Site Map
Follow us on Facebook Follow us on Twitter YouTube channel
Centro de Astrofísica da Universidade do Porto
Exoplanet science with astrometry from ground and space

Johannes Sahlmann
European Space Astronomy Centre, Madrid

Extrasolar planets are commonly found around stars in the Galaxy but many questions concerning their formation and evolution remain open. Further progress relies on obtaining a comprehensive exoplanet census over a wide range of stellar types and planet parameters, which necessitates the combination of complementary observational techniques. Accurate measurements of stellar positions, i.e. astrometry, can inform us on the properties of extrasolar planets that are difficult to obtain with other techniques. However, detecting the orbital reflex motion of the host star with a typical amplitude smaller than 0.1 milli-arcseconds is challenging for present-day instruments. I will present an overview of the observing techniques that can reach the necessary precision, which include large ground-based facilities and dedicated space observatories, and highlight their contributions to the exoplanet field so far. In particular, I will show new results from an ongoing astrometric planet search around very low-mass stars and brown dwarfs with the VLT. Finally, I will discuss the Gaia space astrometry mission and present my view of its impact on exoplanet research.

22 April 2015, 11:00

Centro de Astrofísica
Rua das Estrelas
4150-762 Porto

Institute of Astrophysics and Space Sciences

Institute of Astrophysics and Space Sciences (IA) is a new but long anticipated research infrastructure with a national dimension. It embodies a bold but feasible vision for the development of Astronomy, Astrophysics and Space Sciences in Portugal, taking full advantage and fully realizing the potential created by the national membership of the European Space Agency (ESA) and the European Southern Observatory (ESO). IA resulted from the merging the two most prominent research units in the field in Portugal: the Centre for Astrophysics of the University of Porto (CAUP) and the Center for Astronomy and Astrophysics of the University of Lisbon (CAAUL). It currently hosts more than two-thirds of all active researchers working in Space Sciences in Portugal, and is responsible for an even greater fraction of the national productivity in international ISI journals in the area of Space Sciences. This is the scientific area with the highest relative impact factor (1.65 times above the international average) and the field with the highest average number of citations per article for Portugal.

Proceed on CAUP's website|Go to IA website