Ioniseerimiskõrgus

Ioniseerimiskõrgus, also known as the ionosphere, is a region of Earth's upper atmosphere, roughly 50 to 600 kilometers above the surface. It is characterized by the presence of ions and free electrons, which are created by the ionization of atmospheric gases due to solar radiation. The ionosphere plays a crucial role in radio communication, as it reflects and refracts radio waves, allowing long-distance communication.

The ionosphere is divided into several layers based on their ionization characteristics and altitude. The D layer, closest to Earth, is the least dense and is primarily ionized by solar radiation during the day. The E layer, located above the D layer, is ionized by both solar radiation and cosmic rays. The F layer, the highest and most dense, is further divided into the F1 and F2 layers. The F2 layer is particularly important for long-distance radio communication, as it can reflect radio waves back to Earth.

The ionosphere's properties are influenced by solar activity, which varies over an 11-year cycle. During periods of high solar activity, the ionosphere becomes more ionized, which can disrupt radio communications. Conversely, during periods of low solar activity, the ionosphere is less ionized, which can improve radio communications.

The ionosphere is also home to the auroras, which are natural light displays that occur when charged particles from the sun interact with Earth's magnetic field and the ionosphere. These particles collide with atmospheric gases, causing them to emit light and creating the beautiful displays of the auroras.