Circumstellar Debris and Its Impact on Life: A Solution to Fermi's Paradox?
Astrobiology
Friday 23 April 2010
from 15:00
to 16:00 at
122:026
Speaker :
Ricky Nilsson (Stockholm University, Department of Astronomy)
Abstract :
Observations of circumstellar dust originating from
collisions of planetesimal bodies in asteroid- and Kuiper-belt
analogues indicate that many solar type main-sequence stars are
surrounded by a very large cometary population compared to the Sun. In
fact, the the Solar System could belong to a small group (consisting
of only a few percent of Sun-like stars) of gas-giant planet hosting
systems with very low debris content. This means that any terrestrial
planets, in most exoplanetary systems, would be subjected to a much
higher rate of impacting large bodies than Earth, affecting the
evolution of any potential life (in particular more complex or
intelligent life) on these planets. I will present recent results
hinting at this uncommonly life-friendly feature of the Solar System
and discuss possible implications of high impact stress and extinction
events on the Fermi paradox.
