People have always wanted to fly. In the 1700s and 1800s, humans flew in lighter-than-air ships such as balloons, airships, and gliders. It was not until 1903 in North Carolina that two brothers built and flew the first heavier-than-air craft, the airplane. Of course, aviation has come a long way since then. Today s planes fly at high speeds and great heights. They quickly transport passengers, mail, cargo, and our armed forces around the world. This...

Through space exploration humans have learned a great deal about the planets, stars, and other objects in space. More than five thousand spacecraft have been launched into space to gather information since 1957. Without space travel, NASA may never have developed many of the things we take for granted today, such as cell phone cameras, CAT scans, and ski boots. This useful and interesting resource discusses the many types of manned and unmanned spacecraft,...