ON THE STABILITY OF THE ZODIACAL CLOUD

The problem of the stability of the zodiacal cloud is scrutinized. The central idea of the paper sticks in the theoretical treatment of the action of the solar electromagnetic radiation on small interplanetary dust particles (IDPs). It is suggested that the virtual problem of the (in-)stability of the zodiacal cloud originated from the physically i ncorrect application of the Poynting-Robertson effect on IDPs. Real pa rticles are not of spherical shape and so the braking acceleration is not proportional to -v/c. Depending on the shape (and other optical pr operties) of the particle, also spiralling outward from the Sun may oc cur.