The Open University have produced a brand new free course exploring our Galaxy’s population of planets, and some of their many great surprises.

Introduction to explanets »

From the website:

What are the planets outside our Solar System like? Could there be life on them?

Learn about this fascinating area of twenty-first century science in this exciting free course, An introduction to exoplanets.

The course introduces our Galaxy’s population of planets, and some of their many surprises. It explains the methods used by astronomers to study exoplanets, and provides a general introduction to the methods of scientific inquiry. The course culminates in discussion of life elsewhere in our Galaxy.