Space physicists study the ionosphere, a region of charged particles which exists between 80 and 1000 km above Earth's surface. The ionosphere is responsible for long distance radio communication. It also influences critical radio based services, such as communication satellite links and GPS navigation systems.
The ionosphere is highly influenced by solar radiation. It gains and loses charge, while forming distinct layers which move up and down in the atmosphere. Those changes occur slowly during Earth's 24 hour day. However, during a solar eclipse, dramatic changes occur on a minute by minute basis. Those rapid changes set the stage for experiments seeking to better understand ionospheric variation.
Some experiments involve the monitoring of ham radio signals - generally two people communicating, via short wave radio, over paths far beyond their line of sight. How far their signals travel and how many signals are present at any one time provides insight into the state of the ionosphere - for instance, its height, density and its dynamics.
The Festivals of Eclipse Ionospheric Science are being held during the October 2023 and April 2024 solar eclipses to encourage hams to use their equipment just before, during and after the eclipse events. Ham radio activity will provide researchers with a rich set of data regarding the ionosphere's reaction to the rapid changes in solar radiation due to the eclipse.
