enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Ionosphere - Wikipedia

    en.wikipedia.org/wiki/Ionosphere

    Relationship of the atmosphere and ionosphere. The ionosphere (/ aɪ ˈ ɒ n ə ˌ s f ɪər /) [1] [2] is the ionized part of the upper atmosphere of Earth, from about 48 km (30 mi) to 965 km (600 mi) above sea level, [3] a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar ...

  3. List of musical symbols - Wikipedia

    en.wikipedia.org/wiki/List_of_musical_symbols

    Musical symbols are marks and symbols in musical notation that indicate various aspects of how a piece of music is to be performed. There are symbols to communicate information about many musical elements, including pitch, duration, dynamics, or articulation of musical notes; tempo, metre, form (e.g., whether sections are repeated), and details about specific playing techniques (e.g., which ...

  4. Very low frequency - Wikipedia

    en.wikipedia.org/wiki/Very_low_frequency

    The conductive ionosphere and the conductive Earth form a horizontal "duct" a few VLF wavelengths high, which acts as a waveguide confining the waves so they don't escape into space. The waves travel in a zig-zag path around the Earth, reflected alternately by the Earth and the ionosphere, in transverse magnetic (TM) mode.

  5. Ionosonde - Wikipedia

    en.wikipedia.org/wiki/Ionosonde

    An ionosonde, or chirpsounder, is a special radar for the examination of the ionosphere. The basic ionosonde technology was invented in 1925 by Gregory Breit and Merle A. Tuve [ 1 ] and further developed in the late 1920s by a number of prominent physicists, including Edward Victor Appleton .

  6. Radio broadcasting - Wikipedia

    en.wikipedia.org/wiki/Radio_broadcasting

    AM transmissions cannot be ionospheric propagated during the day due to strong absorption in the D-layer of the ionosphere. In a crowded channel environment, this means that the power of regional channels which share a frequency must be reduced at night or directionally beamed in order to avoid interference, which reduces the potential ...

  7. Ionospheric pierce point - Wikipedia

    en.wikipedia.org/wiki/Ionospheric_pierce_point

    Here R is the mean Earth radius, H is the mean height of the ionosphere shell. The IPP or Ionospheric Pierce Point is the altitude in the ionosphere where electron density is greatest. [1] These points can change based on factors like time of day, solar activity, and geographical location, which all influence ionospheric conditions. [2]

  8. Dark Matter May Not Be Invisible After All. This Discovery ...

    www.aol.com/dark-matter-may-not-invisible...

    The ionosphere is an ideal place to look for the telltale signs of this particular form of dark matter, the scientists explain, because we already spend a lot of time and resources doing studies ...

  9. Ionospheric absorption - Wikipedia

    en.wikipedia.org/wiki/Ionospheric_absorption

    ISAB is only a factor in the period of the day where radio signals travel through the portion of the ionosphere facing the Sun. The solar wind and radiation cause the ionosphere to become charged with electrons in the first place. At night, the atmosphere becomes drained of its charge, and radio signals can go much farther with less loss of signal.