To understand the end-to-end connection of the Sun to the Earth, we must understand each link in the chain. The purpose of Solar Connections is to conduct an orderly, systematic study, that will give us the scientific basis to understand the whole chain.
When we examine the Solar Connection chain closely, we find an intricate picture. At the Sun, energy is released from the nuclear furnace at the Sun's core. This energy heats and drives processes in the Sun's atmosphere that result in explosive energy releases, such as solar flares and coronal mass ejections (CMEs).
The hot, gusty, electrically charged, coronal gas (the solar wind) flows at speeds of 200 to 1000 km/sec and carries with it a magnetic field rooted in the Sun. The solar wind, and even hotter, faster charged particles accelerated in flares and CMEs, encounter the Earth's magnetosphere (and those of other planets). This high-speed flow of plasma couples to the magnetosphere through a variety of paths at both polar and equatorial latitudes and in the extended downstream magnetotail.
The magnetosphere provides conduits through which millions of megawatts of energy carried via corpuscular radiation are eventually dumped into the ionosphere and upper atmosphere. This is the dominant energy input to the upper atmosphere. The solar wind also causes changes in the intensity of galactic cosmic rays at Earth, which are a major factor governing the electrical conductivity of the atmosphere.
Electromagnetic radiation, especially a steady bath of ultraviolet (UV) radiation and variable levels of X-ray, gamma ray, and UV radiation from solar active regions, illuminates and affects all layers of the atmosphere directly.
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Solar Connections: A Science Initiative for NASA Space Physics
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