What is everything in the galaxy made from?
Atoms! Everything you can see, as well as everything you can't see, is made of atoms. Trees, the air and even us - all made up of atoms.
Atoms are the building blocks of everything. They are super-small, and can't be seen with the naked eye.
They have a radius of about 0.1 nanometre. If people were the size of an atom, the entire population of the world would fit into a box about 1,000th of a millimetre across.
Atoms can exist on their own or joined to other atoms of the same type to make up an element, or can form bonds with other atoms to form molecules. Because we can't see them, we show atoms as small coloured circles. Atoms of the same element are the same colour and size. Different types of atoms would be shown as different coloured circles.
The image above shows various molecules. The circles represent individual atoms. The blue atoms are all oxygen, so they are all the same colour and size. The pink circles are nitrogen and the green circles are hydrogen.
We can see that some molecules are made from only one type of atom like oxygen and ozone. But some are made of two or more different types of atom like methane or nitrogen dioxide.
Ready for some questions on these little things we call atoms? Great stuff, lets take a look together........