Max Planck Institute for Astronomy - Annual Report 2005

V.6 The Wilhelm and Else Heraeus Physics School
on »Extrasolar Planetary Systems«
From October 17 th through October 21 st , 2005, a Wilhelm
and Else Heraeus Physics School on extrasolar planetary
systems took place at the Physics Center in Bad
Honnef. The event met with lively interest: a total of 64
participants arrived from 13 countries, almost all of them
PhD students. The world-wide interest in this School not
only demonstrates the interest in this exciting field of
research, but also proves the increasing international
significance of such research done in Germany. This
session of the Heraeus Physics School was organized
by Sebastian Wolf and Thomas Henning (both MPIA)
as well as Willy Kley (University of Tübingen) and
Joachim Wambsganss (Astronomisches Recheninstitut
Heidelberg).
The formation and evolution of planetary systems
and their connection with the origin of life are among
the most fascinating questions of modern astrophysics.
Since the discovery of the first extrasolar planets ten
years ago, this field has grown at a whirlwind pace. At
present, more than 200 extrasolar planet candidates are
known, with the smallest one six times as massive as the
Earth. These topics constitute one of the main research
fields at the MPIA.
The newly discovered »worlds« differ dramatically
in part from the planets of our solar system, presumably
because the current detection strategies are biased. There
are so-called »hot Jupiters«, Jovian planets that circle
their central stars on very narrow orbits. Objects revolving
on orbits with remarkably large eccentricities up to
e � 0.9 have also been found. In our solar system, the orbit
of Mercury is the most elongated one at e � 0.2. These
findings show that existing theories on the formation of
planetary systems that have been calibrated to our own
solar system have to be revised. New results in this field
suggest that interaction between the planets themselves
as well as between the planets and the protoplanetary
disk crucially affect the evolving structure of the planetary
systems.
In addition to the detection of extrasolar planets, it
is now also possible to obtain spatially highly resolved
images of protoplanetary disks – the equivalent of the
solar nebula. Modern astronomical observation methods
such as adaptive optics and infrared and millimeter interferometry
today enable us to investigate the physical and
chemical structure of these disks and thus the place of
origin of planetary systems.
The classical method of detection of extrasolar planets
is the radial velocity technique. Meanwhile other
methods have been used successfully, too, such as the
transit method and the micro-gravitational-lens effect.
However, one of the long-term objectives is to spectros-
Fig. V.6.1: A dignified conference venue: The historical building
of the Bad Honnef Physics Center.
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