Throughout history there have been many great explorers. Have you, for example, heard of Marco Polo, the famous Italian traveler? He was the first European to travel to China. He arrived in China in the late 13th century.
About 200 years later, Christopher Columbus sailed from Spain by ship. He was looking for a new way to reach India. However, as you probably know, he didn't reach India. He landed in America. Five hundred years after Columbus in the' 1930s a famous explorer named Richard Byrd was one of the first persons to fly over both the North and the South Poles. Today we continue to explore this world and are studying to explore other worlds, too. In the 1930s Russian and American scientists sent many unmanned spacecraft to the moon. These spacecraft sent back very valuable information about the moon. Then on July 16th 1969 the first manned spaceship to the moon left earth. On that day Apollo 11 blasted off with three American astronauts on board. Four days after blast-off, two of these astronauts landed on the moon. They later explored the surface of the moon. About two days after landing on the moon, they started back to the earth. They arrived safely back on earth a few days later. Today we are sending unmanned spacecraft to other planets. In the future, we might walk on Mars or Venus the way we did on the moon. We might even travel to other galaxies. Who knows? One thing we know for sure is that we will continue to explore this world and other worlds, too.