Learn more about gravity and micro gravity. In this video you will also learn about the researches to understand micro gravity.
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From the dawn of time, we have continuously worked our ways to improve our creations. Artisans, manufacturers, scientists and engineers have for centuries manipulated the materials they work with to produce better products. Experimentation has included changing or controlling such elements as temperature, pressure and composition to achieve steps forward for innovation. However, for all the manipulation and control, these inventors exerted over their productions the constant pull of gravity was one element they were unable to subjugate. Gravity is a constant force and an invisible element that controls the way many of the things we use in life and work. But where scientific research is concerned, gravity can impose many restrictions. Scientific experiments involving fluids whereby components such as sedimentation, fluid density; buoyancy and temperature differences are examined are severely limited on earth. This is why experiments in micro gravity are ideal for fluid experimentations as the low gravity effectively eliminates sedimentation and buoyancy issues. This space shuttle contains a space-based laboratory and presents scientists with a new environment in which to conduct the experiments. Because the environment is in a situation of microgravity, gravity is no longer a constant force for experiments. This results in a whole new range of research opportunities available to scientists in many fields of study. Astronauts are often described to be experiencing zero gravity in space. The term however is technically incorrect, as even at 300 km into space, gravity still exercises 90% of the attractive force it has at the earth’s surface. The concept of microgravity is a simple one. Once the shuttle reaches its orbit above earth, it is traveling at a fast enough speed to maintain a continuous freefall effect. This freefall environment in turn creates the microgravity conditions that make things appear as they were floating when in actual fact, they are falling. We experience microgravity when bouncing on trampolines, riding roller coasters or diving off a diving board. Over 200 years ago, inventor William Watts discovered that he could produce superior—by dropping molten lead from a tall tower. Since then, scientists have carried on this concept with experiments conducted in taller, more sophisticated drop towers or in research aircraft such as NASA’s KC-135 or suborbital rockets. But even with such advances in technology, periods of freefall are still limited to less than 10 minutes. On the space shuttle however, scientists can experience more than two weeks of microgravity. The International Space Station is a more permanent microgravity research facility which can host experiments for long periods of time and could facilitate experiments into areas such as fluid physics. On earth, liquid is considered as drops, streams, puddles or even just a shape of the container it is occupying. In microgravity however, liquid has a completely different physical characteristics. No longer bound by the abundant gravity of earth, surface tension reigns allowing the liquid to form into a near perfect sphere. It becomes a self-contained vial of liquid freefalling with the rest of the shuttle’s cargo. This fluid physics experiment on the sphere of liquid uses the drop physics model. The drop itself is suspended due to the freefalling effect. The movement is caused by sound waves which are being use to maneuver the drop. One of a kind experiment such as these gives fluid physicists an opportunity to test hypothesis that were formulated on earth.
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