With the detection of exo-planets, planet and star formation has emerged as an exciting, competitive, and quickly evolving field at the forefront of current astrophysical research. Since the planet formation is closely related to the star formation process via an accretion disk feeding the young stellar object, research focuses on the circumstellar disks, their formation and evolution, and the formation of larger bodies inside the disk as building blocks for planets.
A key role both in the star formation process and the formation of planets is played by the small dust particles mixed in the gas of the molecular cloud core where the star is forming. They are important tracers of the dense regions where the star formation starts, contribute to the charging, chemistry, and cooling of the gas, and they are the seed for the planets to be formed in the accretion disk of the young star. Many details of this formation process are still undetectable : we just begin to observe forming planets in disks, but not their building blocks, and the formation of larges bodies from meter size bodies is still not understood.
A team including IPAG members and the project leader just have published papers in the journals Science and Astronomy and Astrophysics about a newly detected phenomenon called "coreshine" which is mid-infrared light scattered by big dust grains in the inner parts of molecular clouds. It indicates that dust grains as building blocks for later formed planets can already grow in molecular cloud cores even before the star formation process has started. The project SEED will focus on the exploration of the dust growth process outside the circumstellar accretion disk surrounding and feeding the young stellar object in the formation process, continously providing a seed population of grown grains for further processing within the accretion disk.
Jürgen Steinacker has received his dissertation at the Max-Planck-Institut für Radioastronie in Bonn, Germany about particle acceleration in solar flares. As Lynen fellow of the Alexander-von-Humboldt foundation, he worked at the Laboratory for High Energy Astrophysics of the NASA Goddard Space Flight Center in Maryland for two years. Returning to Germany, he joined a Max-Planck group about "Dust in star formation regions" at Jena University, received his habilitation on radiative transfer, and is member of the Max-Planck-Institut für Astronomie, Heidelberg, since 2003. He was invited guest professor at the Observatories in Bordeaux and Paris in 2005, 2007, and 2009. Since February 2012, he works as a Chair d’Excellence at IPAG.
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