When the solar wind reaches Earth, as we saw, it causes Earth’s magnetosphere to contract and then expand after the solar wind passes by. These changes can cause (usually mild) electromagnetic disturbances on Earth. More serious are solar flares, which shower the upper atmosphere of Earth with X-rays, energetic particles, and intense ultraviolet radiation. The X-rays and ultraviolet radiation can ionize atoms in Earth’s upper atmosphere, and the freed electrons can build up a charge on the surface of a spacecraft. When this static charge discharges, it can damage the electronics in the spacecraft—just as you can receive a shock when you walk across a carpet in your stocking feet in a dry climate and then touch a light switch or some other metal object. Most disruptive are coronal mass ejections. A CME is an erupting bubble of tens of millions of tons of gas blown away from the Sun into space. When this bubble reaches Earth a few days after leaving the Sun, it heats the ionosphere, which expands and reaches farther into space. As a consequence, friction between the atmosphere and spacecraft increases, dragging satellites to lower altitudes.

Man's near‐space environment is dominated by energy from the sun, which arrives in the vicinity of the earth in two forms: as electromagnetic radiation and as the plasma flow of the solar wind. This energy interacts with the earth's magnetosphere and atmosphere in a variety of ways. The study of these interactions has been a major goal of NASA's Explorer programs. Most of the solar electromagnetic energy lies in the visible region of the spectrum and passes directly through the upper atmosphere. However, part of the solar energy in the ultraviolet interacts strongly with the upper atmosphere and produces the ionospheric and ozone layers. Understanding how this radiation controls the ionosphere and thermosphere has been a primary objective of the Atmosphere Explorer program.

If it loses an electron, it becomes a positively charged ion, called a cation. If it gains an electron, it becomes a negatively charged ion, called an anion. To take away an electron from an atom or molecule, energy is needed. This energy is called ionization energy or ionization potential. Some atoms need a lot of energy to lose an electron, while others need much less.[2] On the other hand, some atoms easily attract and accept extra electrons. This ability is called their electron affinity.[3] Sometimes ionization only removes one electron, but in very energetic places, like inside stars or lightning, it can remove two or more electrons, making ions with stronger charges. This can happen in plasmas, which are hot gases filled with charged particles.[4] Ionization happens naturally in many places around us. For example, in the upper part of Earth’s atmosphere, sunlight contains strong ultraviolet (UV) rays that can knock electrons off gas molecules. This creates a special layer called the ionosphere, which helps radio signals travel long distances and plays a role in space weather.[5] Inside the body, ionization is also important.

charged. ionized layers. . Layers of charged particles existing in the upper reaches of the atmosphere as a result of solar radiation . ionosphere . , n. 1

outer space. It shields the surface from most meteoroids and ultraviolet solar radiation, reduces diurnal temperature variation – the temperature extremes The atmosphere of Earth consists of a layer of mixed gas (commonly referred to as air) that is retained by gravity, surrounding the Earth's surface. It contains variable quantities of suspended aerosols and particulates that create weather features such as clouds and hazes. The atmosphere serves as a protective buffer between the Earth's surface and outer space. It shields the surface from most me The ozone layer is contained within the stratosphere. In this layer ozone reaches a peak concentration of 15 parts per million at an altitude of 32 km (20 mi), which is much higher than in the lower atmosphere but still very small compared to the main components of the atmosphere. It is mainly located in the lower portion of the stratosphere from about 15–35 km (9.3–21.7 mi), though the thickness varies seasonally and geographically. About 90% of the ozone in Earth's atmosphere is contained in the stratosphere. The ionosphere is a region of the atmosphere that is ionized by solar radiation. It plays a significant role in auroras, airglow, and space weather phenomenon. During daytime hours, it stretches from 50 to 1,000 km (31 to 621 mi) and includes the mesosphere, thermosphere, and parts of the exosphere. However, ionization in the mesosphere largely ceases during the night. The ionosphere forms the inner edge of the plasmasphere – the inner magnetosphere. It has practical importance because it influences, for example, radio propagation on Earth. The homosphere and heterosphere are defined by whether the atmospheric gases are well mixed. The surface-based homosphere includes the troposphere, stratosphere, mesosphere, and the lowest part of the thermosphere, where the chemical composition of the atmosphere does not depend on molecular weight because the gases are mixed by turbulence. This relatively homogeneous layer ends at the turbopause found at about 100 km (62 mi; 330,000 ft), the very edge of space itself as accepted by the FAI, which places it about 20 km (12 mi; 66,000 ft) above the mesopause. Above this altitude lies the heterosphere, which includes the exosphere and most of the thermosphere. Here, the chemical composition varies with altitude. This is because the distance that particles can move without colliding with one another is large compared with the size of motions that cause mixing. This allows the gases to stratify by molecular weight, with the heavier ones, such as oxygen and nitrogen, present only near the bottom of the heterosphere. The upper part of the heterosphere is composed almost completely of hydrogen, the lightest element. The…