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mistergrinch
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Has anyone here looked at the physics of stellar engines? See http://en.wikipedia.org/wiki/Stellar_engine for an overview. In particular, I have done a simple calculation for the acceleration due to light pressure of a "Shkadov thruster", which is a reflective shell on one side of a star that stays in place due to the equilibrium of gravity and light pressure. My calculation for the acceleration this would produce on a star seems to be off by a factor of 4 from the Wikipedia example, which states:
Is anyone able to derive these numbers? Thanks!
For a star such as the Sun, with luminosity 3.85 × 10^26 W and mass 1.99 × 10^30 kg, the total thrust produced by reflecting half of the solar output would be 1.28 × 10^18 N. After a period of one million years this would yield an imparted speed of 20 m/s, with a displacement from the original position of 0.03 light-years. After one billion years, the speed would be 20 km/s and the displacement 34,000 light-years
Is anyone able to derive these numbers? Thanks!