TED Talks
Ted: Ted Ed: 3 Planets That Shouldn't Exist
Scishow explores several exoplanets whose features suggest that they shouldn't even have been able to form in the first place! [5:06]
NASA
Nasa: Space Place: What Is a Planet?
Explore our solar system's planets- more specifically what planets are made of, and how they are formed.
Other
Space Science Institute: Alien Earths: Planet Quest
New technologies are continually being developed to help us look deeper into space to discover new planets and to search for other intelligent life forms. Learn about some of these initiatives here.