Solar wind and the motion of dust grains
Article first published online: 3 FEB 2012
© 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS
Monthly Notices of the Royal Astronomical Society
Volume 421, Issue 2, pages 943–959, April 2012
How to Cite
Klačka, J., Petržala, J., Pástor, P. and Kómar, L. (2012), Solar wind and the motion of dust grains. Monthly Notices of the Royal Astronomical Society, 421: 943–959. doi: 10.1111/j.1365-2966.2012.20321.x
- Issue published online: 16 MAR 2012
- Article first published online: 3 FEB 2012
- Accepted 2011 November 28. Received 2011 November 10; in original form 2011 July 7
- celestial mechanics;
- solar wind;
- interplanetary medium;
- zodiacal dust
In this paper, we investigate the action of solar wind on an arbitrarily shaped interplanetary dust particle. The final relativistically covariant equation of motion of the particle also contains the change of the particle’s mass. The non-radial solar wind velocity vector is also included. The covariant equation of motion reduces to the Poynting–Robertson effect in the limiting case when a spherical particle is treated, when the speed of the incident solar wind corpuscles tends to the speed of light and when the corpuscles spread radially from the Sun. The results of quantum mechanics have to be incorporated into the physical considerations, in order to obtain the limiting case.
If the solar wind affects the motion of a spherical interplanetary dust particle, then . Here, p′in and p′out are the incoming and outgoing radiation momenta (per unit time), respectively, measured in the proper frame of reference of the particle, and and are the solar wind pressure and the total scattering cross-sections, respectively.
An analytical solution of the derived equation of motion yields a qualitative behaviour consistent with numerical calculations. This also holds if we consider a decrease of the particle’s mass. Using numerical integration of the derived equation of motion, we confirm our analytical result that the non-radial solar wind (with a constant value of angle between the radial direction and the direction of the solar wind velocity) causes outspiralling of the dust particle from the Sun for large values of the particle’s semimajor axis. The non-radial solar wind also increases the time the particle spirals towards the Sun. If we consider the periodical variability of the solar wind with the solar cycle, then there are resonances between the particle’s orbital period and the period of the solar cycle.