TechnicalSRP
Solar Radiation Pressure
The small but persistent force exerted on a spacecraft by sunlight, a significant orbital perturbation for high-altitude and large-area satellites.
Solar radiation pressure is the momentum transferred by photons striking a spacecraft's surfaces. Although tiny, it acts continuously and matters for precise orbit determination, especially for satellites with large solar arrays or at high altitudes where atmospheric drag is negligible.
It must be modelled in conjunction assessment and station-keeping, and it can be deliberately exploited by solar sails and for passive attitude effects.