Graphs

Over the past few hundred years, astronomers have discovered thousands of stars whose brightness goes up and down over time. These are known as variable stars. But what causes this to happen?

Did you know the Earth is travelling around the Sun at nearly 107,000 kilometres per hour?

The Sun is a constant presence in our life on Earth. It gives us the heat and light we need to survive. But it is not a stable place. The Sun is a ball of hot plasma which is constantly changing.

You have likely heard about the Universe expanding. Or that redshift can tell us about the movements of galaxies. Both are difficult ideas to imagine and understand.