Last month I was lucky enough to have a chance to make a trip into space with my friend Li Yanping, an astronomer. We visited the moon in our spaceship!

    Before we left, Li Yanping explained to me that the force of gravity would change three times on our journey and that the first change would be the most powerful. Then we were off. As the rocket rose into the air, we were pushed back into our seats because we were trying to escape the pull of the earth's gravity. It was so hard that we could not say anything to each other. Gradually the weight lessened and I was able to talk to him. "Why is the spaceship not falling back to the earth? On the earth if I fall from a tree I will fall to the ground." I asked. "We are too far from the earth now to feel its pull, " he explained, "so we feel as if there is no gravity at all. When we get closer to the moon, we shall feel its gravity pulling us, but it will not be as strong a pull as the earth's. " I cheered up immediately and floated weightlessly around in our spaceship cabin watching the earth become smaller and the moon larger.

    When we got there, I wanted to explore immediately. "Come on," I said. "If you are right, my mass will be less than on the earth because the moon is smaller and I will be able to move more freely. I might even grow taller if I stay here long enough. I shall certainly weigh less!" I laughed and climbed down the steps from the spaceship. But when I tried to step forward, I found I was carried twice as far as on the earth and fell over. "Oh dear," I cried, "walking does need a bit of practice now that gravity has changed." After a while I got the hang of it and we began to enjoy ourselves.

    Wetlands are ecosystems found in low, flat areas. Often they border ponds, rivers, lakes, and oceans. Wetlands include marshes, swamps, and bogs.

    No trees grow in a marsh, but there are lots of grassy plants. Ducks, turtles, and many different bugs (虫子) live there, too. Florida has the world's biggest freshwater marsh. The Everglades covers 4,000 square miles. The Everglades is not entirely fresh water, however. Near the sea the fresh water and salt water mix. Some plants and animals can live only in this brackish water.

    Saltwater marshes lie along the East Coast and the Gulf of Mexico. During high tide these marshes are under water. During low tide these marshes can be seen. The water rushes out, carrying bits of plants, dead animals, and minerals necessary for sea animals. Many plants and animals depend upon this ever-changing environment.

    Swamps are forested wetlands. Like marshes, they are often found near rivers or lakes and have mineral soil that drain very slowly. Unlike marshes, they have trees and bushes. Swamps have trees that grow with their roots underwater. But the trees will die if their roots stay underwater too long. Animals such as water snakes and frogs live in swamps.

    Bogs have damp, soft soil. So many dead plants have piled up that there is no longer any standing water. This rotting plant matter turns into peat (泥炭). In Ireland and Scotland peat is dried and burned to heat homes. Bog soil is useful for growing wild rice. Lots of insects live there.

    Most people do not find wetlands beautiful. But wetlands are important. Marshes and swamps store water, thus reducing the flooding a heavy rain can cause. About one-third of all of America's endangered plants and animals live in wetlands. Now laws protect some wetlands. More than a dozen wetlands in the US are refuges (保护区) and wildlife preserves.

    As a gesture of friendship，Mayor Yukio Ozaki of Tokyo，Japan gave Washington, D.C a gift of more than 3,000 Japanese cherry trees on March 17,1912.Every spring, the cherry trees in Washington，D.C. take bloom(开花)，beginning one of the country's loveliest celebrations, the National Cherry Blossom Festival (March 17-April 15). Book your trip now to see this vibrant display of pink and white in this city full of history!

    Washington, D.C. Cherry Blossom In-Depth Tour

    Priee: $45/person

    Available: Mar.25-Apr.15

    Duration: 1 Day

    Highlights: Visit Washington， D.C.; experience the peak period of cherry blossom(April 8-12)

    Itinerary: Guests will start to celebrate the National Cherry Blossom Festival and discover the beauty of cherry blossoms. Next,we will begin our sightseeing city tour including Lincoln Memorial, White House, US Capitol, Madame Tussauds Wax Museum, Washington Monument and International Spy Museum. Then visit the next tourist spot, the Jefferson Memorial. It's the best location to view the cherry blossoms. Finally, guests may board a Potomac River cruise to see the city from the water. Then tour ends.

    Price Includes: Ground Transportation

    Admission Fees:

    Note: If you would like to join in the optional activities, please pay the fee in cash to the tour guide. You cannot buy the tickets on your own or use City Pass. The tour guide will arrange the tickets for the group.

    For tourists holding the Barcelona Card, the information below will be useful if you plan to admire some artworks or architectures there.

    Sagrada Familia

    Opening hours: 09:00-18:00(October-March); 09:00-20:00(April-September)

    Admission: 11, or 11, or 10 with the Barcelona Card

    The project's vast sale and its special design have made it one of Barcelona's top tourist attractions for many years.

    La Pedrera

    Opening hours: November-February: 09:00-18:30; March-October: 09:00-20:00

    Admission：$ 9.50. Save 20% with the Barcelona Card.

    It is a unique modernist building made of bricks and colorful tiles（瓦）. Visitors can see the amazing 800 square meters attic（阁楼）with 270 brick arches that give you a feeling that you are walking inside the skeleton of a whale.

    Barcelona FC Museum

    Opening hours: 6th April-4th October:10:00-20:00;the rest of the year. 10:00-18:30

    Admission：$8.50 for entry to the museum and $17 for a guided tour.

    When you buy your ticket you have two options: a ticket for the museum to see the football stadium or a special one for $15 where you get to see the stadium and the scenes at the club.

    Picasso Museum

    Opening hours: Check the website for details as they vary depending on the time of the year.

    Admission：$9 for main exhibition-extra for special showings. Save 50% with Barcelona Card.

    The museum has arranged Picasso's paintings from his early days to his final works. Arranging the paintings in this way gives you a fascinating insight into the development of Picasso.

Dark Sky Parks around the World

    Warrumbungle National Park

    Situated in the central west slopes of New South Wales is Australia's only dark sky park, Warrumbungle. The park has served as a dark sky park since July 2016. Its crystal-clear night skies and high altitude make it a natural, educational, and astronomical heritage site in the southern half of the earth. Tourists can use Australia's largest optical telescope within the park boundaries to view the auroras (极光), the Milky Way, and faint shooting stars.

    Sark

    Sark is a Channel Island near the coast of Normandy under the protection of the UK. It was the World's First Dark Sky Island set up in January 2011. Its historical and cultural blend attracts over 40,000 tourists annually. With no motor vehicles and public lighting on the island, there is an exceptional view of the dark skies. A rich Milky Way is visible in the dark night skies from the shores of the island.

    Pic du Midi de Bigorre

    Pic du Midi de Bigorre in France was designated as a dark sky park in December 2013 making it the second largest dark sky park in the world. The park covers 3. 112 square kilometers spread across the Pyrenees National Park and UNESCO's World Heritage site, Pyrenees-Mont Perdu. The park attracts over one hundred star watchers every year. The Observatory Midi-Pyrenees, which was built in 1870, is one of the world's highest museums at a height of 2,877 meters above sea level.

    Ramon Crater/Makhtesh Ramon

    Ramon Crater is a unique 1,100-square-kilometer nature reserve located in the Negev Desert in Israel. In 2017, the Ramon Crater became the first designated dark sky park in the Middle East. Its location, rough climate, and forbidding landscape that are characteristic of the Negev have largely defeated historical attempts for human settlement, making it a great place to view the night skies. Stargazers usually camp in the desert to have an uninterrupted view of the stars, planets, and the Milky Way.

    Samuel Osmond is a 19­year­old boy student from Cornwall, England. He never studied the piano. However, he can play very difficult musical pieces by musicians such as Chopin and Beethoven just a few minutes after he hears them. He learns a piece of music by listening to it in parts. Then he thinks about the notes in his head. Two years ago, he played his first piece Moonlight Sonata (奏鸣曲) by Beethoven. He surprised everyone around him.

    Amazed that he remembered this long and difficult piece of music and played it perfectly, his teachers say Samuel is unbelievable. They say his ability is very rare, but Samuel doesn't even realize that what he can do is special. Samuel wanted to become a lawyer as it was the wish of his parents, but music teachers told him he should study music instead. Now, he studied law and music.

    Samuel can't understand why everyone is so surprised. "I grew up with music. My mother played the piano and my father played the guitar. About two years ago, I suddenly decided to start playing the piano, without being able to read music and without having any lessons. It comes easily to me—I hear the notes and can bear them in mind—each and every note." says Samuel.

    Recently, Samuel performed a piece during a special event at his college. The piece had more than a thousand notes. The audience was impressed by his amazing performance. He is now learning a piece that is so difficult that many professional pianists can't play it. Samuel says confidently, "It's all about super memory—I guess I have that gift."

    However, Samuel's ability to remember things doesn't stop with music. His family says that even when he was a young boy, Samuel heard someone read a story, and then he could retell the story word for word.

    Samuel is still only a teenager. He doesn't know what he wants to do in the future. For now, he is just happy to play beautiful music and continue his studies.