Analysis on electrostatic levitation of lunar dust on the Moon's light side

The electrostatic charging process of lunar dust particulate on the moon's light side was modeled based on particle orbit theory and charging equation of space dusty plasma. Assuming a Maxiwellian distribution of photoelectron energies, the formulae of strength of vertical electric field as well as photoelectron density in a photoelectron sheath were derived. By means of the Newton's law of motion and electrostatic force equation, the dynamic model of electrostatic levitation for lunar dust grain on the moon's light side was derived. The dynamic behavior of levitating dust grain on the moon's light side was numerically analyzed. The results show that the basic controlling parameters for the onset of levitation and dynamics of the levitating particulate are the solar elevation angle and dust grain radius. The electrostatic levitation of lunar dust occurs during sunset and sunrise above the lunar surface. The smaller the dust grain size, the higher the vertical displacement of dust grain due to electrostatic levitation on the same environmental condition.