This project must be done by individuals.
Joe Aerospace decides to make a "solar sail" for his private spaceship. The "sail" uses radiation pressure from the Sun to move a ship, in the same way that a regular sail uses pressure from the wind. Joe uses ordinary aluminum foil (Reynolds Wrap or the equivalent) for his sail.
The Sun radiates a great deal of energy per second; look for "solar luminosity" in a reference book or on the Interwebs. Assume that all of this energy is emitted as photons of wavelengths 550 nanometers -- greenish-yellow light. These photons each have
energy E = 3.61 x 10^(-19) Joules momentum p = 1.21 x 10^(-27) kg*m/s
Joe's sail is a square, 100 meters on a side, located at the Earth's distance from the Sun. He orients it so that photons strike it face-on and bounce back towards the Sun.
This page maintained by Michael Richmond. Last modified Nov 1, 2004.
Copyright © Michael Richmond. This work is licensed under a Creative Commons License.