A pioneer is one of the first settlers in a new place. If you desperately want to experience life in space, maybe you will be one of the pioneers who live in the first moon settlement.
Pioneer comes from the old French for foot soldier or laborer, and particularly for groups of soldiers that would go out ahead of the rest of the troops to prepare the way. The European settlers who came to America in the 16th century are known as pioneers, as are the later groups who traveled West in the 18th and 19th centuries. We also use pioneer for anyone who takes initiative in a field, such as science or education.