Scale of the universe
Things in our universe can be unimaginably large and small. In this topic, we'll try to imagine the unimaginable!
Stars, black holes and galaxies
Our universe is defined by stars. This topic explores how they came to be and where they end up. This includes a discussion of black holes and galaxies.
Earth geological and climatic history
What is the Earth made up of and how do we know? What causes the seasons? Are there longer-ranging cycles in Earth's climate?
Life on earth and in the universe
When and how did life emerge on Earth? How did humanity develop a civilization? Is there other intelligent life out there?