Portal:Jupiter/Radiation astronomy/8

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Cosmic rays[edit | edit source]

Schematic illustrates how Jupiter's unusually frequent and spectacular auroral activity is produced. Credit: M. Weiss.{{fairuse}}
This is the Pioneer 10 - Helium Vector Magnetometer. Credit: NASA.

Jupiter's strong, rapidly rotating magnetic field (light blue lines in the figure) generates strong electric fields in the space around the planet. Charged particles (white dots), "trapped in Jupiter's magnetic field, are continually being accelerated (gold particles) down into the atmosphere above the polar regions, so auroras are almost always active on Jupiter. Electric voltages of about 10 million volts, and currents of 10 million amps - a hundred times greater than the most powerful lightning bolts - are required to explain the auroras at Jupiter's poles, which are a thousand times more powerful than those on Earth. On Earth, auroras are triggered by solar storms of energetic particles, which disturb Earth's magnetic field. As shown by the swept-back appearance in the illustration, gusts of particles from the Sun also distort Jupiter's magnetic field, and on occasion produce auroras."[1]

"The helium vector magnetometer [in the image on the left] measures the fine structure of the interplanetary field, maps the Jovian field, and provides field measurements to evaluate solar wind interaction with Jupiter. The magnetometer operates in any one of eight different ranges, the lowest of which covers magnetic fields from ±0.01 to ±4.0 gamma; the highest fields up to ±140,000 gamma; i.e., ±1.4 Gauss."[2]

References[edit | edit source]

  1. X-ray: NASA/CXC/MSFC/R.ElsnerExpression error: Unrecognized word "etal". (2 March 2005). Jupiter: Chandra Probes High-Voltage Auroras on Jupiter. Cambridge, Massachusetts: Harvard-Smithsonian Center for Astrophysics. http://chandra.harvard.edu/photo/2005/jupiter/. Retrieved 11 July 2012. 
  2. Edward J. Smith (6 August 2004). Magnetic Fields. Washington, DC USA: NASA. http://history.nasa.gov/SP-349/ch4.htm. Retrieved 17 August 2016.