Next autumn when you see wild geese heading south for the winter flying in a V formation, you might think about what scientists have discovered as to why they fly that way.

    As each bird flaps its wings, it creates uplift(提升) for the bird immediately following. By flying in a V formation the whole group adds at least 71% greater flying range than if each bird flies on its own.

    People who share a common direction and sense of community can get where they are going more quickly and easily because they are traveling on the push of one another.

    When a wild goose falls out of the formation，it suddenly feels the drag and resistance of trying to go alone and quickly tries to get back into the formation to take advantage of the lifting power of the bird in front. When the head goose gets tired，it flies back into the formation and another goose flies to the front. It is wise to take turns doing difficult jobs whether it is people or wild geese flying south.

    Wild geese honk (发出雁叫声) from behind to inspire those up front to keep up their speed. What can we learn from this?

    When a wild goose gets sick or wounded by gunshots，and falls out of the formation，two other geese will fall out with that goose and follow it down to lend help and protection. They will stay with the fallen goose until it is able to fly or until it dies，and only then will they go on with their own or with another formation to catch up with their group.

    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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    The sky is large place, and though it has been carefully examined for centuries, new features still turn up. Last March it was the rule of Uranus (天王星), and last week astronomers announced what may turn out to be a new planet, though a very small one, in the solar system.

    The object was first sighted last month by Charles Kowal, an astronomer at the Hale Observatories in Pasadena, Calif. Mr. Kowal observed a faint trail of light on photographic plates, indicating that something was moving in relation to the background of stars. Other observers have confirmed the discovery.

    The “mini-planet”, identified for the time being as “Object-Kowal”, appears to be about 1.5 billion miles away, between the orbit of Saturn and Uranus, and its diameter (直径) has been estimated at between 100 and 400 miles. Its orbit has not been determined yet, but if the orbit proves to be roughly circular, like that of the major planets, the new object would probably take 66 to 70 years to make a circuit of the sun.

    Some astronomers have speculated that Mr. Kowal's discovery may be the first indication of an asteroid (小行星) belt beyond Saturn.

    What if we could replace oil with a fuel which produced no pollution and which everybody had equal access to? The good news is that we can, in fact, we are swimming in it -literally.

    Hydrogen is one of the building blocks of the universe. Our own sun is basically, a big，dense cloud of the stuff. And hydrogen can be used to create electricity for power, heat and light.

    The problem is that hydrogen is everywhere and nowhere at the same time. It does not exist as a material on its own, but is always part of something else. So it has to be separated before it can be used.

    Most commercial hydrogen in use now is created from natural gas. As oil will start to run out in around the year 2030. It makes sense to produce as much hydrogen as possi­ble as soon as we can. But natural gas supplies will also begin to run out soon after. Another source is needed.

    Researchers are now using electricity to make water into hydrogen. Companies are working on the problem in their own areas. The first commercial hydrogen "fuel cells" for computers and mobile phones have already come on to the market Auto companies have also invested over US $2 billion in the production of hydrogen fuelled cars.

    The nations of a hydrogen fuelled planet would not fight over energy recourses. There would be a great reduction in pollution, the only by-product of creating hydrogen is pure drinking water something that is very scarce in many parts of the world. But that is not where the good news ends, once the costs of producing hydrogen have been brought down, it will possibly provide power for a third of the Earth's popula­tion that has no electricity.

    And electricity creates wealth. In South Africa over the last decade there has been a large programmer of electrification. Thanks to the programmer, people do not have to spend their days looking firewood to burn for heat and with electric light, they can work long into the night

Some scientists see radical changes in the way the human race co-operates. Hydrogen creates electricity, and is also created by it. With dual use fuel cells, everyone who consumes energy could also produce it. Late at night, a man drives home in London and connects his car into the "worldwide hydrogen web", which it supplies with electricity. A few hours later, a man in Beijing uses that electricity to power the hydrogen cell in his car. Hydrogen could be the first democratic energy source.

    Like all dreams of the future, it seems very far away. But the threat of war and terrorism in the Middle East has made governments and businesses more aware of the need to end oil dependency and spend more time and money on hy­drogen resource. So maybe the threat of war is not a completely bad thing for the future of the human race.

    People have grown taller over the last century, with South Korean women shooting up by more than 20cm on average, and Iranian men gaining 16.5cm. A global study looked at the average height of 18-year-olds in 200 countries 1914 and 2014. The results show that while Swedes were the tallest people in the world in 1914, Dutch men have risen from l2th place to claim top spot with an average height of 182.5cm. Larvian women, meanwhile, rose from 28th place in 1914 to become the tallest in the world a century later, with an average height of 169.8cm. James Bentham, a co-author of the research says the global trend is likely but once you average over whole populations, genetics plays a less key role," he added.

    But while height has increased around the world, the trend in many countries of north and sub-Saharan Africa causes concern, says Elio Riboli of Imperial College. While height increased in Uganda and Niger during the early 20th century, the trend has reversed in recent years, with height decreasing among 18-year-olds.

    "One reason for these decreases in height is the economic situation in the 1980s," said Professor Alexander. The nutritional and health problems that followed the policy of structural adjustment, he says, led to many children and teenagers failing to reach their full potential in terms of height.

    Bentham believes the global trend of increasing height has important implications. "How tall we are now is strongly influenced by the environment we grew up in," he said. "If we give children the best possible start in life now, they will be healthier and more productive for decades to come."

Welcome to Student Voice

    What is it?

    Student Voice aims to promote student engagement and success in Ontario's schools by listening to and learning from students. Student Voice provides you, the students, with a variety of ways to share your ideas with your school, the education community and the ministry about what would help support your engagement in your learning. Student Voice can help you take action to shape your learning environment while you build your skills.

    Check out this video to get an idea of what's changing for Ontario students!

    It all starts with you.

    Speak up! You have a voice and we want to hear what you have to say about your education. Your ideas and actions can make a difference in Ontario's publicly funded education system. We want to help you make your school a place where everyone feels welcome and where you are empowered to speak your mind, get involved and become active citizens and leaders.

    Students told as that you want to:

    ●share your ideas with government on how to strengthen student engagement and make Ontario's publicly funded education system even better.

     ●have a school culture where all students feel and know that they belong.

    ●work as partners with your teachers, and participate in school decisions that will shape your lives and the lives of other students.

    This is your education. Speak up and get involved! Let's all work together to ensure Ontario's publicly funded education system remains among the best in the world.

    Send your comments and ideas to studentvoice@ontario.ca