Solar wind dominance over the Poynting-Robertson effect in secular orbital evolution of dust particles

Properties of the solar wind are discussed and applied to the effect of the wind on motion of bodies in the Solar system. The velocity density function for the solar wind constituents is given by the kappa-distribution. The relevant contributions to the solar wind action contain also the sputtering and reflection components in addition to direct impact. The solar wind effect is more important than the action of the solar electromagnetic radiation, as for the secular orbital evolution. The acceleration of a body under the action of the solar radiation, electromagnetic and corpuscular, is proportional to is the dimensionless efficiency factor of the radiation pressure, v is the body's velocity at the position vector r with respect to the Sun, c is the speed of light and eta(1) a parts per thousand E 1.1, eta(2) a parts per thousand E 1.4. The dimensionless cross-section the dust grain presents to wind pressure is about 4.7, while the conventional value is 1.0.