For centuries, humans have gazed at the stars, dreaming of ways to visit the distant worlds that they seem to contain. In the early 20th century, those dreams began to become a reality, as pioneers like Robert Goddard and Werner von Braun developed the technology that would eventually take us to the moon. Today, space exploration is an international undertaking, with countries like the United States, Russia, and China all operating their own space programs. And while there are still many mysteries to be solved in our solar system, we now have the ability to send spacecraft and even humans to other planets. Who knows what we’ll discover next?