【推荐1】Scientists have discovered a “monster black hole” so massive that, in theory, it shouldn’t exist. It’s a stellar (恒星) black hole — the type that forms after stars die, collapse, and explode. Researchers had previously believed that the size limit was no more than 20 times the mass of our sun because as these stars die, they lose most of their mass through explosions that expel (排出) matter and gas swept away by stellar winds.

This theory has now been toppled by LB-1, the newly discovered black hole. Located about 15,000 light years away, it has a mass 70 times greater than our sun, according to a press release from the Chinese Academy of Sciences.

The findings were published by Chinese researchers in the journal Nature on Wednesday. “Black holes of such mass should not even exist in our galaxy, according to most of the current models of stellar evolution,” said Liu Jifeng, head of the team that made the discovery.

“LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation.”

Scientists are now scratching their heads at how LB-1 got so huge.

The Chinese team has proposed a number of theories. LB-1’s sheer size suggests that it “was not formed from the collapse of only one star,” the study said — instead, it could potentially be two smaller black holes orbiting each other.

Another possibility is that it formed from “fallback supernova.” This is when a supernova — the last stage of an exploding star — ejects (排出) material during the explosion, which then falls back into the supernova, creating a black hole.

This fallback formation is theoretically possible, but scientists have never been able to prove or observe it. If this is how LB-1 formed, then we may have “direct evidence for this process” for the first time, the study said.

There are several types of black holes and stellar black holes like LB-1 are on the smaller side, according to NASA. Supermassive black holes are much bigger — they can be billions of times the mass of our sun.

Scientists believe supermassive black holes may be connected to the formation of galaxies, as they often exist at the center of the mass star stems but it is still not clear exactly how, or which form first.

【推荐2】On a clear night, the sky is a wonderful thing. Is there life out there somewhere? Is there another place like Earth where life might exist? If so, where is it? And how far away is it?

Recently, the American Kepler spacecraft found “22b”, a planet about six hundred light years away. It is the first planet in a “habitable zone” outside the solar system. That means the planet orbits a star like our Sun, but it is not too close to it, nor too far away. Because of this position, scientists say Kepler-22b might have water, one of the main things needed for life.

The newly-discovered planet is about two and a half times larger than the Earth. It is closer to its star than we are to the Sun, but 22b’s sun is smaller than ours, and doesn’t produce as much heat. Scientific instruments show the new planet could be made of gases, rocks or some kinds of liquids.

The Kepler spacecraft was named in honor of Johannes Kepler, the seventeenth century German astronomer. It was designed to examine a small part of the Milky Way galaxy and search for places like the Earth. It was made to inspect over 150, 000 stars and measure how bright they are. It looks to see if a star’s brightness gets less over a short time.

If a planet passes between Kepler and the star, it blocks out part of the light. That is what suggested to scientists that there is at least one planet orbiting the star. The instruments on Kepler show the new planet as a small, black dot moving across its sun. An important part of the Kepler experiment is on the Earth. After the spacecraft gathers information, scientists use the space telescopes on the ground.

Scientists have found over 2,300 new planets since Kepler was launched. About 200 of these are about the size of the Earth. Most are much larger, but it is the new planet’s distance from its star that is important. For life to possibly exist there, the planet’s temperature must not be too hot or too cold.

【推荐1】One thing you probably always wondered about is why Americans drive on a different side of the road than their British cousins. It might seem strange that U.K. drivers stay on the left, but they are not alone. Around 35 percent of the world population does the same, including people in Ireland, Japan, and some Caribbean islands.

It is said that originally almost everybody traveled on the left side of the road. However their mode of transport was quite different from today: Think four legs instead of four wheels. For Medieval swordsmen (剑客) on horseback, it made sense to keep to the left to have their right arms closer to their opponents. Also, it was easier to get on and off a horse from its left side than its right side.

Things changed in the late 1700s when large wagons pulled by several pairs of horses were used to transport farm products in France and the United States. In the absence of a driver’s seat inside the wagon, the driver sat on the back left horse, with his right arm free to use his whip (鞭子) to keep the horses moving. Since he was sitting on the left, he wanted other wagons to pass on his left, so he kept to the right side of the road.

The British Government refused to give up their left-hand driving ways and made laws to encourage driving on the left. Meanwhile post-revolution France, under their left-handed ruler Napoleon, accepted a permanent move to the right side of the road. During all this driving confusion, the British and the French were giving up their power across the globe, and as part of their rapid colonization (殖民化) they insisted that the countries they took over drive on the same side of the road. This explains why former British colonies (殖民地) such as Australia, New Zealand, and India drive on the left, while former French colonies like Algeria, Ivory Coast, and Senegal drive on the right.

【推荐2】Negative effects of social media on teenagers

In the past few years, we have seen a rapid growth in the use of social media and networking sites like Facebook, Twitter, MySpace, etc.    1    However, it is also important for them to realize some of the negative effects of these sites. Here, we are listing some negative effects that social media may have on teenagers.

They share too much. Everyone of us has our own set of beliefs and ideas.    2    However, sharing such ideas on website like Facebook may lead to this information being passed on to people we don’t know well.

    3    Social media sites may have an emotional impact on teenager who are suffering from low confidence. Such teenagers may judge their success by the number of friends they have on the Facebook or whether they are included in a specific group of people. This may further weaken their confidence.

They affect social skills. Due to spending more time online teens often do not notice the importance and appropriate behaviors related to face-to-face contact.    4    It is a pity these skills may not develop properly online.

They may result in identity theft(身份盗用). One of the big problems with social media sites is that teenagers often do not fully read or understand the privacy setting of their accounts. They do not realize the risks of giving away personal information. According to a recent survey, 20% of the teenagers think it is perfectly safe to post their personal information and photos online.    5    

【推荐3】Nobel prize-winners, legendary authors, and famous scientists - you might think all these people were born to be creative. However, that's not always the case.

While well-known figures like Pablo Picasso and Albert Einstein did their most significant work in their youth, famous American poet Robert Frost and English-born natural scientist Charles Darwin were known as “late bloomers” - people whose talents were not noticeable until later in life.

This idea of “peaking” at different times inspired new research from the United States. “Many people believe that creativity is exclusively (独有地) associated with youth, but it really depends on what kind of creativity you're talking about,” said Bruce Weinburg, a professor of economics at the University of Chicago and co-author of the study.

According to the study, published carlier this month in the journal De Economist, here are two types of people: conceptual (概念的) and experimental thinkers.

To reach his conclusion, researchers took the 31 previous winners of be Nobel Prize in economics and arranged them according to when they did their most significant work, to identify their creative peaks.

Some peaked from ages 25-29. Classified as conceptual thinkers, these people think outside of the box, coming up with new ideas before they become used to the conventional way of doing things.

The second creative peak came with economists in their 50s. These are experimental thinkers who have been in their fields for a long time. This allows them to learn from errors and experiment with different processes, before eventually finding new solutions.

“Whether you hit your creative peak early or late in your career depends on whether you have a conceptual or experimental approach,” said Weinburg. He added that their study isn't limited to economics, saying it can apply to other creative disciplines (知识领域). So if you're struggling to come up with new ideas, don't panic. Your creative peak may be yet to arrive.

【推荐1】Damage to Ozone layer Gets Worse

In the middle of winter, when snow is falling in many parts of the United States, scientists have sounded a warning to people who plan to spend many hours in the sun this summer. The warning is: The sun’s summertime rays are more dangerous than once thought.

A team of scientists from 80 nations recently reported to the United Nations that a layer of ozone (臭氧层) in the atmosphere, which protects humans from harmful levels of ultraviolet（紫外线） radiation, will be thinner over the United States this summer. The thinner layer allows more ultraviolet rays from the sun to reach Earth. The extra amount of ultraviolet radiation could cause an increase in the number of cases of skin cancer.

Scientists first became concerned about the ozone layer in the mid-1980s when a hole was discovered in the layer above Antarctica during the winter. The hole was caused by chemicals used in refrigerators and air conditioners. When these chemicals are sent out into the atmosphere, they produce gases that destroy the ozone.

Concern about the protective ozone layer rose more recently when data from satellites and ground stations showed that ozone levels were dropping over the United States and other populated areas in the world.

Although many countries have already begun stopping the use of ozone destroying chemicals, the new findings are expected to promote the timetable for a total ban of the chemicals.

【推荐3】Many people don’t have a home because of an illness or because they lost their jobs. They have bad health and can’t start working, and because of that, they can’t pay for a doctor, so it’s a never-ending circle. Homeless people don’t have anywhere to go, so they have to sleep on the streets, covering themselves with newspapers and looking through the rubbish cans to find some food or warmer clothes.

Seeing these horrible living conditions, the Australian charity Beddown decided to help these people in need. They came up with an amazing idea to make shelters in places that are vacant at night-like parking lots! The organization asked one of the largest car park-opera tors, Secure Parking, and they agreed upon it.

“It was great to start with a group of our volunteers to help us and set up some beds. Although as expected we had a few challenges to overcome, it was good to start bringing Bed down to life. Beddown will provide an immediate response for those who can not sleep well to access safe, find shelter-and access to a real bed and a great night’s sleep. We will work with our other partners to provide long-term solutions to providing our guests with accommoda-tion, education and employment opportunities.” The founders of Beddown said in one of their Instagram posts.

The charity also provided other services to the guests, like doctors, nurses, dentists, hairdressers. They gave them new clothing, a place to clean themselves and helped provide social services. “After spending the week here, having a good sleep at night, it reminded me of life and I want to begin my life again,” one homeless man said.