Space plasmas Reference Libraries

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How Solar Cycles Impact Our Weather Here On Earth
2013-01-13 09:10:34

Solar cycles: what are they and why should we care about them? Solar cycles are made up of what are known as solar minimums (min) and solar maximums (max). We refer to a solar min at the time when the sun is not active with many sunspots, while a solar max is just the opposite when we see a large increase in sunspot activity. So how long do solar cycles last? Typically they run on what is...

Solar Physics
2012-05-02 19:16:53

Solar Physics is a journal for solar and solar-stellar research and the study of solar terrestrial physics. Founded in 1967 by solar physicist Cornelis de Jager and publisher D. Reidel, the journal treats all aspects of solar physics, ranging from the internal structure of the Sun and its evolution, to outer corona and solar wind in interplanetary space. Solar Physics has four more than...

Radio Atmospheric Signal
2009-07-21 16:45:53

A Radio Atmospheric signal (sometimes referred to as Sferic or Spheric), is a broadband electromagnetic impulse that occurs during atmospheric lightning discharges. Sferics spread out from the lightning source and can be received thousands of miles away. A sferic, depending on atmospheric conditions, may extend anywhere from a few kHz to several tens of kHz. Sferics from far reaching storms,...

Alfvn Hannes
2013-03-16 00:00:00

Hannes Olof Gösta Alfvén (May 30, 1908 - April 2, 1995) was a Swedish plasma physicist born in Norrköping, Sweden. Alfvén received his PhD from the University of Uppsala in 1934. His thesis was titled "Investigations of the Ultra-short Electromagnetic Waves." He was originally trained as an electrical power engineer and later moved on to research and teaching in the fields of plasma...

Ring Current
2004-10-19 04:45:44

Ring Current -- A ring current is an electric current carried by charged particles trapped in a planet's magnetosphere. It is caused by the longitudinal drift of energetic (10-200 keV) particles. Earth's Ring Current Earth's ring current is responsible for geomagnetic storms. The ring current system consists of a band, at a distance of 3-5 RE(1), which lies in the equatorial plane and...

Supernova Remnant
2004-10-19 04:45:42

Supernova Remnant -- A supernova remnant (SNR) is made up of the materials left behind by the gigantic explosion of a star in a supernova. There are two possible routes to this end: either a massive star may cease to generate fusion energy in its core, and collapse inward under the force of its own gravity, or a white dwarf star may accumulate material from a companion star until it reaches...

Stellar Evolution
2004-10-19 04:45:42

Stellar Evolution -- Stellar evolution is the process of formation, life, and death of stars. It is one of the major topics of cosmogony. Star Birth and Life A star starts out as an enormous cloud of gas and dust many light-years across. Star formation begins when the cloud begins to condense under its own gravity. The processes that initiate this contraction are not fully understood....

2004-10-19 04:45:42

Star -- A star is a self-gravitating sphere of plasma in hydrostatic equilibrium that generates energy in its interior through the process of nuclear fusion. Energy from this process radiates into space as electromagnetic radiation and neutrinos. Star formation and evolution As learned by star formation astronomers, stars are born in molecular clouds, regions of higher density of...

Planetary Nebula
2004-10-19 04:45:42

Planetary Nebula -- A planetary nebula is an astronomical object that usually appears nebulous and disk-like in low-resolution observations. Because of this appearance, similar to the appearance of planets in early observations, the "planetary" adjective was attached and has since been retained for historical consistency. According to current observations and models, planetary nebulae...

2004-10-19 04:45:42

Photosphere -- The photosphere of an astronomical object is the region at which the optical depth becomes one. In other words, the photosphere is the place where an object stops being transparent. It is typically used to describe the Sun or another star. Because stars are large balls of gas, they have no solid surface. However, there is a depth at which the gas stops being transparent to...

Word of the Day
  • A large punch-bowl of the eighteenth century, usually of silver and with a movable rim, and decorated with flutings and a scalloped edge. It was also used for cooling and carrying wine-glasses.
  • A kind of cotton handkerchief having white spots on a colored ground, the spots being produced by a chemical which discharges the color.
This word is possibly named after Monteith (Monteigh), 'an eccentric 17th-century Scotsman who wore a cloak scalloped at the hem.'