by
Michel Mayor(Observatoire Astronomique
de l'Université de Genève)
→
Europe/Stockholm
FA 31
FA 31
Description
In the last thirteen years, about 300 exoplanets have been
detected. These discoveries have revealed the impressive diversity
of exoplanet orbital properties.
The past thirteen years have also witnessed a remarkable improvement of
the precision of radial velocity measurements with a gain of about a
factor 100.Thanks to the HARPS spectrograph installed in 2003 at
la Silla Observatory ,numerous planets with masses as small as a few
earth-masses have been detected. Several statistical properties are
already emerging and help constraining the formation mechanisms of
these systems.
Is it possible to expect further significant progresses of
Doppler measurements ? Such a possibility could be
of interest to permit radial velocity follow-up measurements
of planetary transit candidates expected from the COROT and KEPLER
space missions : the goal being to get a precise determination
of mass-radius relations from terrestrial planets to brown dwarfs.
Recently , we have been able to get a first insight in the
internal composition of a Neptune analogue from ground based
observations.
A radial velocity precision at the level of 0.1 m/s does not seem
out of reach. With an observing strategy adapted to minimize the
influence of the stellar intrinsic variability (magnetic activity,
acoustic modes) we should be in position to explore statistical
properties of terrestrial planetary systems.
