It was a hot, humid day, and my brother Walt and I had decided that the only way to survive it would be to go swimming in a deep swimming hole across Mr. Blickez's pasture(牧场) and through some woods.

    The only problem with our plan was that this pasture was guarded by a huge, mean Hereford bull. Mr. Blickez had told us that Elsie was them eanest bull in the township, maybe even the county, and we believed him. But the hotter it got, the more we thought there was something doubtful about his claim. For one thing, we remembered Mr. Blickez liked telling tall tales; for another, Elsie seemed like an odd name for a bull.

    Finally, I talked Mom into asking permission for us to walk through the pasture, but then another problem surfaced. Mom said she would talk to Mr. Blickez if we would take our cousin Joanie along with us. Joanie was almost two years older than me and a head taller. If her teasing ever got around my grade school, it would be all over for me. In fact, I still had a headache from a quarrel with her that morning. “I'm not going swimming with that dumb girl cousin.” I told my mom.

  “Either Joanie goes with, or you stay home alone,” Mom said inher serious tone. I gave in and we set out. On our way across the pasture, Walt yelled suddenly. Elsie had approached him quietly and was licking(舔) his back. Joanie and I dove under the wire fence, but while I was on the ground I looked up and saw that Elsie wasn't a big mean bull after all. She was going to keep licking my brother's back as long as he stood still.

    We had many good days growing up and visiting our secret swimming hole guarded by the so-called “big mean bull”. And as it turned out, fora girl cousin, Joanie hasn't been too bad. She's been one of my best friendsover the years.

    A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    “It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components.“The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers' fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.

    Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

    The universe looks like a pretty quiet place to live. But the universe is filled with dangerous things, all struggling to be the one to wipe us off the planet. Happily for us, they're all pretty unlikely, but if you wait long enough, one of them is certain to get us. But which one?

1). Death by Asteroid (小行星)

    Of all the ways we might meet our untimely death, getting wiped out by an asteroid is the most likely. Why? Because we sit in a universal shooting gallery, with 100 tons of material hitting us every day. The problem, though, occurs every few centuries when something big this way comes. If you could ask a dinosaur, I'd imagine they would tell you to take this seriously.

2). Death by Exploding Star

    When a huge star ends its life, it does so with a bang, which sends death spreading across space in the form of high-energy radiation. Many studies show that the bang would have to be closer than about 75 light years to do us any harm. The good news: no stars so close are able to do the deed.

3). Death by Dying Sun

    The sun is important to us; without it, we'd freeze. But the sun is also middle-aged, already halfway to running out of fuel, expanding into a red giant, and cooking us to a fine crisp. Even long before then, it'll warm up enough to raise our average temperature and cause a runaway greenhouse effect, boiling our oceans. Happily, that's a long time from now.

4). Death by Black Hole

    Black holes are misunderstood. They don't wander the galaxy looking for tasty snacks in the form of planets and stars; they turn around the Milky Way just like the hundreds of billions of other stars do. But it's possible that one could wander too close to us. If it did, planetary paths would be disturbed, causing the Earth to drop into the sun or be thrown out into deep space.

    Given that it could be trillions of years or more before even that happens, we don't have to worry too much about black holes.

    My advice? Go outside, look up, enjoy the sun, the moon, and the stars. They may be there forever as far as any one of us is concerned...and forever is a long, long time.

    In many countries, schools have long summer holidays, with shorter holidays in between. However, a new report suggests shortening school holidays to stop children forgetting what they have learnt during the long summer break. Instead of three school terms, it says, there should be five eight-week terms. And there should be just four weeks off in the summer, with a two-week break between the other terms.

    Sonia Montero has two children at primary school and works full-time. She supports the idea. “The kids,” she says, “have much longer holidays than me and I can't afford to take several weeks off work, so I need someone to take care of them. But nobody wants the work in the summer months — they all have holidays of their own.”

    Not surprisingly, some young people disagree. Student Jason Panos says “It's a stupid idea. I would hate staying at school in the summer. It's unfair, too. The people who suggest this had long school holidays when they were young, but now they want to stop us enjoying the summer. The kids in Spain and America have much longer holidays than here, but they don't forget everything they've learnt in a few months.”

    Nadia Salib agrees. “Sure,” she says, “the first week at school after the summer is never easy, but you soon get back into it. The real problem round here is that kids get bored after so many weeks out of school, and then some of them start causing trouble. But the answer is to give them something to do, not make everyone stay in school longer.”

    No matter where you live or how you define yourself, these are some of the best activities to get in touch with nature.

Hiking

    One of the easiest and most accessible ways to get close to nature is by setting out on a good old hike. Hiking generally doesn't require any special equipment or special skills; just a good pair of boots, a map, and a thirst for adventure. This activity can be as relaxing as you make it. Suggestion: consider doing a little advance research on Trails.com or EveryTrail.com.

    Backcountry Camping

    Why limit yourself to just a day hike when you can have a full weekend (or longer) adventure? Backcountry camping involves packing your tent, sleeping bag, food，and water on your back to set up camp in a remote location. If you're an experienced hiker and camper, this is an excellent way to test your survival skills and explore the wildness. Many parks require backpackers to obtain permits, so make sure to register and map your route before stepping on the trail.

    Mountain and Road Biking

    Unlike long hikes through the woods, biking allows you to cover more ground and travel farther while still being in nature. Mountain biking typically involves riding up and down steep slopes, between trees, and over rocks. If this sounds too intense or your tires aren't suited for a rocky path, consider taking a road bike or a hybrid on paved trails through forest preserves or along country roads.

    Teen Art Show

    Do you want to see your artwork displayed alongside other teens' artwork? Don't miss your opportunity! Showcase your paintings, sculptures, photographs and other artworks at the Environmental Educational Center. The show will provide an opportunity for artists to network, provide feedback and become a resource for others.

    Activity fee: $25

    Night Fishing

    Escape the night and join us as we fish at Desert Breeze Park. No experience needed. We will provide the fishing poles, transportation, the bait, help you catch a fish and best of all, teens 14 years and under do not require a license to fish.

    Location: Desert Breeze Park

    Activity fee: $22

    Overnight Snow Trip

    Join the City of Chandler in an exciting new trip! We will travel up to Camp Tontozona and enjoy great food and a campfire in the early evening. Snow play will be the highlight as we explore the snow-filled meadows(草地) of Woods Canyon Lake and sled down small hills in the area. You will be responsible for your own ski/snowboard equipment.

    Location: Camp Tontozona

    Activity fee: $30

    Paintballing

    Come out and play paintball with all your friends! Join the City of Chandler as we go to Tempe Indoor Paintball. This is a great way to join in the fun of playing paintball for a low, low cost. All equipment is included. Please wear old clothes because clothes can get dirty easily!

    Location: Tempe Paintball

    Activity fee: $28