪ l i / RAY-lee) is the scattering or deflection of light, or other electromagnetic radiation, by particles with a size much smaller than the wavelength of the radiation.
For an observer on the ground, the amount of the arc that is visible depends on the height of the sun above the horizon. It is a full semicircle with an angular radius of 42° when the sun is at the horizon. But as the sun rises in the sky, the arc grows smaller and ceases to be visible when the sun is more than 42° above the horizon.
The blue sky spectrum contains light at all visible wavelengths with a broad maximum around 450–485 nm, the wavelengths of the color blue. Diffuse sky radiation is solar radiation reaching the Earth's surface after having been scattered from the direct solar beam by molecules or particulates in the atmosphere.
The radio horizon is the locus of points at which direct rays from an antenna are tangential to the surface of the Earth. If the Earth were a perfect sphere without an atmosphere, the radio horizon would be a circle. The radio horizon of the transmitting and receiving antennas can be added together to increase the effective communication range.
Rayleigh scattering makes the sky appear blue in the daytime; the more aerosols there are, the less blue or whiter the sky appears. In many areas, most particularly in urban areas, aerosol scattering dominates, due to the heavy aerosol loading caused by modern industrial activity, power generation, farming and transportation.
In probability theory and statistics, the Rayleigh distribution is a continuous probability distribution for nonnegative-valued random variables. Up to rescaling, it coincides with the chi distribution with two degrees of freedom .
In radio communication, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and reflection from water bodies and terrestrial objects such as mountains and buildings.