Light, Sound and Waves

Gassy refraction

Stories from Physics for 11-14 14-16 IOP RESOURCES

A cloud of gas in the Milky Way was observed refracting the radio wave emissions of a distant quasar, to form multiple images of the object. This rare scattering event in 2008-2009 lasted for around 50 days as the gas cloud moved through the line of sight of the quasar.


can be represented by Ray Diagrams
formalised by Snell's Law
has the special case Total Internal Reflection
is used in analyses relating to Lens
can be analysed using the quantity Refractive Index
can be exhibited by Progressive Wave
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