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“Planet
formation and evolution:
key processes to understand the
diversity of planetary systems”
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Date: |
Download-files: |
Time: |
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Thursday,
19. April 2018 |
Video-Recording for any system with MP4-support
- Video.mp4 (ca.470 Mb) |
15:15 – 16:25 |
Alessandro Morbidelli
(Observatoire de la Cote d'Azur)
Abstract :
The discovery of
a large number of extrasolar planets has demonstrated
that our own
system is not "typical". Exo-planetary systems can be
very different
from our own, and diverse from each other.
Understanding
this diversity is a major goal of modern planetary
science.
The formation of
planetary systems is not fully understood, but major
advances have
been obtained in the last 10 years. New concepts have
been proposed,
such as the streaming instability for the formation of
planetesimals and
pebble accretion for the formation of protoplanets.
It is also now
clear that planets forming in the proto-planetary disks
have to migrate
during their accretion, if their mass exceeds a few
times the mass of
Mars. Accretion and dynamical evolution are
therefore very
coupled processes. This leads to complex evolutions,
very sensitive to
initial conditions and fortuitous events, that are
the key to
understand the observed diversity of planetary systems. The
early formation
of Jupiter and its limited migration due to the
formation of
Saturn are two fundamental ingredients that determined
the basic
structure of the Solar System. The lack of early formation
of giant planets
typically leads to the formation of super-Earth
planets on short
period orbits. There is also evidence that the vast
majority of
planetary systems become unstable after the removal of the
protoplanetary
disk. The effects of this instability are very
different
depending on the masses of the planets involved. Our Solar
System also
experienced a global instability, but fortuitously our
giant planets did
not develop large orbital eccentricities.