{"page":"\u003clink rel=\"stylesheet\" href=\"https://lessonplanet.com/assets/packs/css/resources-c03aa079.css\" /\u003e\n\u003clink rel=\"stylesheet\" href=\"https://lessonplanet.com/assets/packs/css/lp_boclips_stylesheets-517835be.css\" media=\"all\" /\u003e\n\u003cdiv data-title='What Is Dark Matter? Exploring One of Physics’ Biggest Mysteries' data-url='/boclips/videos/689a05560afbd36b8e260b64' data-video-url='/boclips/videos/689a05560afbd36b8e260b64' id='bo_player_modal'\u003e\n\u003cdiv class='boclips-resource-page modal-dialog panel-container'\u003e\n\u003cdiv class='react-notifications-root'\u003e\u003c/div\u003e\n\u003cdiv class='rp-header'\u003e\n\u003cdiv class='rp-type'\u003e\n\u003ci aria-hidden='true' class='fai fa-regular fa-circle-play'\u003e\u003c/i\u003e\nVideo\n\u003c/div\u003e\n\u003ch1 class='rp-title' id='video-title'\u003e\nWhat Is Dark Matter? Exploring One of Physics’ Biggest Mysteries\n\u003c/h1\u003e\n\u003cdiv class='rp-actions'\u003e\n\u003cdiv class='mr-1'\u003e\n\u003ca class=\"btn btn-success\" data-posthog-event=\"Signup: LP Signup Activity\" data-posthog-location=\"body_link_boclips\" data-remote=\"true\" href=\"/subscription/new\"\u003e\u003cspan\u003e\u003cspan\u003eGet Free Access\u003c/span\u003e\u003cspan class=\"\"\u003e for 10 Days\u003c/span\u003e\u003cspan\u003e!\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv class='rp-body'\u003e\n\u003cdiv class='rp-info'\u003e\n\u003cdiv aria-label='Hide resource details' class='rp-hide-info' role='button' tabindex='0'\u003e\u0026times;\u003c/div\u003e\n\u003ci aria-label='Expand resource details' class='rp-expand-info fai fa-solid fa-up-right-and-down-left-from-center' role='button' tabindex='0'\u003e\u003c/i\u003e\n\u003ci aria-label='Compress resource details' class='rp-compress-info fai fa-solid fa-down-left-and-up-right-to-center' role='button' tabindex='0'\u003e\u003c/i\u003e\n\u003cdiv class='rp-rating'\u003e\n\u003cspan class='resource-pool'\u003e\n\u003cspan class='pool-label'\u003ePublisher:\u003c/span\u003e\n\u003cspan class='pool-name'\u003e\n\u003cspan class='text'\u003e\u003ca data-publisher-id=\"30356011\" href=\"/search?publisher_ids%5B%5D=30356011\"\u003eCurated Video\u003c/a\u003e\u003c/span\u003e\n\u003c/span\u003e\n\u003c/span\u003e\n\u003c/div\u003e\n\u003cdiv class='rp-description'\u003e\n\u003cspan class='short-description'\u003eWhat is Dark Matter? -- What if I told you that there may be trillions of particles going through your body right now, and you can’t see it, hear it, or touch it.  And that these particles are so vast, that they compose more than 6 times...\u003c/span\u003e\n\u003cspan class='full-description hide'\u003eWhat is Dark Matter? -- What if I told you that there may be trillions of particles going through your body right now, and you can’t see it, hear it, or touch it.  \u003cbr/\u003e\u003cbr/\u003eAnd that these particles are so vast, that they compose more than 6 times all the visible matter you can see in the universe.  \u003cbr/\u003e\u003cbr/\u003e6 times all the stars, galaxies, planets, gases, and radiation.  \u003cbr/\u003e\u003cbr/\u003eAnd we not only cannot see any of it with our eyes, we cannot detect it with any of our instruments.  \u003cbr/\u003e\u003cbr/\u003eSo how the heck do we know that it’s even there?  \u003cbr/\u003e\u003cbr/\u003eIn the late 1970’s, an astronomer by the name of Vera Rubin, who happened to be a female in a male-dominated profession, was studying a mundane area of astronomy that no one else seemed to be interested in at the time.\u003cbr/\u003e\u003cbr/\u003eShe was looking at the motion of stars in the spiral portions of the Andromeda galaxy, a neighbor of our own milky way galaxy.\u003cbr/\u003e\u003cbr/\u003eWhat she found shocked scientists…because it seemed to violate Newton’s laws of gravitation which had been established as scientific law for the previous 300 years. \u003cbr/\u003e\u003cbr/\u003eHer observations showed that the stars in the outer rim of the spiral arms were moving at about the same velocity as the stars in the inner part of the spiral arm.\u003cbr/\u003e\u003cbr/\u003eThis violates Newton’s law of universal gravitation which should govern both the motion of stars in galaxies as well as the motion of planets around the sun.\u003cbr/\u003e\u003cbr/\u003eForce of Gravity = G m1 m2 / r2\u003cbr/\u003em1= mass of first planet\u003cbr/\u003em2 = mass of second planet\u003cbr/\u003er2= square of distance between them\u003cbr/\u003eG = Gravitational constant\u003cbr/\u003e\u003cbr/\u003eThe equations dictate that the further away an object is from the center of mass (r), the lower the force of gravity, and the slower the object rotates around it.  \u003cbr/\u003e\u003cbr/\u003eStars closer to the center must travel faster than those away from the center.\u003cbr/\u003e\u003cbr/\u003eOtherwise, the stars would fly away from their orbits around the galaxy.\u003cbr/\u003e\u003cbr/\u003eThis is easy to see in the motion of all the planets in our own solar system – which follow Newton’s laws pretty much to the letter.\u003cbr/\u003e\u003cbr/\u003eVera Rubin found that this was not the case with the stars in the Andromeda galaxy.  And since then, scientists have found that the stars in all observable galaxies, including our own milky way, move in the same perplexing fashion.\u003cbr/\u003e\u003cbr/\u003eThe only possible way that stars in galaxies can move this way is if there was a lot more mass on the arms of the galaxies than we can see.\u003cbr/\u003e\u003cbr/\u003eVera Rubin’s observations confirmed an earlier 1933 hypothesis proposed by Swiss-American astronomer Fritz Zwicky that the universe contains a lot more mass than we can see with our telescopes.\u003cbr/\u003e\u003cbr/\u003eThe only problem was, and continues to be today, 40 years later, is that we cannot see any of this matter, it emits no light, no radiation of any sort, and it does not appear to interact in any way with ordinary matter except through gravity.\u003cbr/\u003e\u003cbr/\u003eIt only emits is gravity.  We can observe the behavior of stars and the bending of light due to the immense gravity of this unknown substance.\u003cbr/\u003e\u003cbr/\u003eAn “unknown” in physics is usually labeled Dark.  Hence this is why this substance is called “Dark Matter”  \u003cbr/\u003e\u003cbr/\u003eAnd it turns out that this dark matter has at least 6 times as much gravity as all the observable and detectable matter in the universe.  \u003cbr/\u003e\u003cbr/\u003eSo the vast majority of the matter in the universe is dark matter – about 85%.  And it cannot be seen or detected (except by its gravity).\u003cbr/\u003e\u003cbr/\u003eThe things we CAN see is like the foam on top of the waves of the ocean, but we are not able to see waves or the ocean itself.  We and our instruments are blind to it.\u003cbr/\u003e\u003cbr/\u003eWe are living in the mere foam of the waves on the ocean which is the real universe.\u003c/span\u003e\n\u003c/div\u003e\n\u003cdiv class='action-container flex justify-between'\u003e\n\u003cbutton aria-expanded='false' aria-label='Read more description' class='rp-full-description' type='button'\u003e\n\u003ci class='fai fa-solid fa-align-left'\u003e\u003c/i\u003e\n\u003cspan id='read_more'\u003eRead More\u003c/span\u003e\n\u003c/button\u003e\n\u003cdiv class='rp-report'\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv aria-labelledby='resource-details-heading' class='rp-info-section'\u003e\n\u003ch2 class='title' id='resource-details-heading'\u003eResource Details\u003c/h2\u003e\n\u003cdiv class='rp-resource-details clearfix'\u003e\n\u003cdiv class='detail'\u003e\n\u003cdl\u003e\n\u003cdt\u003eCurator Rating\u003c/dt\u003e\n\u003cdd\u003e\u003cspan class=\"star-rating\" aria-label=\"4.0 out of 5 stars\" 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