Large Dust Grains Around Cometary Nuclei |
| |
| Authors: | A Molina F Moreno F J Jiménez-Fernández |
| |
| Institution: | (1) Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Granada, Avenida Severo Ochoa s/n, Granada, 18071, Spain;(2) Instituto de Astrofísica de Andalucía, CSIC, Camino Bajo de Huétor 50, Granada, 18008, Spain |
| |
| Abstract: | Large amounts of particles ejected from the nucleus surface are present in the vicinity of the cometary nuclei when comets
are near the Sun (at heliocentric distances ≤2 AU). The largest dust grains ejected may constitute a hazard for spatial vehicles.
We tried to obtain the bounded orbits of those particles and to investigate their stability along several orbital periods.
The model includes the solar and the cometary gravitational forces and the solar radiation pressure force. The nucleus is
assumed to be spherical. The dust grains are also assumed to be spherical, and radially ejected. We include the effects of
centrifugal forces owing to the comet rotation. An expression for the most heavy particles that can be lifted is proposed.
Using the usual values adopted for the case of Halley’s comet, the largest grains that can be lifted have a diameter about
5 cm, and the term due to the rotation is negligible. However, that term increases the obtained value for the maximum diameter
of the lifted grain in a significant amount when the rotation period is of the order of a few hours. |
| |
| Keywords: | Comets: general Comets: individual Interplanetary medium Meteoroids |
| 本文献已被 SpringerLink 等数据库收录！ |
|
