Radio wave by radio receivers, using antennas. Radio waves are very widely used in modern technology for fixed and mobile radio communication, broadcasting, radar and other navigation systems, communications satellites, wireless computer networks and many other applications. Different frequencies of radio waves have different propagation characteristics in the Earth's atmosphere; long waves can diffract around obstacles like mountains and follow the contour of the earth (ground waves), shorter waves can reflect off the ionosphere and return to earth beyond the horizon (skywaves), while much shorter wavelengths bend or diffract very little and travel on a line of sight, so their propagation distances
Atmospheric escape brighter than it is now, making it hot enough for Earth to lose enough hydrogen to space to cause it to lose all of its water (See Future of Earth#Loss of oceans). Atmospheric escape Atmospheric escape is the loss of planetary atmospheric gases to outer space. A number of different mechanisms can be responsible for atmospheric escape, operating at different time scales; the most prominent is Jeans Escape, named after British astronomer Sir James Jeans, who described the process of atmospheric loss to the molecular kinetic energy. The relative importance of each loss process is a function of the planet's