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    The next time someone asks you where the biggest ocean is, point them toward Jupiter. While earth harbours about 320 million cubic miles(1,333 cubic km)of water, our planet is practically a desert compared to the rest of the Solar System.

    A moon of Jupiter called Europa, for example, which is roughly the size of our own Moon, likely hides a subsurface ocean with more than twice as much water as there is on Earth.

    Yet even that pales into insignificance in comparison to Europa's neighbour Ganymede; more than 30 times as much water as our home planet is thought to reside there as liquid and ice.

    And scientists keep finding more water wherever they look. On September 28, researchers reported that Dione — a small moon of Saturn — probably has a subsurface ocean, too.

    To see just how Earth stacks up against other ocean worlds, Business Insider contacted Steve Vance, a planetary scientist at NASA's Jet Propulsion Laboratory who's calculated the numbers on just how much water might be out there.

    In order of how much water they have, from the least to the most, they are: Enceladus, Dione, Earth, Europa, Pluto, Triton, Callisto, Titan, and Ganymede. Mimas, a moon of Saturn, and Ceres, the largest asteroid in the Solar System, are also thought to have subsurface oceans —but scientists aren't yet sure how big each one might be.

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    I was never very neat, while my roommate Kate was extremely organized. Each of her objects had its place, but mine always hid somewhere. She even labeled(贴标签) everything. I always looked for everything. Over time, Kate got neater and I got messier. She would push my dirty clothing over, and I would lay my books on her tidy desk. We both got tired of each other.

    War broke out one evening. Kate came into the room. Soon, I heard her screaming, “Take your shoes away! Why under my bed!” Deafened, I saw my shoes flying at me. I jumped to my feet and started yelling. She yelled back louder.

    The room was filled with anger. We could not have stayed together for a single minute without a phone call. Kate answered it. From her end of the conversation, I could tell right away her grandma was seriously ill. When she hung up, she quickly crawled(爬) under her covers, weeping. Obviously, that was something she should not go through alone. All of a sudden, a warm feeling of sympathy rose up in my heart,

    Slowly, I collected the pencils, took back the books, made my bed, cleaned the socks and swept the floor, even on her side. I got so into my work that I even didn't noticed Kate had sat up. She was watching, her tears dried and her expression one of disbelief. Then, she reached out her hands to grasp mine. I looked up into her eyes. She smiled at me. “Thanks.”

    Kate and I stayed roommates for the rest of the year. We didn't always agree, but we learned the key to living together: giving in, cleaning up and holding on.

    The Winter Olympics are also called The White Olympics. At this time, many colorful stamps are published to mark the great Games. The first stamps marking the opening came out on January 25th,1932 in the United States for the 3rd White Olympics. From then on, publishing stamps during the White Olympics became a rule. During the 4th Winter Olympics, a group of stamps were published in Germany in November 1936. The five rings of Olympics were drawn on the front of sportswear. It was the first time that the rings appeared on the stamps of the White Olympics.

In the 1950's, stamps of this kind became more colorful. When the White Olympics came, the host countries as well as the non-host(非主办方)countries published stamps to mark those Games. China also published four stamps in February 1980, when the Chinese sportsmen began to take part in the White Olympics.

    Japan is the only Asian country that has ever held the White Olympics. Altogether 14,500 million stamps were sold to raise money for this sports meeting.

    Different kinds of sports were drawn on these small stamps. People can enjoy the beauty of the wonderful movements of some sportsmen.

    When one tried to unify gravity with quantum mechanics (量子力学), one had to introduce the idea of 'imaginary' time. If one can go forward in imaginary time, one ought to be able to turn round and go backward. This means that there can be no important difference between the forward and backward directions of imaginary time. Yet there is a big difference between the forward and backward directions of 'real time' in ordinary life. Imagine a cup of water falling off a table and breaking into pieces on the floor. If you take a film of this, you can easily tell whether it is being run forward or backward. You can tell that the film is being run backward because this kind of behavior is never observed in ordinary life.

    The explanation that is usually given as to why we don't see broken cups gathering themselves together off the floor and jumping back onto the table is that it is forbidden by the second law of thermodynamics (热力学). This says that in any closed system disorder, or entropy (熵), always increases with time. In other words, it is a form of Murphy's law: things always tend to go wrong! An intact cup on the table is a state of high order, but a broken cup on the floor is a disordered state. One can go readily from the cup on the table in the past to the broken cup on the floor in the future, but not the other way round.

    The increase of disorder or entropy with time is one example of what is called an arrow of time, something that tells the past from the future, giving a direction to time. There are at least three different arrows of time. First, there is the thermodynamic arrow of time, the direction of time in which disorder or entropy increases. Then, there is the psychological arrow of time. This is the direction in which we feel time passes, the direction in which we remember the past but not the future. Finally, there is the cosmological arrow of time. This is the direction of time in which the universe is expanding rather than contracting.

    Doctors say you had better use it before you lose it. The more you sit each day, the more chance you have of getting sick.

    Richard Rosenkranz of Kansas State University was among the researchers. He said people who sat for long periods were at great risk of diseases when compared with those who sat less. He said that was especially true for some chronic (慢性的) diseases.

    Richard Rosenkranz studied the relationship between sitting and chronic diseases in middle-aged Australian men. He worked with researchers from the University of Western Sydney. They examined the health records of more than 63,000 men from New South Wales. The men were between the ages of 45 and 65. The men reported about what diseases they had, or did not have. And they kept record of the amount of time each day that they sat.

    The study also showed that exercising every morning for 30minutes did not reduce the health risk if you spend the next eight hours sitting at the desk. Mr. Rosenkranz said it was important to make sure you exercise. But he said it was also important to find ways not to sit so much during the day.

    Many jobs today require sitting and working at the desk all day. James Levine works at the Mayo Clinic in the United Sates. He suggests working while standing at high table some of the time instead of sitting at a desk. Dr. Levine also suggests standing while using the telephone or eating. Or he advises walking with the people you work with for an on-foot meeting. And he notes that if you spend more time on your feet, you may have muscle activity that helps burn fats and sugars in your body.