SPATIAL-DISTRIBUTION AND ORBITAL PROPERTIES OF INTERPLANETARY DUST ATHIGH-LATITUDES

Although the interplanetary dust cloud is assumed to be mainly concent rated in the ecliptic plane, there is a component of dust particles on highly inclined orbits that forms the out-of-ecliptic distribution. T he ULYSSES mission for the first time makes this component accessible to in-situ detection. Evidence for this dust component is also provide d from the analysis of the Zodiacal light brightness and especially fr om the spherical shape of the solar F - corona. An obvious source for an out-of-ecliptic dust population is the activity of comets on high e ccentric, highly inclined orbits. We discuss the dynamical conditions of particles under the influence of the radiation pressure when releas ed from the comet and discuss their input to the dust cloud based on b rightness analysis and in-situ results.