Abstract

Theories of the Solar System formation have significantly advanced since Kant and

Laplace formulated their nebular hypothesis in the 18 th century. In the current view, our

protosun and the surrounding protosolar nebula formed from the collapse of a cloud of gas

and small dust grains. Within the nebula, small dust grains grow through collisions into larger

bodies that eventually form the planets. Observations show that such protoplanetary nebulae

are ubiquitous in locations where new stars are born. They also show that at least 10% of

nearby Solar-like stars harbor planetary systems very different from our own. These systems

cannot be explained within the standard model and thus revive the discussion of planet

formation. I will discuss how models of protoplanetary nebulae are used in the interpretation of current observations with the ultimate goal to constrain physical and chemical conditions during the planet forming phase.