Ionosphere this process can occur. Due to the ability of ionized atmospheric gases to refract high frequency (HF, or shortwave) radio waves, the ionosphere can reflect radio waves directed into the sky back toward the Earth. Radio waves directed at an angle into the sky can return to Earth beyond the horizon. This technique, called "skip" or "skywave" propagation, has been used since the 1920s to communicate at international or intercontinental distances. The returning radio waves can reflect off the Earth's surface into the sky again, allowing greater ranges to be achieved with multiple hops. This communication method is variable and
Night Waves Night Waves Night Waves was a radio programme broadcast on BBC Radio 3. The BBC described it as "Radio 3's flagship arts and ideas programme". "The Guardian" said in May 2010 "...the king of radio arts programmes is undoubtedly "Night Waves", a programme so clever that it regularly makes me stand still and listen, usually halfway to the dishwasher with a plate in my hand...It's the desire to untangle arguments, to lift up their corners and see what lurks there. There's a gleeful range of references too...and a relish for intelligent debate." It was broadcast every Monday to Thursday evening,