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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    Body language is one of the most powerful means of communication, often even more powerful than spoken language. It is said that our body movements communicate about 50 percent of what we really mean while words only express 7 percent. So, while your mouth is closed, your body is just saying.

    Arms. How you hold your arms shows how open and receptive you are to people you meet. If you keep your arms to the sides of your body or behind your back, this suggests you are not afraid of taking on whatever comes your way. Outgoing people generally use their arms with big movements, while quieter people keep them close to their bodies. If someone upsets you, just cross your arms to show you're unhappy!

    Head. When you want to appear confident, keep your head level. If you are a monitor in class, you can also take on this position when you want your words to be taken seriously. However, to be friendly in listening or speaking, you must move your head a little.

    Legs. Your legs tend to move around a lot more than normal when you are nervous or telling lies. If you are at interviews, try to keep them still!

    Posture (姿势). A good posture makes you feel better about yourself. If you are feeling down, you normally don't sit straight, with your shoulders inwards. This makes breathing more difficult, which can make you feel nervous or uncomfortable.

    Mouth. When you are thinking, you often purse(噘嘴) your lips. You might also use this position to hold back an angry comment you don't wish to show. However, it will probably still be noticed, and people will know you're not pleased.

    Face. When you lie, you might put on a false face. But that expression would crack briefly, allowing displays of true emotions such as happiness, sadness, disgust (厌恶) and fear to come through.

Discovery's astronauts arrived to an exciting celebration Wednesday as nearly 700 people crowded an airplane storage place, waving flags and holding signs that read: “Welcome Home, Astronauts!”

    The seven-person team returned to Earth on Tuesday after being the first to take a space shuttle into orbit since the Columbia disaster（灾难）of 2003. 

    “In the last two and a half years, we have been through the very worst that manned space flight can bring us, and over the past two weeks we have seen the very best,” NASA Administrator Michael Griffin told the astronauts and their families and fans Wednesday. 

    The crowd waved American flags for the U.S. astronauts and Japanese flags for crew member Soichi Noguchi, one of the spacewalkers. 

    “As a rookie（新手）astronaut, I could not ask for more,” Noguchi said, “We had three spacewalks, two extra days in space and one great team.” 

    While the homecoming has been filled with excitement for what mission controllers declared a “truly spectacular test flight”, uncertainty remains for the future of the shuttle program. 

    Shortly after Discovery rose up into space July 26, a nearly 1-pound large piece of foam insulation（泡沫绝缘材料）fell from the fuel tank-the very thing that was supposed to have been fixed after Columbia exploded. The foam missed Discovery, but NASA grounded all shuttle flights until engineers fix the problem.

    NASA ground crews examined Discovery after its return from orbit and found it in good condition, an official said Wednesday at NASA‟s Dryden Flight Research Center at Edwards Air Force Base in California. 

    Technicians counted 101 dings and divots, including 20 that were larger than 1 inch. Schaaf Dean, landing support group chief, said the numbers were similar to the results of other shuttle, post-landing examinations. 

A beginning examination of the shuttle's thermal（热的）blanket showed it remained undamaged during re-en-try into the Earth's air.(Agencies)

    So you want to be a citizen scientist? The National Science Foundation (NSF) has got you covered. NSF supports citizen science across all areas of science, whether your passion is to scan the night sky, or explore your own backyard.

Join a flock of birders

    eBird is an online platform that allows bird-watchers to go online and record their sightings to a database. With more than 100,000 active users, eBird's system is a treasure of information on bird population, distribution and habitat, which users can explore in real time.

Count every drop

    The Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) is the largest provider of daily precipitation observations in the United States. Volunteers set up rain gauges and record data every time a rain, snow or hail storm passes over. Data is organized and shared on the CoCoRaHS website, and used by scientists, farmers and more.

Search for stars with your computer

    Einstein@Home uses your computer's idle time to search for space signals. The project has already had major successes: Volunteers discovered about 50 stars, using data from Puerto Rico's Arecibo Observatory and Australia's Parkes Observatory. Einstein@Home also searches for gravitational-wave signals using data from NSF's Laser Interferometer Gravitational Wave Observatory.

Be part of a supercomputer

    To link all those home computers, Einstien@Home uses software called the Berkeley Open Infrastructure for Network Computing, better known as BOINC. The software choreographs(安排，筹划) the technical aspect of volunteer computing and helps you use radio telescope signals to search for alien life.

Join the plankton party

    Without plankton, life in the ocean would not exist. These tiny organisms form the base of the food chain, and play an important role in the global carbon cycle. Plankton Portal enlists citizen scientists to identify images of plankton, snapped by the In Situ Icthyoplankton Imaging System (ISIIS), an underwater robot engineered at the University of Miami. ISIIS has taken millions of images in oceans around the world and upload them into a database; classifying the images helps researchers understand plankton diversity, habitat and behavior.

    Traditional Chinese medicine (TCM) is gaining global popularity. According to a government white paper, TCM has been introduced in 183 countries and regions around the world.

    Westerners' understanding of TCM, however, may be limited to acupuncture, cupping and massage(针灸，拔罐和按摩). For instance, the purple, injury-like marks left on U. S. swimmer Michael Phelps，back from cupping for the purpose of relaxing his muscles and reducing pain became the center of attention during the Rio Olympics in 2016.

    As a matter of fact, Chinese herbs play a more important role in getting rid of diseases and keeping the body in good condition in the TCM treatment system than physical treatment. It is therefore disheartening to know that while 103 World Health Organization member countries have given approval to the practice of acupuncture, not many recognize Chinese herbal medicine. TCM falls far behind Western medicine owing partly to the slow development of Chinese herbs.

    Herbs are made into pills, powder and soup, and the kind of herbs used, their quality and quantity, and the processing of the ingredients (原材料) jointly determine the effectiveness of the prescription. Compared with Western medicine, which has standardized drug production processes and treatment methods, TCM lacks standardization, with the chemical composition and functions of its medicines being unclear and their effects being unstable. Fortunately, standardization has improved in recent decades, with an increasing number of factories producing patented TCM drugs.

    Another factor that has prevented the development of TCM prescription drugs is the lack of creativity. While Western medicine-making companies come up with new products every year, TCM drug producers tend to make medicines according to prescriptions handed down from the past. Chinese chemist Tu Youyou's winning the 2015 Nobel Prize in Physiology or Medicine for her research into malaria (疟疾) treatment may drive creativity to some extent in China's TCM industry. However, the current state of affairs cannot be changed within a short time.

    Here are some great people and their achievements.

    Mary Anderson ­ windscreen wiper.

    Back on a freezing winter's day in 1902, Mary Anderson was travelling by train through New York City. Snow was falling, forcing the driver to stop repeatedly and get out to clear it. Each time the door opened, Mary suffered a gust of sub-zero air. She had an idea: why not make some kind of a rubber blade that could be operated from inside the vehicle? And that's exactly what she did.

    Josephine Cochrane ­ dishwasher

    The dishwasher dates back even earlier to the 19th century, and to the dinner parties thrown by a lady called Josephine Cochrane. As a frequent host, she wanted a machine that could wash dishes faster than people. Her response was to develop what was to become the first commercially successful dishwasher. Interestingly, innovation was in her blood: her grandfather had invented the steamboat.

    Stephanie Kwolek ­ Kevlar

    Kevlar is the lightweight fibre used in bulletproof vests. The material is used by millions every day and has saved countless lives. The super tough fabric is also used in objects ranging from gloves to airplanes. Incredibly, its strength-to-weight ratio(比强度) is five times higher than steel. Again, it was invented by a woman, the American chemist Stephanie Kwolek, in 1964.

    Grace Hopper ­ first compiler(编译程序)

    One of the most important inventions of the 20th century must surely be the computer programme. The world of programming is unbalanced in terms of gender. Men vastly outnumber women, and take home around 30% more pay than their female counterparts on average. But back in the 1940s and 1950s, women were at the forefront of this new field. Grace Hopper is credited with inventing the first compiler in 1952, which serves as the bridge between code and the binary(二进制的) ones and zeros understood by computers.