Investigation

Galaxies are vast collections containing billions of stars, planets, and massive clouds of gas, dust, and ice. Understanding galaxies is a key part of astronomy. One important tool for studying them is classification—grouping them into a few different categories. 

Impact craters are made when a space rock (called a meteorite or asteroid) hits a rocky planet or moon. The impact makes a round hole in the surface, called a crater.

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 probably seen the Moon in the sky, but have you ever studied it in detail?

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.