* Astronomy

 Egyptian invents a spacecraft propulsion device

A 19-year-old Egyptian university student called Aisha Mustafa has invented a propulsion device intended to offer spacecrafts a new method and cheaper means of energy consumption.
The propulsion device promises chances of using quantum physics and chemical reactions in artificial satellites
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Hypothetical Differential Sail: Analogous to the principles of an ideal radiometer vane, a net difference in radiation pressure exists across the reflecting and absorbing sides. It is assumed that space contains a background of some form of isotropic medium (like the vacuum fluctuations or Cosmic Background Radiation) that is constantly impinging on all sides of the sail.
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