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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    Housework is a frequent source of disputes (争论) between lazy husbands and their hard-working wives, but women have been warned not to expect men to pull their weight any time soon.

    A study from Oxford University has found that men are unlikely to be doing an equal share of housework before 2050. Mothers, the researchers warned, will continue to shoulder the burden of childcare and housework for the next four decades, largely because housework such as cleaning and cooking is still regarded as “women's work”.

    The gap between the amount of time men and women spend on housework has narrowed slowly over the past 40 years. But it will take another four decades before true housework equality (平等) is achieved, the study concluded.

    The research found that in the Nordic countries, the burden of housework is shared more equally between men and women. In the UK, women spend an average of four hours and forty minutes each day on housework, compared with two hours and twenty-eight minutes for men. This is an improvement from the 1960s, when British women typically spent six hours a day on housework, while men spent just 90 minutes every day.

    But progress towards housework equality appears to be slowing in some countries. Dr Oriel Sullivan, a research reader from Oxford's Department of Sociology, said, “we've looked at what is affecting the equality in the home, and we have found that certain tasks seem to be given according to whether they are viewed as ‘men's work' or ‘women's work'.”

    Dr Sullivan said cultural attitudes taught at school may be responsible for the views of housework. “At school it is much easier for a girl to be a tomboy, but it is much more difficult for a boy to enjoy baking and dancing,” she said.

    A spaceship is flying to the sun in summer 2018! It will be the first-ever to a star and will be one of the biggest achievements space exploration (探险) in human history. The purpose is to study the sun's outer atmosphere and better understand how stars work.

The spaceship, with no man inside, will fly within 4 million miles of the sun's surface - right into the solar atmosphere, where the temperature is over 4,500℃. To protect the spaceship, it is covered with a 12cm-thick coating.

    The spaceship is called Parker Solar Probe and it is named after Eugene Parker, a professor from the University of Chicago. It's the first NASA spaceship to be named after a researcher who is still alive. In 1958, Eugene Parker first created the term “solar wind”-the sun sending out a flow of particles (颗粒) and energy.

    “The spaceship is going where it has never been before. It's very exciting that we'll finally get to know more about the solar wind. I'm sure there will be some surprises. There always are,” said Professor Parker.

    Parker calls it a heroic scientific space adventure, and he means that the spaceship will have to experience high temperatures and sun radiation (辐射). “The spaceship is going to do the hottest and fastest work. I love to call it the coolest hottest work under the sun,” said Scientist Fox Nasa.

    Are you interested in hi-tech products? Here are some that you might find at the market pretty soon.

    CX-1

    Tired of dragging your bag through busy airports? Then you might want to consider CX-1. The smart suitcase uses facial recognizing software to follow its owner as he / she is checking in or heading to the gate. Though CX-1 can only move at a speed of up to seven miles per hour, a tiny tool enables owners to keep track of the suitcase's location. It is expected to be sold on the market by late 2018.

    Aibo

    Sony's latest version of the Aibo robotic dog is aslmost as fun as the real thing—but much less work. The pet dog can recognize its owner, obey several commands, and even recall the behavior that pleases its master the most. Aibo can also learn new tricks, take photographs, and over time, develop its own unique personality.

    Forpheus

    Forpheus, an "athletic" robot developed by Japanese technology company Omron. It teaches users how to play ping-pong. The 10-feet-tall machine uses a camera and artificial intelligence to track the ball's speed and can predict the ball's direction correctly. The smart Forpheus can also quickly test its player's abilities and adjust the playing level, making the game fun.

    Black Box VR

    Though many people determine to go to the gym once a week, few reach their goal. Black Box VR wants to change that by turning hard exercise into fun video games. Using it, gym users will find themselves fighting enemies, including big creatures—all while getting exercise.

    A group of scientists is gathering today in the U. K. to discuss a thick piece of ice that's cracking in Antarctica, which is of the size of Delaware.

    The ice shelf is called Larsen C, and it now has a 90-mile crack running through it. The big rift (裂缝) is slicing the ice shelf from top to bottom. But this is not just another sad climate change story. It's more complicated. "A lot of things are going on deep inside the ice," says Adrian Luckman, a glaciologist.

    Luckman says climate change is certainly influencing this region. Larsen C used to have two neighbors to the north, Larsen A and Larsen B. As the air and water warmed, those ice shelves started melting and then disappeared in 1995 and 2002. But the crack in Larsen C seems to have happened on its own, for different reasons.

    Larsen C has many cracks. All ice shelves do. This particular crack has been around since at least the 1960s. The unusual part is that in 2014, this crack — and only this crack — started growing quickly. Why?

    "Well, that is a little bit of a mystery and that's why it drew itself to our attention," says Luckman. One puzzling aspect is how it managed to cut through areas of softer ice that bind (连接) the ice from neighboring glaciers into one giant sheet. Starting in 2014, that soft ice did very little to slow down this rift.

    Scientists are split on how important this crack is for the stability of the whole ice shelf. Some say if this giant section breaks off, it won't make a difference. Others disagree.

    "Ice shelves are the gates of Antarctica in a way, and the gatekeepers of Antarctica. The ice shelves are already floating, so if they fall apart it does not immediately affect sea levels. It's what they hold back -water from all the inland glaciers — that could be problematic. If all the water packed in those glaciers made their way to the sea, it could significantly raise global sea levels," says Ala Khazendar, a geophysicist.

    Put an ice cube from your fridge into a glass of water. You have a piece of string (线) 10 centimeters long. The problem is to take out that piece of ice with the help of the string. But you must not touch the ice with your fingers.

    You may ask your friends to try to do that when you are having dinner together. There is a saltcellar on the table. You must use salt when you carry out this experiment.

    First you put the string across the piece of ice. Then put some salt on the ice. Salt makes ice melt (融化). The ice round the string will begin to melt. But when it melts, it will lose heat. The cold ice cube will make the salt water freeze again.

    After a minute or two you may raise the piece of string and with it you will raise your piece of ice!

    This experiment can be very useful to you. If, for example, there is ice near the door of your house, you must use very much salt to melt all the ice. If you don't put enough salt, the water will freeze again.