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E. Grün (MPI-K, Heidelberg and HIGP, U. Hawaii, Honolulu)
Dust particles, like photons, are born at remote sites in space and time, and carry from there information that may not be accessible to direct investigation.
In stellar winds of evolved stars, new dust is formed and is injected into interstellar space. Young stardust is mixed with old heavily-processed diffuse interstellar dust, and is subject to passing supernova shocks and ultraviolet radiation. Dusty clouds emerge. The protostar environment is a fertile ground for solids on all size scales, from dust grains to planets, to form. Star formation in cool molecular clouds becomes both a sink of old dust and a source of new dust. Dust in a planetary system is the most processed of the different populations of cosmic dust. Interplanetary dust is permanently replenished by dust ejected from cometary nuclei, the most pristine bodies in the inner planetary system, and released from collisions in the asteroid and Kuiper belts. In our solar system, interplanetary dust exists alongside interstellar dust, which is flowing through the solar system, offering a physical link between our planetary system and the stars.
The dynamics of dust particles is affected by gravitational and magnetic fields. Dust trajectories trace out their radiation, gas, plasma, and dust environments. By accurate dust trajectory measurements we can derive their place of origin: comets, asteroids, or even interstellar space. From the particles' bulk properties and their chemical composition we are able to infer properties of the environments out of which the particles were formed and in which they were subsequently altered. The combination of trajectory determination and chemical analyses on the same dust particle, is called dust astronomy. Recent developments of in-situ dust detectors allow us to combine sensors of these capabilities into a single dust telescope that is carried by a dust observatory satellite in space.
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Bulletin of the American Astronomical Society, 34, #3< br> © 2002. The American Astronomical Soceity.