“Hello, Earth! Can you hear me?” That's voice more than 400,000 people received recently. It was from Philae, a space vehicle that landed on a comet(彗星)in 2014. However, its transmissions (传输信号)back home went silent since then.

It took a long time for Philae to make its way across the solar system (太阳系)and reach comet 67P/C-G. The pace vehicle got there aboard the Rosetta probe (探测器), which has been circling around the comet since Philae separated from it in November, 2014．

Philae's job was to collect materials to study the comet's composition. And for about two and a half days after landing, it did just that, sending the information back to scientists on Earth. But Philae's landing on the comet's icy surface had not been smooth. While touching down, it jumped up and ended up in the shadow of something like a huge rock. Philae runs on solar power, but there was no light in the place where it landed. In the end, it failed to work.

However，as comet 67P/C-G moved closer to the sun, more sunlight reached the space vehicle, allowing it to power up and come back online. Philae then sent something to Rosetta, which passed on the information back to Earth.

“We only received the information for about 85 seconds, but that's enough to let us know it is alive and well,”says Stephan Ulamec, who works for the European Space Agency.“We hope to work out where it landed exactly on the 4-kilometer-wide comet. Now we plan to change how Rosetta moves so that Philae can keep on communicating and receiving instructions.”

    China is a land of bicycles.At least it was back in 1992 when I traveled the country.Back then everyone seemed to be riding a bicycle.Cars were fare.Yet since my arrival in Beijing last year,I've found there are millions of cars. However,bicycles are still popular nowadays.People still use their bicycles to get around.For many,it's the most convenient and cheapest way to travel today.

    It's rush quickly through crossroads,move skillfully through traffic,and ride even on sidewalks（人行道）. Bicycles allow people the freedom to move about,which cars just can't provide.Eager to be part of this aspect of Chinese culture,I decided to buy a bicycle.Immediately I got my new bike I jumped up on the seat and started home.

    My first ride home was orderly（守秩序的）.To be safe, I stayed with a "pack" of bikers while cars on the streets came running swiftly out of nowhere at times.I didn't want to get hit.So I took the ride carefully.Crossing the streets was the biggest problem.It was a lot like crossing a major highway back in the United States.The streets here were wide,so crossing took time,skill and a little bit of luck.

    I finally made it home.The feeling on the bicycle was amazing.The air hitting my face and going through my hair was wonderful.I was sitting on top of the world as I passed by places and people.Biking made me feel alive.

    Charlie studied in a famous college for four years. He studied hard and did well in all his subjects. He hoped to become a good teacher. This year he left the college and began to work in a middle school. He likes his students and is strict with them. He does his best to make his classes lively and interesting.

    One day he carefully explained a chemical reaction to the students of Grade 2 in the chemistry lab.

    “Be careful, everyone,” he said loudly. “Before I make the experiment, there're twenty five atoms of carbon (碳原子), but after I finish it, there're twenty four atoms of carbon left!”

He stopped to watch the classroom and hoped his students would go on explaining it. But the young men looked at each other and nobody answered him. He had to ask,

    “What happens? What makes the atom lost?”

    The classroom was very quiet and none of the students looked at their teacher.

    “Who can tell us where it has gone?”

    Suddenly a soft voice came from the back row, “We did not see anybody leave the lab!”

    Kids are natural scientists. That may be why they ask so many questions.

    Younger kids take up science and math with amazing enthusiasm, yet as they get older they often lose their excitement. Children look on scientific exploration as play, but as they get older they start to connect it with big heavy books, long worksheets and a lot of really confusing words.

    What a tragedy! We had their attention, they were listening, they were participating, they were learning and then we lost it to boredom.

    We need our kids to play more. More play brings up basic scientific concepts(概念). Being familiar with basic scientific concepts brings about exploration which leads to research. Once they are researching, they are completely into the learning.

    My boys built a small 9­hole golf course next to our driveway one day. It was a great product of science. They dug out the holes and channels to guide the golf ball. They played with architecture(建筑学)with a series of pipes they had found in the garage. They tested speed and momentum(动量)by creating one of the holes across the driveway. They experienced biology when deciding which front yard plants could be used as a part of the course and which needed to be pulled up.

    If I had sent them out to the yard to build a 9­hole golf course, it would have never happened. It was because it was their idea that it worked. I try to tell them some of the concepts after the fact. When they ask about something, I try to relate it back to something they have built, experienced, or felt. I try to give them a vocabulary around what they already know.

    An afternoon can change the way kids look at the world. Not bad for a day of play.

    BELJLNG—Eating at a Beijing restaurant is usually an adventure for foreigners, and particularly when they get the chance to order "chicken without sex life" or "red burned lion head".

    Sometimes excited but mostly confused, embarrassed or even terrified, many foreigners have long complained about mistranslations of Chinese dishes. And their complaints are often valid, but such an experience at Beijing's restaurants will apparently soon be history.

    Foreign visitors will no longer, hopefully, be confused by oddly worded restaurant menus in the capital if the government's plan to correctly translate 3, 000 Chinese dishes is a success and the translations are generally adopted.

    The municipal (市政) office of foreign affairs has published a book to recommend English translations of Chinese dishes, which aims to help restaurants avoid bizarre translations. "It provides the names of main dishes of famous Chinese cuisines in plain English," an official with the city's Foreign Affairs office said, "Restaurants are encouraged to use the proposed translations, but it will not be compulsory." It's the city's latest effort to bridge the culture gap for foreign travelers in China.

    "The book is a blessing to tourist guides like me. Having it, I don't have to rack my brains trying to explain Chinese dishes to foreign travelers," said Zheng Xiaodong, a 31-year-old employee with a Beijing-based travel agency.

    "I will buy the book as I major in English literature and I'd like to introduce Chinese cuisine culture to more foreign friends," said Han Yang, a postgraduate student at the University of International Business and Economics.

    It is not clear if the book will be introduced to other parts of China. But on Tuesday, this was the most discussed topic on weibo.com, China's most popular micro-blogging site.

A new study says that more than half the world's ocean area is "becoming greener," and the trend is connected to human-caused global warming.

It's not clear what is driving the greening. In some places, it could indicate changes in the amount of plankton or other organic material floating in the water. Plankton are a cornerstone of the ocean food chain, and these kinds of shifts could have ripple effects throughout the entire marine ecosystem.

The study, published on Wednesday in the journal Nature, examines 20 years of satellite data measuring light reflected at the surface of the water all across the globe, subtle changes that aren't necessarily visible to the naked eye. The research finds that 56 percent of the world's oceans are shifting in color — and on the whole, they're growing greener. The trend is especially strong in the lower latitudes, including the subtropics and tropics.

The researchers then used a computer model to find out whether climate change was playing a part. They conducted one set of simulations representing the oceans under a strong climate change scenario, and then compared them with a second set of simulations imagining a world in which climate change didn't exist. The model suggests that rising global temperatures are to blame.

The exact reasons still require some scientific digging. While climate change seems to be the culprit, the study also indicates that rising ocean temperatures in and of themselves aren't driving the greening.

There are plenty of other ways global warming is affecting the world's oceans, by changing the structure and flow of certain currents, for instance. These kinds of changes can affect the growth of phytoplankton and other factors that might be contributing to the greening.

The findings weren't a surprise to the researchers. They're consistent with the way researchers expect the global oceans to change as the world keeps on warming.

"I've been running simulations that have been telling me for years that these changes in ocean color are going to happen," study co-author Stephanie Dutkiewicz, a senior research scientist at the Massachusetts Institute of Technology, said in a statement. "To actually see it happening for real is no unexpected, but frightening."