Equatorial plasma bubble

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Equatorial plasma bubbles are an ionospheric phenomenon near the Earth's geomagnetic equator at night time. They affect radio waves by causing varying delays. They degrade the performance of GPS.[1]

Different times of the year and location have different frequencies of occurrence. In Northern Australia, the most common times are February to April and August to October, when a plasma bubble is expected every night.[1] Plasma bubbles have dimensions around 100 km.[2] Plasma bubbles form after dark when the sun stops ionising the ionosphere. The ions recombine, forming a lower density layer. This layer can rise through the more ionised layers above via convection, which makes a plasma bubble. The bubbles are turbulent with irregular edges.[2]

An equatorial plasma bubble could have affected the Battle of Shah-i-Kot by disabling communications from a communications satellite to a helicopter.[2]

References[edit]

  1. ^ a b Carter, Brett (5 December 2014). "Predicting daily space weather will help keep your GPS on target". Retrieved 5 December 2014. 
  2. ^ a b c Kelly, Michael (23 Sep 2014). "'Space bubbles' may have aided enemy in fatal Afghan battle". Retrieved 5 December 2014.