Dust Particles In Microgravity
- Paper number
IAC-07-E2.2.01
- Author
Ms. Liliana Novais, University of Porto, Portugal
- Year
2007
- Abstract
All stars an all planetary systems were formed from dust and gas. The first are born in the Nebulae and the seconds in proto-planetary rings that may surround young stars. The dimensions of the dust particles present in the nebulae are very small with average sizes of the order of the micrometers and even nanometres, only in some regions can be bigger. A question arises at this moment: how do these small particles form bodies like stars and planets? The process that allows the growth of the particles is known has aggregation. This process is the result of the attraction (electrostatic and gravitical, depending on the size of the particles) between all the different particles. The particles inside the nebulae move freely without any preferential directions or velocities and without an object to create a large gravitational field. Occasionally two particles collide, when this happens two things may occur the collisions can be elastic or inelastic. In the first case one situation can occur, the two particles collide and keep moving without lost of energy. On the second case, and the most interesting for our study, two situations can occur, the first situation is that the two particles collide, some energy is released but the two particles keep moving freely; the second is that the two particles collide and the release of energy is such that allow the adherence forces (surface forces generated by the electrostatic force) between the two surfaces allowing the aggregation of the two particles forming a bigger particle. In the proto-planetary nebulae, we have in the centre a star, and the aggregation will only be possible at some distance of the star, but the process is similar to the one above. The dynamics associated with the movement of particles inside the nebulae can also be transported to the dynamics of the planetary rigs that exist around the giant planets. And even the formation of dust on a volcanic eruption. In this paper I will present the results of a program that will simulate these conditions and study both the dynamics and the aggregation of particles in microgravity.
- Abstract document