Astrophysics is an area concerning various physical ranging from planetary sized systems, to galactic scale systems and beyond, that intersects various disciplines such as Newtonian dynamics, relativistic physics and particle physics processes.
For our latest developments/activities in this area, please see the listing below at the end of this article.
An exoplanet is a planet outside the Solar System. In the Milky Way galaxy, it is expected that there are many billions of planets (at least one planet, on average, orbiting around each star, resulting in 100–400 billion exoplanets), with many more free-floating planetary-mass bodies orbiting the galaxy directly.
We study the long-term dynamics of known multi-planet systems. This allow us to test the accuracy of the orbital parameters' determinations, as well as to understand how these systems evolved. We also look for the stable zones in the gaps between already-known planets in order to determine where is it possible to locate Earth-like planets.
See here a movie made by the PhD Animation on "Exoplanets Explained", for a review on the main observational methods used to detect exoplanets.