What is the difference between sunlight and solar wind?
Question:
Answer:
Solar wind is made of electrically charged electrons, protons, and helium nuclei (2 protons and 2 neutrons bound together). Sunlight is electromagnetic radiation and is not charged. Subatomic particles are easily shielded against, while more powerful electromagnetic radiation like gamma rays needs a bit more shielding.
I think the difference is that solar wind is the discharge of particles from the sun while sunlight is just the discharge of photons. Additionally, the earth's magnetic field repels solar wind.
Solar Wind
The plasma in the solar wind meeting the heliopause
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The plasma in the solar wind meeting the heliopause
A solar wind is a stream of charged particles (i.e., a plasma) which are ejected from the upper atmosphere of a star. When originating from stars other than the Earth's Sun, it is sometimes called a stellar wind.
It consists mostly of high-energy electrons and protons (about 1 keV) that are able to escape the star's gravity in part because of the high temperature of the corona and the high kinetic energy particles gain through a process that is not well understood at this time. Many phenomena are directly related to the solar wind, including: geomagnetic storms that can knock out power grids on Earth, auroras, why the tail of a comet always points away from the Sun, and the formation of distant stars.
While early models of the solar wind used primarily thermal energy to accelerate the material, by the 1960s it was clear that thermal acceleration alone cannot account for the high speed solar wind. Some additional acceleration mechanism is required, but is not currently known, but most likely relates to magnetic fields in the solar atmosphere.
Sunlight
Sunlight in the broad sense is the total spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the atmosphere, and the solar radiation is obvious as daylight when the Sun is above the horizon. This is usually during the hours known as day. Near the poles in summer, sunlight also occurs during the hours known as night and in the winter at the poles sunlight may not occur at any time. When the direct radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and heat. Radiant heat directly produced by the radiation of the sun is different from the increase in atmospheric temperature due to the radiative heating of the atmosphere by the sun's radiation.
The World Meteorological Organization defines sunshine as direct irradiance from the Sun measured on the ground of at least 120 W·m−2.
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