A large fraction of exoplanetary systems contain planets that
orbit very close to their host stars. With orbital periods in the
range of days to weeks, tidal forces become important and lead to
significant orbital and physical effects on the planets...
Supernovae, tidal disruption events and merging neutron stars
can provide a wealth of physical insights from nuclear physics to
cosmology; they can teach us about the creation of the elements,
the formation of compact objects, accretion processes...