EdX offers many free online courses.

https://www.edx.org/

Astrophysics: Exploring Exoplanets

Explore the mysteries of exoplanets - planets around other stars – in this introductory astrophysics course.

Super-Earths and Life

Learn about the Earth, life, and how we can search for life elsewhere in the universe.

https://www.youtube.com/watch?v=1DHJp44qvwE&feature=youtu.be