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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The Museum of Science and Industry

    The Manchester Museum of Science and Industry will give us a more wonderful interpretation of the museum. The 2.8 hectare museum was rebuilt on the site of a huge Victorian warehouse and the world's oldest passenger train station. The number and type of collections are ranked first, and in the power exhibition hall, steam engines used during the Industrial Revolution can still be seen. The display of the railway here is rich and vivid in content. Understanding the history of the Industrial Revolution, the Manchester Museum of Science and Industry is a good choice.

    Power is the central theme of the museum, whether it is a bicycle or a steam engine, not to mention an old car. The history of mankind, as this museum shows, has been constantly running. All human inventions can't be separated from this idea. Life is also about exercise. All the exhibits in the museum are alive. The workers oil and wipe every day. Finally, steam is imported into the machinery to make them run as usual as they did a hundred years ago. Time is also reversed.

    In the power exhibition hall, the steam engine that had been used during the Industrial Revolution was still roaring, and the influence was not reduced. If you want to understand the Industrial Revolution and the role of Manchester in it, you must come and visit it, and you will find answers from the many wonderful exhibitions here.

    The Manchester Museum of Science and Industry completely reproduced the British Industrial Revolution, and ensured that the machines of its scientific and technological inventions operated daily, so that visitors and school children could experience the Industrial Revolution. Therefore, the museum has become an outstanding model for preserving industrial heritage.

    Manchester was known as Cotton Capital, Northern Capital, Second City, and Warehouse City for the Industrial Revolution. The Manchester Museum of Science and Industry is located in the center of Manchester City. It records the cradle (摇篮) of the Industrial Revolution with historical details. Manchester City's history, textiles, energy, communications, aviation, transportation and other industries have risen and fallen with the development of science and technology.

    More information: visit https://www.msichicago.org/

    Address: 150 Deansgate Manchester M3 3EH

    Main traffic: Bus 255 to Manchester City Centre

    Open daily: from 10:00 to 17:00

    Tour tickets: free

Tuesday, 1^st September

    I had mixed feelings today, nervous, worried, happy, excited… My heart went down when Miss Chan, our head teacher, said that Matthew and Beth, two students from England, would spend three months with us! I was worried that I had to speak English so much! But at the end of the school day, I was happier than I thought: the morning with them today was more enjoyable than I expected.

    Today is the most unforgettable first day I have had! Matthew is fantastic! His English is clearer and easier to listen to than I thought. The other English student, Beth, is the most helpful girl I've ever met. There were lots of things to do on the first day. Beth offered to help Miss Chan put up all the notices. Of course, some of the credit (功劳) should also go to ME because I translated some of the notices for her. Miss Chan praised us!

    We finished all the preparations 10 minutes earlier than expected, then Beth and I talked for a while, Matthew sang several English songs and did some stand-up comedy (单人喜剧表演) at the party. We all praised him. When the bell rang to end the first school day, none of us wanted to leave.

    When I went back home, I had a little headache. I have probably spoken more English today than the whole of last year.

    It was really a happy day! I hope our friendship can continue, even after they gone back to England!

    City trees grow faster and die younger than trees in rural forestry, a new study finds. Over their lifetimes, then, urban trees will likely absorb less CO₂ from the air thah forest trees.

    As we all know, the earth would be freezing or burning hot without CO₂. However, CO₂ is a greenhouse gas, meaning it traps energy from the sun as/heat. That makes temperatures near the ground rise. Human activities, especially the widespread burning-of fossil(化石)fuels, have been sending extra greenhouse gases into the air. This has led to a rise in average temperatures across the globe.

    Studies had shown forests readily absorb CO₂, but there hadn't been much data on whether city trees grow, die and absorb CO₂ at the same rate as forest trees do. So some researchers decided to find out.

    To figure out how quickly trees were growing, researchers tracked their diameters (the width of their trunks) between 2005 and 2014. A tree's diameter increases as it grows, just as a person's waist size increases as they gain weight. About half the weight of a tree is carbon, research has shown. Most of the rest is water. Over the nine years' tracking, the researchers found city trees absorbed four times as much carbon from the air as forest trees. However, they were twice as likely to die. So over the lifetime of each type of tree, forest trees actually absorbed more CO₂.

    City trees grew faster because they had less competition for light from their neighbors. In a forest, trees tend to grow close together, shading their neighbors. Street trees also benefit from higher levels of nitrogen (氮)in rainwater. Nitrogen helps plants grow. Waste gases from gas-burning cars also contain nitrogen, thus enriching city air with nitrogen. Later, rainwater may wash much of it to the ground. Some street trees may also have better access to water than trees in the country because the underground water pipes can leak.

Adults usually do not remember most of the things that are taught by their teachers at school. But this story is one such lesson that I will never forget. Every time I drift off course, I think of this story.

It was a normal Monday morning, and my teacher was teaching us on important things in life and about devoting ourselves to what is important to us. This is how the story went

An old man lived in a certain part of London, and he would wake up every morning and go to the subway. He would get onto the train right to Central London, and then sit at the street corner and beg. He would do this every single day of his life. He sat at the same street corner and begged for almost 20 years.

His house was dirty, and a stench(恶臭) came out of the house and it smelled terrible. The neighbors could not stand the smell any more, so they called for the police officers to clear the place. The officers knocked down the door and cleaned the house. There were small bags of money all over the house that he had collected over the years.

The police counted the money, and they soon realized that the old man was a millionaire (百万富翁). They waited outside his house expecting to share the good news with him. When the old man arrived home that evening, one of the officers told him that there was no need for him to beg any more as he was a rich man now, a millionaire.

But the old man said nothing at all; he went into his house and locked the door. The next morning he woke up as usual, went to the subway, sat at the street corner and continued to beg.

Clearly, this old man had no great plans, dreams or anything significant for his life. We learn nothing from this story other than staying focused on the things we enjoy doing.