Orbital evolution under action of fast interstellar gas flow

Orbital evolution of an interplanetary dust particle under action of an interstellar gas flow is investigated. Secular time derivatives of the particle orbital elements, for arbitrary orbit orientation, are presented. An important result concerns secular evolution of semi-major axis. Secular semi-major axis of the particle on a bound orbit decreases under the action of fast interstellar gas flow. Possible types of evolution of other Keplerian orbital elements are discussed. The paper compares influences of the Poynting-Robertson effect, the radial solar wind and the interstellar gas flow on dynamics of the dust particle in outer planetary region of the Solar System and beyond it, up to 100 AU. Evolution of putative dust ring in the zone of the Edgeworth-Kuiper belt is studied. Also non-radial solar wind and gravitational effect of major planets may play an important role. Low inclination orbits of micron-sized dust particles in the belt are not stable due to fast increase of eccentricity caused by the interstellar gas flow and subsequent planetary perturbations - the increase of eccentricity leads to planet crossing orbits of the particles. Gravitational and non-gravitational effects are treated in a way which fully respects physics. As a consequence, some of the published results turned out to be incorrect. Moreover, the paper treats the problem in a more general way than it has been presented up to now. The influence of the fast interstellar neutral gas flow might not be ignored in modeling of evolution of dust particles beyond planets.Comment: 12 pages, 7 figure

Motion of dust in mean-motion resonances with planets

Effect of stellar electromagnetic radiation on motion of spherical dust particle in mean-motion orbital resonances with a planet is investigated. Planar circular restricted three-body problem with the Poynting-Robertson (P-R) effect yields monotonous secular evolution of eccentricity when the particle is trapped in the resonance. Elliptically restricted three-body problem with the P-R effect enables nonmonotonous secular evolution of eccentricity and the evolution of eccentricity is qualitatively consistent with the published results for the complicated case of interaction of electromagnetic radiation with nonspherical dust grain. Thus, it is sufficient to allow either nonzero eccentricity of the planet or nonsphericity of the grain and the orbital evolutions in the resonances are qualitatively equal for the two cases. This holds both for exterior and interior mean-motion orbital resonances. Evolutions of longitude of pericenter in the planar circular and elliptical restricted three-body problems are shown. Our numerical integrations suggest that any analytic expression for secular time derivative of the particle's longitude of pericenter does not exist, if a dependence on semi-major axis, eccentricity and longitude of pericenter is considered (the P-R effect and mean-motion resonance with the planet in circular orbit is taken into account). Change of optical properties of the spherical grain with the heliocentric distance is also considered. The change of the optical properties: i) does not have any significant influence on secular evolution of eccentricity, ii) causes that the shift of pericenter is mainly in the same direction/orientation as the particle motion around the Sun. The statements hold both for circular and noncircular planetary orbits.Comment: 22 pages, 12 figure

Meteor showers of comet C/1917 F1 Mellish

December Monocerotids and November Orionids are weak but established annual meteor showers active throughout November and December. Analysis of a high quality orbits subset of the SonotaCo video meteor database shows that the distribution of orbital elements, geocentric velocity and also the orbital evolution of the meteors and potential parent body may imply a common origin for these meteors coming from the parent comet C/1917 F1 Mellish. This is also confirmed by the physical properties and activity of these shower meteors. An assumed release of meteoroids at the perihelion of the comet in the past and the sky-plane radiant distribution reveal that the December Monocerotid stream might be younger than the November Orionids. A meteoroid transversal component of ejection velocity at the perihelion must be larger than 100 m/s. A few authors have also associated December Canis Minorids with the comet C/1917 F1 Mellish. However, we did not find any connection.Comment: 11 pages, 11 figures and 5 table

Radial migration of the Sun in galactic disk

Physics of the gravitational effect of the galactic bar and spiral structure is presented. Physical equations differ from the conventionally used equations. Application to the motion of the Sun is treated. The speed of the Sun is taken to be consistent with the Oort constants. Galactic radial migration of the Sun is less than +- 0.4 kpc for the four-armed spiral structure. The Sun remains about 75 % of its existence within galactocentric distances (7.8 - 8.2) kpc and the results are practically independent on the spiral structure strength. Thus, the radial distance changes only within 5 % from the value of 8 kpc. Galactic radial migration of the Sun is less than +- (0.3 - 1.2) kpc, for the two-armed spiral structure. The Sun remains (29 - 95) % of its existence within galactocentric distances (7.8 - 8.2) kpc and the results strongly depend on the spiral structure strength and the angular speed of the spiral arms. The radial distance changes within (3.8 - 15.0) % from the value of 8 kpc. If observational arguments prefer relevant radial migration of the Sun, then the Milky Way is characterized by the two-arm spiral structure.Comment: 9 page

Surface electrons at plasma walls

In this chapter we introduce a microscopic modelling of the surplus electrons on the plasma wall which complements the classical description of the plasma sheath. First we introduce a model for the electron surface layer to study the quasistationary electron distribution and the potential at an unbiased plasma wall. Then we calculate sticking coefficients and desorption times for electron trapping in the image states. Finally we study how surplus electrons affect light scattering and how charge signatures offer the possibility of a novel charge measurement for dust grains.Comment: To appear in Complex Plasmas: Scientific Challenges and Technological Opportunities, Editors: M. Bonitz, K. Becker, J. Lopez and H. Thomse

Influence of fast interstellar gas flow on dynamics of dust grains

The orbital evolution of a dust particle under the action of a fast interstellar gas flow is investigated. The secular time derivatives of Keplerian orbital elements and the radial, transversal, and normal components of the gas flow velocity vector at the pericentre of the particle's orbit are derived. The secular time derivatives of the semi-major axis, eccentricity, and of the radial, transversal, and normal components of the gas flow velocity vector at the pericentre of the particle's orbit constitute a system of equations that determines the evolution of the particle's orbit in space with respect to the gas flow velocity vector. This system of differential equations can be easily solved analytically. From the solution of the system we found the evolution of the Keplerian orbital elements in the special case when the orbital elements are determined with respect to a plane perpendicular to the gas flow velocity vector. Transformation of the Keplerian orbital elements determined for this special case into orbital elements determined with respect to an arbitrary oriented plane is presented. The orbital elements of the dust particle change periodically with a constant oscillation period or remain constant. Planar, perpendicular and stationary solutions are discussed. The applicability of this solution in the Solar system is also investigated. We consider icy particles with radii from 1 to 10 micrometers. The presented solution is valid for these particles in orbits with semi-major axes from 200 to 3000 AU and eccentricities smaller than 0.8, approximately. The oscillation periods for these orbits range from 10^5 to 2 x 10^6 years, approximately.Comment: 22 pages, 3 figures; Accepted for publication in Celestial Mechanics and Dynamical Astronom