Astronomy
Sailing on sunlight
Tilt a reflecting sail. Resolve photon pressure into radial and tangential thrust and find the angle that gives the strongest sideways push.

The model and its limits
Perfectly reflecting flat sail at 1 AU. Force vectors and a short constant-acceleration displacement are calculated; no full orbit, wrinkling or thermal limits.
Equations used in the module
Equations a = 2S cos²α/(c σ); a_r = a cos α; a_t = a sin α


