Star Wars' Obi-Wan Kenobi said the Force “surrounds us and penetrates us; it binds the galaxy together.” He could have been talking about gravity. Its attractive properties literally bind the galaxy together, but it also “penetrates” us, extending physically through us, keeping us bound to Earth. Unlike the Force, with its dark and light sides, gravity has no duality; it only attracts, never repels. NASA is trying to develop tractor beams that could move physical objects, creating an attractive force that would trump gravity. Passengers on amusement park rides and the International Space Station experience microgravity — incorrectly known as zero gravity — because they fall at the same speed as the vehicles. To leave Earth’s gravitational pull behind, an object must travel 7 miles a second, our planet’s escape velocity. A dime-size magnet has enough electromagnetic force to overcome all of Earth’s gravity and stick to the fridge. Anything with mass warps the space-time surrounding it. In 2011, NASA’s Gravity Probe B experiment showed Earth tugs on the universe around it like a wooden ball spinning in molasses, exactly as Einstein predicted. To understand gravity better, scientists are looking for gravitational waves, ripples in space-time that result from things like black holes colliding and stars exploding, according to Amber Stuver, a physicist at Louisiana’s Laser Interferometer Gravitational-Wave Observatory (LIGO). UMMMM! Who said gravity was easy to understand???
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |