Analysis of Ulysses data: Radiation pressure effects on dust particles

¹ SAP AG, Neurottstrasse 16, 69190 Walldorf, Germany
² Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
³ Hawaii Institute of Geophysics and Planetology, HIGP, University of Hawaii, 1680 East West Road, Honolulu, HI 96822, USA

Corresponding author: A. Wehry, andreas.wehry@sap.com

Received: 3 November 2003
Accepted: 18 February 2004

Abstract

The objective of this paper is to illustrate the influence of the radiation pressure and the electromagnetic force on dust particles in interplanetary space. Between 1990 and 2001 62 so-called β-meteoroids (β describes the ratio of the radiation pressure force to gravity) were detected as dust particles coming from the inner solar system on hyperbolic orbits. 24 of them were detected shortly after the launch of Ulysses within the ecliptic and 38 of them were recorded primarily passing the Solar poles. Furthermore high speed particles not coming from the direction of the Sun were ejected from the solar system by electromagnetic forces. For the time period until the end of 2008 the effective area for particles coming from the direction of the Sun has been determined. The particles' perihelion distances indicated that they originated within a region of from the Sun. For the second orbit of Ulysses the flux of β-meteoroids was determined using the same method as during its first revolution. Because of the more defocusing phase during the first orbit of Ulysses the production rate of β-meteoroids has been estimated to be nearly twice of that for the second revolution. On the other hand, an imbalance of the identified β-meteoroids between the north and south pole could not be explained by the solar cycle.