Six volunteers are about to find out what it would be like to live on Mars without ever leaving the Earth. Three men and three women will spend eight months living in a special place on the side of a volcano in Hawaii. They are part of an experiment that is designed to mimic（模仿）life on Mars. Their mission began on October 15, 2014. NASA says it could send astronauts to Mars as early as the 2030s. The mission would take more than two years, so NASA needs to know how people would react to living in a small group, isolated from the rest of the world, for such a long time. Some people may become depressed or bored living under those conditions. By studying people living in similar conditions here on Eares NASA hopes to learn how to choose the most suitable people for a space mission, and how to help them get along.

    They will live in a two-story building. The ground floor is about 86 square meters, roughly the size of a small two-bedroom apartment. It includes shared areas like kitchen, dining room, bathroom, laboratory and an exercise room. The upstairs is less than half the size of the downstairs. It contains another bathroom and six small bedrooms. The building is located in an abandoned quarry（采石场）about 2,400 meters up the side of Mauna Loa, the second biggest volcano in the world. It is constantly monitored for signs of volcanic activity. NASA chose the location because the appearance looks very similar to Mars.

    To make it more like being on Mars in the future, they are only able to communicate by email during the experiment. Meanwhile, there will be a 20-minute delay between the time when a message is sent and that when it is received. When they go outside, they will have to suit up in full spacesuits, just as if they were on Mars.

    The commander is Martha Lenio, a 34-year-old Canadian. During the mission, she will run experiments on growing food. The other members have backgrounds in physics and so on. None of them are astronauts.

    Could a cave be the place of buried treasure in a small village in Marajgushu, near Navasha, Kenya? A rumor of treasure has some villagers dreaming of wealth, while ohters see it as a cheat. It's said that in the 1800s a white man left treasure inside the caves.

    This system of caves has become the center of excitement in the village. It is unclear where the rumor came from, but some local people believe white settlers hid gold and other precious metals in the cave before leavign the area, many years ago.

    Local villager Edward Maina says the rumors have brought a lot of treasure hunters flooding into town to dig in the caves. Villages say original treasure seekers entered the cave nearly two months ago before being arrested by police. Local governmetns closed up the entrance, but they broke back in.

    While neither gold nor silver has been found yet, the cave does guard another important resource: water. Many depend on a natural spring coming from the cave and local officials, among them Ward Councilor Gaka Mwaniki, worry the digging could affect or dirty the supply.

    “There's nothing. We've seen ourselves there's nothing in those caves. The cave is natural. It's the water table that they're affecting” says Mwaniki.

    Local resident James Mbugua Njenga wants the situation brought under control. “If at all there's treasure inside there, let the government come and dig and protect the water table,”says Njenga.

    It might be true. It might be a cheat. Whatever the case, treasure hunters continue to be attracted to the mystery of the caves.

    The sharing economy, represented by companies like Airbnb or Uber, is the latest fashion craze. But many supporters have overlooked the reality that this new business model is largely based on escaping regulations and breaking the law.

    Airbnb is an Internet-based service that allows people to rent out spare rooms to strangers for short stays. Uber is an Internet taxi service that allows thousands of people to answer ride requests with their own cars. There are hundreds of other such services.

    The good thing about the sharing economy is that it promotes the use of underused resources. Millions of people have houses or apartments with empty rooms, and Airbnb allows them to profit from these rooms while allowing guests a place to stay at prices that are often far less than those charged by hotels. Uber offers prices that are competitive with standard taxi prices and their drivers are often much quicker and more trustworthy.

    But the downside of the sharing economy has gotten much less attention. Most cities and states both tax and regulate hotels, and the tourists who stay in hotels are usually an important source of tax income. But many of Airbnb's customers are not paying the taxes required under the law.

    Airbnb can also raise issues of safety for its customers and trouble for hosts' neighbors. Hotels are regularly inspected to ensure that they are not fire traps and that they don't form other risks for visitors. Airbnb hosts face no such inspections.

    Since Airbnb is allowing people to escape taxes and regulations, the company is simply promoting thefts. Others in the economy will lose by bearing an additional tax burden or being forced to live next to an apartment unit with a never-ending series of noisy visitors.

    The same story may apply with Uber. Uber is currently in disputes over whether its cars meet the safety and insurance requirements imposed on standard taxis. Also, if Uber and related services flood the market, they could harm all taxi drivers' ability to earn a minimum wage.

    This downside of the sharing needs to be taken seriously, but that doesn't mean the current tax and regulatory structure is perfect.

    As more and more schools rush to put digital devices（数码设备）in the hands of every student, many parents are becoming increasingly concerned about the quality of their children's education. The promise of increased student academic（学业上的）achievement through the use of technology hasn't produced any significant results in the past 20 years.

    Researchers at the University of California Los Angeles conducted a study in 2014 to determine if the social skills of elementary students were blocked by screen time. Two groups of sixth grade students were compared. One group was sent to an outdoor camp for one week with no screen time, while the control group live life as normal. After one week, the students at camp had made significant improvements over their peers（同龄人）. The good news is that when we limit access to screen time and give children the opportunity to interact face to face, they quickly become better at reading the emotional state of others. The bad news is that we have a generation of children that struggle with this basic emotional intelligence skill.

    Too much screen time has been linked to childhood obesity, sleep disorders, behavior problems, and academic challenges. But is there a difference between schoolwork and entertainment media?

    When students are using technology for academic work they are more likely to be communicating with peers, working cooperatively, and developing other important skills. However, all these are impossible when students watch entertainment media. They just sit and watch!

    Parents have right to be concerned about their children's screen time at school, but they should begin by discussing the use of digital media at home. Some parents are continuously engaged in their own devices, responding to every ring of their phones, receiving and sending messages. How can they expect their children to do better?

    Annette Larkins is an incredible woman who looks like a healthy 40-year-old, although she just turned 70. She follows a special raw diet and only drinks rainwater.

    She looks so young that people mistake her to be the daughter, when she's out with her husband of 54 years, but I suppose he isn't complaining.

    Mrs. Larkins says the secret to her beauty lies in her special diet, consisting of organic vegetables, fruits, seeds and nuts grown in her own garden; she calls it the "fountain of youth". The woman doesn't touch anything that has been cooked.

    And another strange thing she does is to collect rainwater, to keep her garden blossoming, but also to drink. But the residents of Miami-Dade County, Florida, didn't always have such a healthy lifestyle. In fact, she consumed meat regularly, as her husband used to own a meat factory way back in the 1960s. It was then that she decided to change her eating habits forever. And what a great decision that was. I mean, just look at her!

    When she started off, Mrs. Larkins was just looking for a few health benefits and never anticipated that she would look like a 40-year-old at the age of 70. Over the 27 years that she has been eating raw, Mrs. Larkins has written two booklets railed Journey to Health and also produced a DVD containing all her healthy secrets.

    Her husband, Mr. Larkins, wishes he had followed her example, because now he looks much, much older and also suffers from diabetes (糖尿病) and high blood pressure. He takes prescription medicine every day, but Annette doesn't even take an aspirin.

London Underground

    The world's first subway was built in London in 1863. At the time, the government was looking for a way to reduce traffic problems in the city of London. The poor areas of the city were so crowded with people that it was almost impossible for horse carriages to get through. The city officials were interested in trying to make it possible for workers to live outside of London and travel easily to work each day. If people had a cheap and convenient way that they could depend on to go to and from work, they would relocate their homes outside of the city. This would help ease(减轻) the pressure of too many people living in the poor parts of London. From these problems, the idea of the London Underground, the first subway system, was born.

    The plans for building the Underground met with several problems and delays, but the fast track was finally opened in January 1863. A steam train pulled the cars along the fast underground track which was 6 kilometers (3.7 miles) long. About 30,000 people got on the subway the first day. Riders were treated to comfortable seats (standing up while the train was moving was not allowed), and pleasant decorations inside each of the cars. However, the smoke from the engine soon filled the air in the tunnels with ash and soot(煤灰), as well as chemical gases. Fans had to be put in the tunnels later to keep the air clean enough for people to breathe. Even with its problems, riding in the Underground did catch on. It carried 9 million riders in its first year.