Life may have evolved on at least three planets within a newly discovered solar system 39 light years from Earth. Astronomers at the NASA have discovered no less than seven roughly Earth-sized worlds orbiting a dwarf star in the system. Scientists had previously identified a tiny number of "exoplanets", which are believed to have the qualities needed to support life. However, the new system contains an unprecedented(前所未有) number of Earth-sized, probably rocky planets, and is being acknowledged as an "accelerated leap forward" in the search for extraterrestrial (外星球的)life.

    Three of the new planets are said to be particularly promising because there might exist oceans. Thomas Zurbuchen, associate administrator of NASA, told a press conference in Washington: "This gives us a hint that finding a second Earth is not a matter of 'if', but 'when'."

    The planets were discovered using NASA's Spitzer Space Telescope, which was able to track how fast each of the planets crossed the star Trappist-l and completed an orbit. From this the research team calculated how far the planets were from their star, and therefore how likely they are to be habitable.

    NASA's Hubble Space Telescope is already being used to search for atmospheres around the planets. Future telescopes, including the proposed European Extremely Large Telescope and the James Webb Space Telescope, may be powerful enough to discover markers of life, such as oxygen in the atmospheres of exoplanets.

    Astronomers believe there could be as many as 40 billion potentially habitable worlds in our galaxy, the Milky Way. Prof Zurbuchen said that now was a "gold-rush phase" in the search for these exoplanets.

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Grandparents Answer a Call

    As a third generation native of Brownsville, Texas, Mildred Garza never planned to move away. Even when her daughter and son asked her to move to San Antonio to help their children, she politely refused. Only after a year of friendly discussion did Ms Garza finally say yes. That was four years ago. Today all three generations regard the move as a success, giving them a closer relationship than they would have had in separate cities.

    No statistics show the number of grandparents like Garza who are moving closer to the children and grandchildren. Yet there is evidence suggesting that the trend（趋势）is growing. Even President Obama's mother-in-law, Marian Robinson, has agreed to leave Chicago and into the White House to help care for her granddaughters. According to a study grandparents com., 83 percent of the people said Mrs. Robinson's decision will influence the grandparents in the American family. Two-thirds believe more families will follow the example of Obama's family.

    “In the 1960s, we were all a little wild and couldn't get away from home far enough or fast enough to prove we could do it on our own,” says Christine Crosby, publisher of Grand a magazine for grandparents. “We now realize how important family is and how important it is to be near them, especially when you're raising children.”

    Moving is not for everyone. Almost every grandparent wants to be with his or her grandchildren and is willing to make sacrifices, but sometimes it is wiser to say no and visit frequently instead. Having your grandchildren far away is hard, especially knowing your adult child is struggling, but giving up the life you know may be harder.

    Learning to speak English well may be the best thing you can do to improve your life. That's right. If you can communicate in English, you can do the following things:

    Contact (联系) people from all over the world. Talk about your ideas and opinions on Internet discussion groups. Send e-mails to interesting people. Learn about their life and culture.

    Travel more easily. Communicate with people wherever you go—English is spoken in more than 100 countries. Ask directions, have a conversation, or ask for help. Maybe English will save your life some day!

    Push your career forward. If you want a good job in business, technology, or science, get out of that armchair and start learning English now! If you already have a good job, start learning before you lose it! Knowing English will let you do the following things:

    Put “excellent knowledge of English” on your CV (履历). Get your dream job, and earn more money.

    Gain technical knowledge. English is the language of technology, especially high technology like computer science, and medicine. If you're going to read about technology, you'll probably have to do it in English.

    Be a world-class businessman or woman. It's simple. International business is done in English. And all business today is international. So if you want to play, you have to know English—to contact other business people, go to conferences, and read international business newspapers and magazines, ect.

    Become a better scientist. Contact scientists from other countries, go to international conferences, and visit research centers abroad. Learn about new scientific discoveries by reading papers, books, and magazines.

    Use your computer more effectively. Most computer applications are in English, so you will understand them better—and become a better employee.

    Seventy-three-year-old George McNeilon selected his food in Value Mart very carefully. After leaving the cashier, he estimated (估计) that he had saved 80 cents and thought that he had got good value for his money again.

    At the exit, the chilly wind reminded him of his gloves. "Now where are they?" He searched here and there, but nowhere could he find them. He was sure he was wearing them when he entered the store. The worried man made a second search in all his pockets, again including the grocery bag. He was sure they must have been dropped somewhere inside the store.

    George bought the gloves at a 25% discount, for just $30, ten years ago. They were genuine lambskin (小羊皮), soft, warm and durable. Until then, he had worn cheaper man-made material that lasted no more than three years. His impulsive decision to buy the expensive gloves turned out to be a good one, which even promoted his social status on the bus, as passengers stared at him enviously for six months out of the year. He enjoyed being envied.

    Bad luck, George thought, to lose his expensive gloves on New Year's Eve. He reentered the store and followed the same route he had walked before. But several minutes of anxious search turned out to be in vain. "Society has changed. People have changed …" he murmured to himself. "Years ago, if people picked up something lost, they would give it back."

    Back home, George was at a loss. In deep winter, he could not do anything without a pair of gloves. If he bought cheap ones, he would have to replace them very soon. If he bought new leather ones, they would cost forty dollars.

    After the holiday, poor George decided to buy another pair of leather gloves. Before boarding the subway, he stepped into Value Mart again to see if by any chance his gloves had been returned to the lost and found office.

    "What color are they?" the woman in the office asked.

    "Black," he answered.

    She looked into her drawer and drew out a pair of men's leather gloves.

    "Are they?"

    "Yes! Those are mine!"

    Parents who help their children with homework may actually be bringing down their school grades. Other forms of parental involvement, including volunteering at school and observing a child's class, also fail to help, according to the most recent study on the topic.

    The findings challenge a key principle of modern parenting(养育子女) where schools expect them to act as partners in their children's education. Previous generations concentrated on getting children to school on time, fed, dressed and ready to learn.

    Keith Robinson, the author of the study, said, "I really don't know if the public is ready for this but there are some ways parents can be involved in their kids' education that leads to declines in their academic performance. One of the things that were consistently negative was parents' help with homework." Robinson suggested that may be because parents themselves struggle to understand the tasks. "They may either not remember the material their kids are studying now, or in some cases never learn it themselves, but they're still offering advice."

    Robinson assessed parental involvement performance and found one of the most damaging things a parent could do was to punish their children for poor marks. In general, about 20% of parental involvement was positive, about 45% negative and the rest statistically insignificant.

    Common sense suggests it was a good thing for parents to get involved because "children with good academic success do have involved parents", admitted Robinson. But he argued that this did not prove parental involvement was the root cause of that success. "A big surprise was that Asian American parents whose kids are doing so well in school hardly involved. They took a more reasonable approach, conveying to their children how success at school could improve their lives."

    Teenagers who spend hours in front of the television may have a poorer diet as young adults.

    A study, which included nearly 1, 400 high school students, found those who watched TV for five hours or more per day had less healthy diets than peers (同龄人) five years later. Why does this happen? Should the parents take any measures?

    On the one hand, people who spend a lot of time in front of the TV, especially teenagers, may snack more, and that may affect their long-term diet quality.

    On the other hand, TV ads for fast food, sweets and snacks tempt teenagers to eat more of those foods. And TV time might also replace exercise time for some kids.

    Lead researcher Dr. Daheia J. Barr-Anderson, of the University of Minnesota in Minneapolis, told Reuters Health a clear correlation between TV time during high school and diet quality in young adulthood. While the heaviest TV viewers were eating the most junk food, those who'd watched less than two hours per day had the highest intake (吸收) of fruits, vegetables, whole grains and high-calcium food. In her opinion, parents should limit and monitor TV viewing.

    As far as I am concerned, children should watch no more than two hours of television per day. And parents should set a good example by eating right, being physically active and curbing their own TV time.