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A Newly Discovered Space Weather Phenomenon - Ion Plume

Written by : LAM Hok-yin       December 2007

Scientists and researchers gathered together last month (November 2007) in Ethiopia, Africa to discuss a newly discovered space weather phenomenon - ion plume. It can interfere with satellite transmission, airline navigation, radio communications and GPS signals.

Researchers discovered earlier that, when the sun exploded leading to coronal mass explosions or CME, a cloud of magnetized gas substance rushed towards the Earth, triggering a strong geomagnetic storm. On the electron density map for the ionosphere, about 85 to 600 km above ground, an ionized particle plume with a speed of about 1 kilometre per second can be seen (see diagram).

Electron density map (Source: NASA)


Scientists believe that the plume originates near Earth's magnetic equator. Africa is a good place to look for the answer, as a vast land area straddles the equator. However, due to a lack of instruments, detailed research and analysis will have to wait until an appropriate GPS network is established a few years down the road.


Science@NASA (


Last revision date: <19 Dec 2012>