Even though we knew moon well now, it has many touching legends n ancient times. Chang’e is a beauty who ate the elixir and then flew to the moon, she lived in the “Wide-Cold Palace” (Moon Palce) with a jade rabbit. Wugang always cut down the sweet-scented osmanthus trees on moon as a punishment. Though these legends are not true, we can still store them in our memories.

　　Why do we care so much about other planets? The reason is that the Earth is suffering many troubles. These troubles include: global warming, air pollution, water pollution, the population is quickly increasing, soil deterioration and decreasing natural resoures. The environment is not as good as it once was. All the troubles mentioned above are warnings us that we should pay more attention to the environment, and take care of our mother-Earth. Don’t make it suffer any more troubles. The reason is simple, we have only one Earth. Why not cherish it and make it more beautiful.

　　Even Mars is the most similar to the Earth in the solar system, scientists have said that outer-space is not fit for human beings to live in at the moment. Because there is not enough of the necessary thing that we need in space. We can’t find the basic thing-water. On other planets, so we should assume the attitude, “looking for a horse while riding a donkey, but not looking for a horse while discarding a donkey.” Only remember that we have one Earth. It is our duty to protect and cherish it.

　　In 1990, NASA launched a telescope called “Hubble” to the orbit of Earth. Without the affect of atmosphere, we can see the stars far away about 200 hundred million light-years. It is the farthest area we can see so far in the universe. People learnt a