Space is where our future is — trips to the Moon, Mars and beyond. Most people would think that aside from comets(彗星) and stars, there is little else out there. But, since our space journey started we have left so much trash(垃圾) there that scientists are now concerned that if we don't clean it up, we may all be in mortal(致命的) danger.

    The first piece of space junk was created in 1964, when the American satellite Vanguard Ⅰ stopped operating and lost its connection with the ground center. However, since it kept orbiting around the Earth without any consequences, scientists became increasingly comfortable abandoning(抛弃) things that no longer served any useful purpose in space.

    It is estimated(估计) that there are now over 500,000 pieces of man-made trash orbiting the Earth at speeds of up to 17,500 miles per hour. The junk varies from tiny pieces of paint chipped off rockets to cameras, huge fuel tanks, and even odd items like the million-dollar tool kit that astronaut Heidemarie Stefanyshyn Piper lost during a spacewalk.

    The major problem with the space trash is that it may hit working satellites and damage traveling spacecraft(飞船). Moreover, pieces of junk may collide(碰撞) with each other and break into pieces which fall back to the Earth. To avoid this, scientists have invented several ways for clearing the sky. Ground stations have been built to monitor larger pieces of space trash to prevent them from crashing into working satellites or space shuttles. Future plans include a cooperative effort among many nations to stop littering in space and to clean up the trash already there.

    The Parthenon(帕特农神庙) in Athens is a building with a long and complex(复杂的) history. Built nearly 2,500 years ago as a temple celebrating the Greek goddess Athena, it was for thousands of years the church of the Virgin Mary of the Athenians, then a mosque (清真寺), and finally a ruin. The building was changed and the sculptures(塑像) much damaged over the centuries. By 1800 only about half of the original sculptural decoration remained.

    Between 1801 and 1805, Lord Elgin, the British ambassador to the Ottoman Empire(奥斯曼帝国), which controlled Athens, acting with the full knowledge and permission of the Ottoman authorities，removed about half of the remaining sculptures from the fallen ruins and from the building itself. Lord Elgin loved Greek history and transported the sculptures back to Britain. The arrival of the sculptures in London had a huge effect on the European public, greatly increasing interest in ancient Greek culture and influencing contemporary artistic trends. These sculptures were gained from Lord Elgin by the British Museum in 1816 and since then they have all been on show to the public, free of charge.

    Since the early 1980s, however, the Greek government has argued for the return of all the Parthenon sculptures in the British Museum. They have also challenged the British Museum Board of Trustees' legal title to the sculptures.

    The British Museum, however, insists that it exists to tell the story of cultural achievement throughout the world, from the dawn of human history over two million years ago until the present day. The museum considers itself an important resource for the world: the breadth and depth of its collection allows the world public to re-examine cultural identities and explore the complex network of interconnected world cultures.

    It also says that, within the context of this unparalleled collection, the Parthenon sculptures are an important representation of ancient Athenian civilization. Each year millions of visitors admire the artistry of the sculptures and gain insights on how ancient Greece influenced — and was influenced by — the other civilizations that it came across.

    Elephants in Uganda are starting to come close to villages near national parks. The big animals are a real danger to people.

    So, the Uganda Wildlife Authority has been giving people new tools to keep the elephants away: vuvuzelas. They are plastic instruments some fans use at sports events.

    The instruments make a loud sound elephants do not like. The animals leave, and no one is harmed. A spokesperson for the Uganda Wildlife Authority says vuvuzelas work because they do not threaten the elephants. That is important because an elephant that feels threatened is more likely to attack. So far, no one has reported an elephant attacking in answer to a vuvuzela.

    Officials and villagers have tried other ways to stop elephants from coming near farms and houses. They have built beehives – houses for flying insects that sting. They have hung ropes covered in spicy oil. They have dug long, deep holes. And they have used guns, called A-K47s.

    An official from the Uganda Wildlife Authority explains that people shoot the gun in the air to scare the elephant. But over time, the elephants have stopped being afraid of the sound of the gun. They only look at the shooter and wave their ears.

    Another official for the Uganda Wildlife Authority, Gessa Simblicious, says one elephant-prevention solution will not work everywhere in Uganda. And one day, elephants may accept the vuvuzela noise, just as they do the sound of the A-K47.

    But right now, vuvuzelas are an effective, non-violent and fun way to deal with a serious problem.

Do's and Don'ts in Whale (鲸) Watching

    The Department of Fisheries and Oceans has developed guidelines for whale watching in Johnstone Strait, where killer whales are found on a daily basis each summer. It is strongly recommended that vessel (船只) operators follow these guidelines for all kinds of whales.

•Approach whales from the side, not from the front or the back.

•Approach no closer than 100 metres, then stop the boat but keep the engine on.

•Keep noise levels down — no horns, whistles or racing of engines.

•Start your boat only after the whales are more than 100 metres from your vessel

•Leave the area slowly, gradually moving faster when you are more than 300 metres from the whales.

•Approach and leave slowly, avoiding sudden changes in speed or direction.

•Avoid disturbing groups of resting whales.

•Keep at low speeds and remain in the same direction if traveling side by side with whales.

•When whales are traveling close to shore, avoid crowding them near the shore or coming between the whales and the shore.

•Limit the time spent with any group of whales to less than 30 minutes at a time when within 100 to 200 metres of whales.

•If there is more than one vessel at the same observation spot, be sure to avoid any boat position that would result in surrounding the whales.

•Work together by communicating with other vessels, and make sure that all operators are aware of the whale watching guidelines.

    People all need friends because nobody wants to be lonely and a friend can help you in good and bad times. You have made friends since childhood, but you still don't know who your true friends are. Here are some signs to tell you if your friend is a true friend:

Always honest

    Honesty is important to keep a relationship alive. A true friend always tells you the truth. It may be hard sometimes but lying can destroy a friendship. It is important that your friend speaks honestly and never makes up stories.

    There are always periods in your life when you have problems or difficulties. A true friend will always have time to listen to your problems and give advice. It may not be able to offer a solution to your problems but the fact that your friend made time to listen is a sign he/she cares for you. Your friend is not a true friend if he/she can never make time for you when you are in trouble. You also need to be reasonable and accept that your friend also has other things to do so he/she can't always listen immediately to your problems.

Always respectful (尊敬的)

    A true friend will always respect your opinion no matter whether he/she agrees or not. Your true friend may disagree but never insists that he/she is correct.

Always understanding

    It is possible that some problems will arise between you and your friend. A true friend will always be forgiving (体谅的) and understanding even if it isn't his/her fault. We are all different people and we all make mistakes. A true friend is always forgiving and understanding because he/she doesn't want to take the risk of losing his/her best friend.

    Researchers found that compared with young people who spent much of their free time in front of TV sets, those who were physically active often had higher self-respect, better grades and were less likely to have risky behavior like taking drugs, smoking, or drinking. The findings, based on a national survey of nearly 12, 000 middle and high school students, were published in a journal（期刊）.

    “Across the board, children who engaged in any kind of activity were better off than kids who watched a lot of TV,” said study co-author(合著者) professor Penny Gordon Larsen of the University of North Carolina.

    Other studies have linked certain content of television programs, such as violence and sex, to children's behavior. But beyond this issue, Gordon Larsen said that kids who spend hours watching TV” miss opportunities” to develop skills, learn teamwork and have other experiences that their more active peers(同辈) benefit(受益) from

    That doesn't mean, however, that kids have to be on the football team. The study found that some activities like skating and skateboard(滑板)——which adults sometimes frown upon——were also related to better self-respect and less risk-taking.

    That skaters were better behaved than TV-watchers might come as a surprise to some adults who consider these teens to be bad, according to Gordon Larsen. Skateboarding is forbidden in many public areas, and some communities(社区) disagree to build skating parks. But if kids who like to skate have nowhere to do it, “ it's a shame,” said Gordon Larsen.

    Not only should parents encourage their kids to engage（参与） in the physical activities they enjoy, she said, but schools and communities should also do more to create opportunities for children to be active.