If light has no mass, how can a solar sail be propelled?
How can light provide momentum to solar sails if its mass is zero?
How can massless particles (photons) have momentum? How can a photon not have mass but still have momentum? Physics: Why don’t photons have mass? How can a photon have no mass when E=mc^2? How does the earth orbit the sun without losing energy? Does light have kinetic energy? How is it possible that a photon is massless? How is it possible for sun to have more energy than Lightning? Given that photons have no mass and the speed of light cannot be exceeded, could there be a negative mass that exceeds the speed of light? Why don't photons have mass? What is mass of the sun? The planets revolve around the sun without losing energy when gravitational force is acting on them .why? What is the mass of the Sun? How can a photon exist if it is massless? How does the top of a commercial solar tower not melt when all the mirrors are pointing light at it? How powerful is the sun? Does Light attract Light? Light is energy therefore E=mc^2. If it has mass it has gravity? Can we use  kinetic energy of cosmic rays as energy resource? What is the mass of our sun? What does it mean for a particle like a photon to have a rest-mass of zero? Do massless particles have to travel at the speed of light? Does energy have mass or light (as in light beam) have mass? Does light have mass? What would happen if a red giant with 700x the mass of the sun were to start rotating at the speed of light just as it started collapsing? How can photons have no mass and yet still have energy given that [math]E=mc^2[/math]? What is the principle behind why celestial objects like planets do not collapse into the gravity of the sun but revolve around it? Does a moving photon have mass? If the center of a uniformity dense sphere experiences zero gravity, how come the centers of stars and planets are such high pressure enviornments? How is the motion of stars similar to the motion of the sun? What is the Solar energy?