Noses are wonderful things. They help us breathe. They are lined with mucous and hairs called cilia, which trap germs and tiny particles that can make us sick.

Noses are wonderful things. They help us breathe. They are lined with mucous and hairs called cilia, which trap germs and tiny particles that can make us sick.

How much of America’s rainfall ends up in the Mississippi River? Which mountain range grew around the Danube River? Are there more kinds of fish in the Amazon

In our galaxy, there are stars and solar systems. There are comets, asteroids and a whole lot of solid material. There is also a lot of space between star syste

Our galaxy contains about 200 billion stars. Astronomers believed that some of these stars must have solar systems with planets. They went looking – and found