As a matter of fact, the purpose of launching so many detectors to space is to find a planet with life and the basic element – water.
The moon is far away from Earth, but it is the nearest star to Earth. People have been fascinated by the moon since ancient times until 1969 when astronauts from America landed on the moon. They found that the moon was just a satellite, without water, air, atmosphere and life, so people’s fantasies about moon were broken. The moon is a real “Wide-cold Palace”, it also has very bad weather, extremely cold at night and extremely hot during daytime. Nothing can subsist on the moon. When the astronauts landed on the moon, it was as if the distance went from 380 thousand kilometers to zero kilometers. All the beautiful fantasies and legends about moon were broken, so people now aim their eyes on Mars. They hope that one day the astronauts can step on Mars and realize our new dream.
Since we know the truth of moon, it is not so tempting to us. But poems about the moon can still give us some yearning.
Compare the beginnings of space travel with exploring space today. The exploration of space today is more useful. Many people are fond of Mars because among the nine planets in the solar system it is the most similar to Earth, so we call them “Brother Planets”. On Mars, there is a thin atmosphere lay and some oxygen. The detectors have found that there once exisited water. Due to the low gravity, the water all ran into space. The exploration of space is not only helping us know more about the unknown space, but also telling us a way to the new science and possibly a homeland. In other words, people may realize the dream of living on another planets.