We can't explore space in the same way we can our own world. If we want to explore a certain part of our own world, we go ourselves. But we can't travel in space, at least, not very far. So how do we explore the stars? One of the earliest tools for studying the stars was the astrolabe. It works in in much the same way as a protractor in geometry, measuring angles. It was used to calculate the difference between the stars and planets.

Nowadays, we have more advanced tools. These instruments measure the waves of radiation given off by objects in space. There is a spectrum to measure how much various objects give off. At the right end of the spectrum, we have gamma rays, X-rays, and other rays. At the other end are radio and infrared rays. We can see only a very tiny amount of these rays, the ultraviolet rays, which make up the rainbow.

Radio telescopes pick up radio waves. The telescopes pick up waves, then amplify them and send them to a computer, which processes the information. By studying these waves, scientists can learn about far away galaxies and planets that are far, far away.

Infrared telescopes pick up on the waves that we feel as heat. We can't see the signals, but can sense them instantly. These allow astronomers to guess at the temperature of a certain object. Some snake have eyes that locate prey by detecting sources of heat.

Ultraviolet telescopes need to be placed outside of Earth's atmosphere in order to work, since our atmosphere blocks out most ultraviolet rays. They pick up on the ultraviolet rays. New stars and many of the most active objects in the universe emit these rays.

We have many inventions with which to explore the solar system. And, in time, who knows? Maybe we will be able to look for ourselves.