subtitle/0w4OTD4L0GQ.srt

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<font color="white" size=".72c">[Music]</font>

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<font color="white" size=".72c">what are you doing right now</font>

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<font color="white" size=".72c">if you're watching this video chances</font>

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<font color="white" size=".72c">are you'll be sitting down</font>

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<font color="white" size=".72c">somewhere and when you're sat down</font>

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<font color="white" size=".72c">you're stationary</font>

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<font color="white" size=".72c">right wrong well</font>

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<font color="white" size=".72c">sort of wrong while you may be</font>

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<font color="white" size=".72c">stationary on earth's surface</font>

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<font color="white" size=".72c">right now earth itself is moving</font>

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<font color="white" size=".72c">hurtling through space</font>

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<font color="white" size=".72c">at speeds of around 30 kilometers</font>

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<font color="white" size=".72c">per second</font>

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<font color="white" size=".72c">[Music]</font>

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<font color="white" size=".72c">similarly the sun is also moving at</font>

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<font color="white" size=".72c">speeds of around 220 kilometers per</font>

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<font color="white" size=".72c">second</font>

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<font color="white" size=".72c">dragging our entire solar system with it</font>

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<font color="white" size=".72c">as it orbits the galactic tide of the</font>

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<font color="white" size=".72c">milky way</font>

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<font color="white" size=".72c">[Music]</font>

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<font color="white" size=".72c">of course we don't feel either of these</font>

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<font color="white" size=".72c">movements</font>

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<font color="white" size=".72c">gravity keeps us bolted down for the</font>

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<font color="white" size=".72c">ride</font>

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<font color="white" size=".72c">but elsewhere in space and given enough</font>

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<font color="white" size=".72c">time</font>

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<font color="white" size=".72c">everything moves and everything flows</font>

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<font color="white" size=".72c">nothing remains stationary in space</font>

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<font color="white" size=".72c">but what is it that makes the galaxy</font>

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<font color="white" size=".72c">move</font>

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<font color="white" size=".72c">well that's going to be our topic today</font>

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<font color="white" size=".72c">and it makes for one of astronomy's most</font>

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<font color="white" size=".72c">intriguing mysteries</font>

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<font color="white" size=".72c">as you are watching this video</font>

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<font color="white" size=".72c">everything in our local universe for</font>

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<font color="white" size=".72c">millions of light years</font>

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<font color="white" size=".72c">including the milky way and the local</font>

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<font color="white" size=".72c">group is being dragged through space</font>

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<font color="white" size=".72c">pulled through the void towards a</font>

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<font color="white" size=".72c">gravitational focal point which we</font>

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<font color="white" size=".72c">cannot see</font>

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<font color="white" size=".72c">and whatever it is it exerts an</font>

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<font color="white" size=".72c">astonishing</font>

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<font color="white" size=".72c">almost godlike influence on the vast</font>

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<font color="white" size=".72c">swathes of space around it</font>

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<font color="white" size=".72c">it is the mystery of the great attractor</font>

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<font color="white" size=".72c">the milky way is a vast ancient and</font>

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<font color="white" size=".72c">structured collection</font>

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<font color="white" size=".72c">of hundreds of billions of stars known</font>

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<font color="white" size=".72c">as a galaxy</font>

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<font color="white" size=".72c">the universe is teeming with them many</font>

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<font color="white" size=".72c">larger and more densely packed with</font>

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<font color="white" size=".72c">stars than our own</font>

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<font color="white" size=".72c">and when this many stars come together</font>

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<font color="white" size=".72c">gravity allows them to work as a</font>

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<font color="white" size=".72c">coherent structure</font>

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<font color="white" size=".72c">with a much stronger gravitational</font>

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<font color="white" size=".72c">influence</font>

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<font color="white" size=".72c">galaxies are so incredibly massive that</font>

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<font color="white" size=".72c">they can attract one another from</font>

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<font color="white" size=".72c">millions of light years across space</font>

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<font color="white" size=".72c">sometimes getting close enough to</font>

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<font color="white" size=".72c">collide producing new larger galaxies</font>

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<font color="white" size=".72c">however the space between galaxies is</font>

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<font color="white" size=".72c">significantly more voluminous than the</font>

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<font color="white" size=".72c">galaxies themselves</font>

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<font color="white" size=".72c">and there is another force at work space</font>

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<font color="white" size=".72c">itself is expanding</font>

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<font color="white" size=".72c">including the space between galaxies</font>

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<font color="white" size=".72c">which pushes them apart</font>

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<font color="white" size=".72c">faster than they can attract one another</font>

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<font color="white" size=".72c">spreading the contents of the universe</font>

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<font color="white" size=".72c">more sparsely</font>

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<font color="white" size=".72c">this is known as the hubble flow</font>

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<font color="white" size=".72c">galaxies are for the most part</font>

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<font color="white" size=".72c">receding away from all other galaxies</font>

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<font color="white" size=".72c">uniformly as the universe grows</font>

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<font color="white" size=".72c">consequently most galaxies are not close</font>

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<font color="white" size=".72c">enough to collide with their neighbours</font>

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<font color="white" size=".72c">only very small localized pockets of</font>

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<font color="white" size=".72c">space like our local group</font>

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<font color="white" size=".72c">will be dense enough to collapse into a</font>

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<font color="white" size=".72c">single structure</font>

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<font color="white" size=".72c">however while they may not be destined</font>

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<font color="white" size=".72c">to collide</font>

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<font color="white" size=".72c">dense concentrations of galaxies can</font>

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<font color="white" size=".72c">still exert influences on one another</font>

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<font color="white" size=".72c">bringing them close enough that the</font>

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<font color="white" size=".72c">combined gravitational potential of the</font>

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<font color="white" size=".72c">galaxies</font>

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<font color="white" size=".72c">attracts more remote galaxies creating</font>

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<font color="white" size=".72c">denser concentrations and emptying out</font>

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<font color="white" size=".72c">the space in between in a</font>

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<font color="white" size=".72c">self-sustaining process</font>

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<font color="white" size=".72c">this forms the overarching structure</font>

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<font color="white" size=".72c">that stretches across our entire</font>

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<font color="white" size=".72c">universe</font>

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<font color="white" size=".72c">the cosmic web kind of like a sponge</font>

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<font color="white" size=".72c">there are areas of matter which branch</font>

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<font color="white" size=".72c">in every direction</font>

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<font color="white" size=".72c">and large empty swathes in between</font>

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<font color="white" size=".72c">the cosmic web is composed of enormous</font>

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<font color="white" size=".72c">walls of interacting galaxies</font>

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<font color="white" size=".72c">known as galaxy filaments and these can</font>

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<font color="white" size=".72c">contain hundreds of thousands of</font>

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<font color="white" size=".72c">galaxies</font>

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<font color="white" size=".72c">and span over billions of light years</font>

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<font color="white" size=".72c">the galaxies within these filaments</font>

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<font color="white" size=".72c">migrate through paths within the</font>

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<font color="white" size=".72c">structure</font>

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<font color="white" size=".72c">and streams of interacting galaxies flow</font>

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<font color="white" size=".72c">converge and diverge like great cosmic</font>

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<font color="white" size=".72c">water flows over distances difficult to</font>

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<font color="white" size=".72c">comprehend</font>

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<font color="white" size=".72c">the individual thread-like components of</font>

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<font color="white" size=".72c">a galaxy filament are known as galaxy</font>

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<font color="white" size=".72c">clusters and superclusters</font>

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<font color="white" size=".72c">smaller groupings of tens hundreds or</font>

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<font color="white" size=".72c">perhaps thousands of galaxies</font>

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<font color="white" size=".72c">which are more concentrated than the</font>

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<font color="white" size=".72c">overall density of the filament</font>

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<font color="white" size=".72c">and thus have more substantial</font>

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<font color="white" size=".72c">interactions with one another</font>

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<font color="white" size=".72c">in truth the lines between clusters</font>

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<font color="white" size=".72c">superclusters and filaments are slightly</font>

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<font color="white" size=".72c">fuzzy</font>

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<font color="white" size=".72c">primarily because we didn't realize that</font>

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<font color="white" size=".72c">galaxy structures of filament size could</font>

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<font color="white" size=".72c">exist when we coined</font>

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<font color="white" size=".72c">the other terms we knew galaxies could</font>

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<font color="white" size=".72c">cluster up</font>

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<font color="white" size=".72c">but we never thought that they would be</font>

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<font color="white" size=".72c">able to interact over billions of light</font>

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<font color="white" size=".72c">years</font>

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<font color="white" size=".72c">how wrong we were</font>

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<font color="white" size=".72c">over the past 40 years we have managed</font>

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<font color="white" size=".72c">to build up a comprehensive</font>

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<font color="white" size=".72c">three-dimensional map</font>

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<font color="white" size=".72c">of intergalactic space and we now know a</font>

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<font color="white" size=".72c">considerable amount about our</font>

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<font color="white" size=".72c">large-scale surroundings</font>

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<font color="white" size=".72c">not bad for a tiny world existing in the</font>

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<font color="white" size=".72c">blink of an eye on a galactic time scale</font>

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<font color="white" size=".72c">we know that our local group which</font>

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<font color="white" size=".72c">contains us andromeda the triangulum</font>

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<font color="white" size=".72c">galaxy</font>

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<font color="white" size=".72c">and more than 100 other small satellite</font>

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<font color="white" size=".72c">dwarf galaxies</font>

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<font color="white" size=".72c">is situated in a relatively outlying</font>

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<font color="white" size=".72c">region to a cluster of more than 1</font>

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<font color="white" size=".72c">300 galaxies known as the virgo cluster</font>

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<font color="white" size=".72c">this cluster happens to be the</font>

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<font color="white" size=".72c">gravitational core of a much larger</font>

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<font color="white" size=".72c">colony</font>

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<font color="white" size=".72c">containing over a hundred galaxy groups</font>

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<font color="white" size=".72c">like ours</font>

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<font color="white" size=".72c">called the virgo supercluster one of</font>

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<font color="white" size=".72c">more than an</font>

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<font color="white" size=".72c">estimated 10 million galaxy</font>

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<font color="white" size=".72c">superclusters in the observable universe</font>

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<font color="white" size=".72c">the virgo supercluster extends over an</font>

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<font color="white" size=".72c">area of more than 110</font>

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<font color="white" size=".72c">million light years and it is thought to</font>

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<font color="white" size=".72c">be over 7 thousand times as massive as</font>

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<font color="white" size=".72c">the local group</font>

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<font color="white" size=".72c">enough to exert a considerable influence</font>

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<font color="white" size=".72c">on its intergalactic neighborhood</font>

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<font color="white" size=".72c">but the cluster network doesn't end here</font>

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<font color="white" size=".72c">either</font>

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<font color="white" size=".72c">a groundbreaking study in 2014</font>

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<font color="white" size=".72c">published by scientists at the</font>

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<font color="white" size=".72c">university of hawaii</font>

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<font color="white" size=".72c">revealed that the virgo supercluster is</font>

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<font color="white" size=".72c">just one component of an even</font>

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<font color="white" size=".72c">greater network of almost unknowable</font>

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<font color="white" size=".72c">intricacy and scale</font>

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<font color="white" size=".72c">our home galactic supercluster laniakea</font>

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<font color="white" size=".72c">[Music]</font>

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<font color="white" size=".72c">the lanikia supercluster extends over</font>

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<font color="white" size=".72c">half a billion light years across</font>

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<font color="white" size=".72c">space and is home to more than a hundred</font>

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<font color="white" size=".72c">thousand</font>

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<font color="white" size=".72c">galaxies it is so vast</font>

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<font color="white" size=".72c">that for a long time we didn't realize</font>

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<font color="white" size=".72c">that its constituent superclusters were</font>

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<font color="white" size=".72c">connected</font>

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<font color="white" size=".72c">laniakia consists of four main galaxy</font>

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<font color="white" size=".72c">superclusters</font>

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<font color="white" size=".72c">us and the rest of the virgo</font>

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<font color="white" size=".72c">supercluster the hydra centaurus</font>

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<font color="white" size=".72c">supercluster</font>

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<font color="white" size=".72c">the parvo indus supercluster and the</font>

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<font color="white" size=".72c">southern supercluster</font>

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<font color="white" size=".72c">and despite their enormous cosmic</font>

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<font color="white" size=".72c">distances from each other</font>

197
00:07:41,280 --> 00:07:46,720
<font color="white" size=".72c">they interlink to create a plethora of</font>

198
00:07:43,520 --> 00:07:46,720
<font color="white" size=".72c">flows across space</font>

199
00:07:47,120 --> 00:07:50,159
<font color="white" size=".72c">because the lanikia supercluster is so</font>

200
00:07:49,520 --> 00:07:51,520
<font color="white" size=".72c">large</font>

201
00:07:50,159 --> 00:07:53,440
<font color="white" size=".72c">it is not dense enough to be</font>

202
00:07:51,520 --> 00:07:56,080
<font color="white" size=".72c">gravitationally bound</font>

203
00:07:53,440 --> 00:07:57,840
<font color="white" size=".72c">and so as the universe expands instead</font>

204
00:07:56,080 --> 00:07:58,560
<font color="white" size=".72c">of coming together and condensing</font>

205
00:07:57,840 --> 00:08:00,319
<font color="white" size=".72c">further</font>

206
00:07:58,560 --> 00:08:04,319
<font color="white" size=".72c">it should instead get caught up in the</font>

207
00:08:00,319 --> 00:08:06,800
<font color="white" size=".72c">hubble flow dispersing the supercluster</font>

208
00:08:04,319 --> 00:08:07,599
<font color="white" size=".72c">but that's not what we are observing in</font>

209
00:08:06,800 --> 00:08:09,280
<font color="white" size=".72c">practice</font>

210
00:08:07,599 --> 00:08:11,280
<font color="white" size=".72c">or at least not all of what we're</font>

211
00:08:09,280 --> 00:08:13,599
<font color="white" size=".72c">observing</font>

212
00:08:11,280 --> 00:08:15,360
<font color="white" size=".72c">in addition to the universe's expansion</font>

213
00:08:13,599 --> 00:08:18,000
<font color="white" size=".72c">elongating the structure</font>

214
00:08:15,360 --> 00:08:20,319
<font color="white" size=".72c">the entirety of the supercluster appears</font>

215
00:08:18,000 --> 00:08:20,800
<font color="white" size=".72c">to be being attracted to whatever is in</font>

216
00:08:20,319 --> 00:08:24,479
<font color="white" size=".72c">this</font>

217
00:08:20,800 --> 00:08:26,240
<font color="white" size=".72c">area the question is</font>

218
00:08:24,479 --> 00:08:27,840
<font color="white" size=".72c">what could possibly be there that is</font>

219
00:08:26,240 --> 00:08:31,840
<font color="white" size=".72c">powerful enough to unite</font>

220
00:08:27,840 --> 00:08:33,919
<font color="white" size=".72c">galactic superstructures of this size</font>

221
00:08:31,840 --> 00:08:35,279
<font color="white" size=".72c">flows of galaxies aren't uncommon within</font>

222
00:08:33,919 --> 00:08:38,320
<font color="white" size=".72c">galaxy wolves</font>

223
00:08:35,279 --> 00:08:40,479
<font color="white" size=".72c">but this is more than just the flow</font>

224
00:08:38,320 --> 00:08:42,000
<font color="white" size=".72c">there is a gravitational anomaly here</font>

225
00:08:40,479 --> 00:08:44,080
<font color="white" size=".72c">with enormous power</font>

226
00:08:42,000 --> 00:08:46,080
<font color="white" size=".72c">which is anchoring the entire cluster</font>

227
00:08:44,080 --> 00:08:48,160
<font color="white" size=".72c">together and making it move</font>

228
00:08:46,080 --> 00:08:50,399
<font color="white" size=".72c">like a sinkhole to a half a billion</font>

229
00:08:48,160 --> 00:08:52,959
<font color="white" size=".72c">light-year basin</font>

230
00:08:50,399 --> 00:08:55,839
<font color="white" size=".72c">this anomaly is what we mean when we say</font>

231
00:08:52,959 --> 00:08:55,839
<font color="white" size=".72c">the great attractor</font>

232
00:09:02,880 --> 00:09:07,120
<font color="white" size=".72c">the great attractor is the somewhat</font>

233
00:09:04,880 --> 00:09:08,000
<font color="white" size=".72c">ominous name given to the gravitational</font>

234
00:09:07,120 --> 00:09:10,640
<font color="white" size=".72c">focal point</font>

235
00:09:08,000 --> 00:09:11,920
<font color="white" size=".72c">of the lanikia supercluster thought to</font>

236
00:09:10,640 --> 00:09:14,160
<font color="white" size=".72c">lie somewhere around</font>

237
00:09:11,920 --> 00:09:15,760
<font color="white" size=".72c">250 million light years away from the</font>

238
00:09:14,160 --> 00:09:17,680
<font color="white" size=".72c">milky way</font>

239
00:09:15,760 --> 00:09:20,080
<font color="white" size=".72c">and it is attracting the contents of the</font>

240
00:09:17,680 --> 00:09:21,920
<font color="white" size=".72c">cluster towards it</font>

241
00:09:20,080 --> 00:09:23,680
<font color="white" size=".72c">everything for hundreds of millions of</font>

242
00:09:21,920 --> 00:09:26,080
<font color="white" size=".72c">light years is attracted to</font>

243
00:09:23,680 --> 00:09:28,480
<font color="white" size=".72c">and flowing towards this one region</font>

244
00:09:26,080 --> 00:09:30,480
<font color="white" size=".72c">which means one of two things</font>

245
00:09:28,480 --> 00:09:32,160
<font color="white" size=".72c">either there is an unusually high</font>

246
00:09:30,480 --> 00:09:34,240
<font color="white" size=".72c">concentration of mass there</font>

247
00:09:32,160 --> 00:09:35,360
<font color="white" size=".72c">like an ultramassive or dense galaxy</font>

248
00:09:34,240 --> 00:09:37,839
<font color="white" size=".72c">cluster</font>

249
00:09:35,360 --> 00:09:38,560
<font color="white" size=".72c">or perhaps something stranger like a</font>

250
00:09:37,839 --> 00:09:41,279
<font color="white" size=".72c">monstrous</font>

251
00:09:38,560 --> 00:09:43,360
<font color="white" size=".72c">intergalactic black hole or a mysterious</font>

252
00:09:41,279 --> 00:09:46,640
<font color="white" size=".72c">dark force which is counteracting the</font>

253
00:09:43,360 --> 00:09:48,560
<font color="white" size=".72c">universe's expansion</font>

254
00:09:46,640 --> 00:09:50,160
<font color="white" size=".72c">in reality it is likely to be the</font>

255
00:09:48,560 --> 00:09:52,560
<font color="white" size=".72c">product of a dense galaxy</font>

256
00:09:50,160 --> 00:09:54,720
<font color="white" size=".72c">supercluster so massive that it is</font>

257
00:09:52,560 --> 00:09:55,760
<font color="white" size=".72c">influencing the entirety of the virgo</font>

258
00:09:54,720 --> 00:09:58,640
<font color="white" size=".72c">supercluster</font>

259
00:09:55,760 --> 00:09:59,839
<font color="white" size=".72c">as well as the other clusters around it</font>

260
00:09:58,640 --> 00:10:02,800
<font color="white" size=".72c">but whatever it is</font>

261
00:09:59,839 --> 00:10:05,519
<font color="white" size=".72c">there is one fundamental issue we can't</font>

262
00:10:02,800 --> 00:10:07,600
<font color="white" size=".72c">see it</font>

263
00:10:05,519 --> 00:10:09,839
<font color="white" size=".72c">in addition to the nature of the source</font>

264
00:10:07,600 --> 00:10:11,440
<font color="white" size=".72c">itself one of the main things that makes</font>

265
00:10:09,839 --> 00:10:12,320
<font color="white" size=".72c">the greater tractor mystery so</font>

266
00:10:11,440 --> 00:10:16,720
<font color="white" size=".72c">intriguing</font>

267
00:10:12,320 --> 00:10:19,279
<font color="white" size=".72c">yet infuriating is its location</font>

268
00:10:16,720 --> 00:10:21,600
<font color="white" size=".72c">it lies in an area of the sky which is</font>

269
00:10:19,279 --> 00:10:23,200
<font color="white" size=".72c">blocked out by the milky way's galactic</font>

270
00:10:21,600 --> 00:10:25,519
<font color="white" size=".72c">plane from the point of view of the</font>

271
00:10:23,200 --> 00:10:27,440
<font color="white" size=".72c">earth</font>

272
00:10:25,519 --> 00:10:29,360
<font color="white" size=".72c">because of where the solar system lies</font>

273
00:10:27,440 --> 00:10:30,320
<font color="white" size=".72c">in relation to the milky way's galactic</font>

274
00:10:29,360 --> 00:10:32,640
<font color="white" size=".72c">plane</font>

275
00:10:30,320 --> 00:10:34,720
<font color="white" size=".72c">its bright illuminated core and dark</font>

276
00:10:32,640 --> 00:10:37,200
<font color="white" size=".72c">dusty clouds extinguish the light</font>

277
00:10:34,720 --> 00:10:39,279
<font color="white" size=".72c">reaching the galaxy from behind blocking</font>

278
00:10:37,200 --> 00:10:41,760
<font color="white" size=".72c">out approximately one-fifth of our field</font>

279
00:10:39,279 --> 00:10:41,760
<font color="white" size=".72c">of view</font>

280
00:10:41,920 --> 00:10:45,760
<font color="white" size=".72c">this area is known as the zone of</font>

281
00:10:44,079 --> 00:10:47,600
<font color="white" size=".72c">avoidance</font>

282
00:10:45,760 --> 00:10:49,839
<font color="white" size=".72c">where the galaxy's features make it</font>

283
00:10:47,600 --> 00:10:53,200
<font color="white" size=".72c">virtually impossible to see or detect</font>

284
00:10:49,839 --> 00:10:54,720
<font color="white" size=".72c">anything within or beyond it</font>

285
00:10:53,200 --> 00:10:57,120
<font color="white" size=".72c">there's nothing different about the</font>

286
00:10:54,720 --> 00:10:59,200
<font color="white" size=".72c">space behind the zone of avoidance</font>

287
00:10:57,120 --> 00:11:01,410
<font color="white" size=".72c">it is just our position relative to the</font>

288
00:10:59,200 --> 00:11:02,480
<font color="white" size=".72c">galactic core this is the problem</font>

289
00:11:01,410 --> 00:11:05,440
<font color="white" size=".72c">[Music]</font>

290
00:11:02,480 --> 00:11:07,519
<font color="white" size=".72c">in fact in about 100 million years or so</font>

291
00:11:05,440 --> 00:11:08,959
<font color="white" size=".72c">the sun will have orbited the galaxy's</font>

292
00:11:07,519 --> 00:11:10,800
<font color="white" size=".72c">central black hole</font>

293
00:11:08,959 --> 00:11:12,640
<font color="white" size=".72c">taking us to the other side of the milky</font>

294
00:11:10,800 --> 00:11:15,440
<font color="white" size=".72c">way where the backdrop of the zone of</font>

295
00:11:12,640 --> 00:11:17,279
<font color="white" size=".72c">avoidance will be revealed</font>

296
00:11:15,440 --> 00:11:19,440
<font color="white" size=".72c">but that's going to take a very very</font>

297
00:11:17,279 --> 00:11:20,320
<font color="white" size=".72c">long time and so for all intents and</font>

298
00:11:19,440 --> 00:11:23,600
<font color="white" size=".72c">purposes</font>

299
00:11:20,320 --> 00:11:25,519
<font color="white" size=".72c">we are stuck on this side and it just so</font>

300
00:11:23,600 --> 00:11:27,760
<font color="white" size=".72c">happens that the largest gravitational</font>

301
00:11:25,519 --> 00:11:29,279
<font color="white" size=".72c">anomaly in the local universe</font>

302
00:11:27,760 --> 00:11:30,800
<font color="white" size=".72c">which is dragging us and everything</font>

303
00:11:29,279 --> 00:11:32,880
<font color="white" size=".72c">around us towards it</font>

304
00:11:30,800 --> 00:11:34,160
<font color="white" size=".72c">happens to lie behind this obstructed</font>

305
00:11:32,880 --> 00:11:37,040
<font color="white" size=".72c">region</font>

306
00:11:34,160 --> 00:11:39,040
<font color="white" size=".72c">ironic right it certainly makes for a</font>

307
00:11:37,040 --> 00:11:41,360
<font color="white" size=".72c">genuinely interesting and somewhat</font>

308
00:11:39,040 --> 00:11:43,920
<font color="white" size=".72c">unnerving mystery in astronomy</font>

309
00:11:41,360 --> 00:11:46,240
<font color="white" size=".72c">which troubled scientists for around 40</font>

310
00:11:43,920 --> 00:11:46,240
<font color="white" size=".72c">years</font>

311
00:11:46,480 --> 00:11:51,120
<font color="white" size=".72c">the first signs of the greater tractor</font>

312
00:11:48,320 --> 00:11:53,200
<font color="white" size=".72c">were detected in the 1970s when we</font>

313
00:11:51,120 --> 00:11:55,200
<font color="white" size=".72c">realized that the milky way galaxy is</font>

314
00:11:53,200 --> 00:11:56,959
<font color="white" size=".72c">moving through space</font>

315
00:11:55,200 --> 00:11:58,720
<font color="white" size=".72c">back then there was no way to see or</font>

316
00:11:56,959 --> 00:12:00,160
<font color="white" size=".72c">detect anything behind the zone of</font>

317
00:11:58,720 --> 00:12:01,839
<font color="white" size=".72c">avoidance</font>

318
00:12:00,160 --> 00:12:04,000
<font color="white" size=".72c">they didn't have the sophisticated</font>

319
00:12:01,839 --> 00:12:05,279
<font color="white" size=".72c">technology that we have at our disposal</font>

320
00:12:04,000 --> 00:12:07,920
<font color="white" size=".72c">today</font>

321
00:12:05,279 --> 00:12:11,200
<font color="white" size=".72c">and so around 40 degrees of the sky</font>

322
00:12:07,920 --> 00:12:13,760
<font color="white" size=".72c">remained unmapped and unknowable</font>

323
00:12:11,200 --> 00:12:15,920
<font color="white" size=".72c">however as scientists began producing</font>

324
00:12:13,760 --> 00:12:17,600
<font color="white" size=".72c">the first detailed maps of the cosmic</font>

325
00:12:15,920 --> 00:12:19,440
<font color="white" size=".72c">microwave background</font>

326
00:12:17,600 --> 00:12:21,519
<font color="white" size=".72c">that is the primordial microwave</font>

327
00:12:19,440 --> 00:12:23,440
<font color="white" size=".72c">radiation left over from the big bang</font>

328
00:12:21,519 --> 00:12:25,920
<font color="white" size=".72c">which permeates all of space</font>

329
00:12:23,440 --> 00:12:27,519
<font color="white" size=".72c">they discovered what is known as the cmb</font>

330
00:12:25,920 --> 00:12:29,600
<font color="white" size=".72c">dipole</font>

331
00:12:27,519 --> 00:12:32,480
<font color="white" size=".72c">a gradient in the temperature of the sky</font>

332
00:12:29,600 --> 00:12:34,399
<font color="white" size=".72c">from one side to the other</font>

333
00:12:32,480 --> 00:12:36,800
<font color="white" size=".72c">scientists quickly realized that this</font>

334
00:12:34,399 --> 00:12:38,240
<font color="white" size=".72c">disparity is the result of the milky way</font>

335
00:12:36,800 --> 00:12:40,240
<font color="white" size=".72c">moving through space</font>

336
00:12:38,240 --> 00:12:42,639
<font color="white" size=".72c">and the motion in the direction of the</font>

337
00:12:40,240 --> 00:12:43,519
<font color="white" size=".72c">red area compresses the oncoming waves</font>

338
00:12:42,639 --> 00:12:46,320
<font color="white" size=".72c">of radiation</font>

339
00:12:43,519 --> 00:12:49,279
<font color="white" size=".72c">ever so slightly causing that direction</font>

340
00:12:46,320 --> 00:12:51,600
<font color="white" size=".72c">to appear slightly warmer</font>

341
00:12:49,279 --> 00:12:53,120
<font color="white" size=".72c">as we know galaxy's moving through space</font>

342
00:12:51,600 --> 00:12:55,920
<font color="white" size=".72c">is not that unusual</font>

343
00:12:53,120 --> 00:12:58,560
<font color="white" size=".72c">as all galaxies are moving apart largely</font>

344
00:12:55,920 --> 00:13:01,360
<font color="white" size=".72c">in accordance with the hubble flow</font>

345
00:12:58,560 --> 00:13:02,160
<font color="white" size=".72c">but things can affect this flow namely</font>

346
00:13:01,360 --> 00:13:04,839
<font color="white" size=".72c">gravity</font>

347
00:13:02,160 --> 00:13:06,079
<font color="white" size=".72c">and the gravity of objects around a</font>

348
00:13:04,839 --> 00:13:08,079
<font color="white" size=".72c">galaxy</font>

349
00:13:06,079 --> 00:13:09,600
<font color="white" size=".72c">the discrepancy between a galaxy's</font>

350
00:13:08,079 --> 00:13:11,600
<font color="white" size=".72c">actual movement through space</font>

351
00:13:09,600 --> 00:13:13,519
<font color="white" size=".72c">due to gravity when compared with what</font>

352
00:13:11,600 --> 00:13:15,519
<font color="white" size=".72c">one would expect in an expanding</font>

353
00:13:13,519 --> 00:13:16,800
<font color="white" size=".72c">universe is known as its peculiar</font>

354
00:13:15,519 --> 00:13:18,959
<font color="white" size=".72c">velocity</font>

355
00:13:16,800 --> 00:13:20,079
<font color="white" size=".72c">in layman's terms the speed at which a</font>

356
00:13:18,959 --> 00:13:21,839
<font color="white" size=".72c">galaxy moves through</font>

357
00:13:20,079 --> 00:13:24,800
<font color="white" size=".72c">space because of something other than</font>

358
00:13:21,839 --> 00:13:26,639
<font color="white" size=".72c">the universe's expansion</font>

359
00:13:24,800 --> 00:13:29,040
<font color="white" size=".72c">when we tried to measure our peculiar</font>

360
00:13:26,639 --> 00:13:30,320
<font color="white" size=".72c">velocity by tracking the sun relative to</font>

361
00:13:29,040 --> 00:13:32,320
<font color="white" size=".72c">the cmb</font>

362
00:13:30,320 --> 00:13:34,399
<font color="white" size=".72c">we discovered that we are moving towards</font>

363
00:13:32,320 --> 00:13:37,920
<font color="white" size=".72c">the constellation of centaurus at a</font>

364
00:13:34,399 --> 00:13:40,720
<font color="white" size=".72c">speed of about 600 kilometers per second</font>

365
00:13:37,920 --> 00:13:43,360
<font color="white" size=".72c">and this isn't by chance either</font>

366
00:13:40,720 --> 00:13:45,279
<font color="white" size=".72c">something in that area is attracting us</font>

367
00:13:43,360 --> 00:13:48,079
<font color="white" size=".72c">but wherever we were headed it was</font>

368
00:13:45,279 --> 00:13:49,839
<font color="white" size=".72c">situated behind the zone of avoidance</font>

369
00:13:48,079 --> 00:13:51,920
<font color="white" size=".72c">and so the cause of this peculiar</font>

370
00:13:49,839 --> 00:13:56,240
<font color="white" size=".72c">velocity remained a topic of fierce</font>

371
00:13:51,920 --> 00:13:56,240
<font color="white" size=".72c">debate and speculation for many years</font>

372
00:13:58,800 --> 00:14:02,320
<font color="white" size=".72c">initial hypotheses were that they were</font>

373
00:14:00,639 --> 00:14:03,839
<font color="white" size=".72c">just simply more galaxies</font>

374
00:14:02,320 --> 00:14:06,560
<font color="white" size=".72c">in the direction of the zone of</font>

375
00:14:03,839 --> 00:14:08,639
<font color="white" size=".72c">avoidance which we just couldn't see</font>

376
00:14:06,560 --> 00:14:11,040
<font color="white" size=".72c">the milky way's outlying position to the</font>

377
00:14:08,639 --> 00:14:14,079
<font color="white" size=".72c">much denser virgo cluster was also</font>

378
00:14:11,040 --> 00:14:16,320
<font color="white" size=".72c">attributed as a possible cause</font>

379
00:14:14,079 --> 00:14:18,000
<font color="white" size=".72c">however while the virgo cluster could</font>

380
00:14:16,320 --> 00:14:19,839
<font color="white" size=".72c">attract us with its gravity</font>

381
00:14:18,000 --> 00:14:22,800
<font color="white" size=".72c">it is not nearly massive enough to</font>

382
00:14:19,839 --> 00:14:24,959
<font color="white" size=".72c">explain the speed at which we are moving</font>

383
00:14:22,800 --> 00:14:26,639
<font color="white" size=".72c">something considerably more massive was</font>

384
00:14:24,959 --> 00:14:29,120
<font color="white" size=".72c">to blame</font>

385
00:14:26,639 --> 00:14:31,600
<font color="white" size=".72c">and then the mystery got even bigger</font>

386
00:14:29,120 --> 00:14:33,760
<font color="white" size=".72c">quite literally</font>

387
00:14:31,600 --> 00:14:35,120
<font color="white" size=".72c">as redshift surveys began mapping the</font>

388
00:14:33,760 --> 00:14:38,240
<font color="white" size=".72c">universe in 3d</font>

389
00:14:35,120 --> 00:14:40,000
<font color="white" size=".72c">during the 1980s we realized that not</font>

390
00:14:38,240 --> 00:14:42,480
<font color="white" size=".72c">only are we moving towards this</font>

391
00:14:40,000 --> 00:14:44,639
<font color="white" size=".72c">gravitational anomaly in centaurus</font>

392
00:14:42,480 --> 00:14:47,360
<font color="white" size=".72c">but so are the galaxies both above and</font>

393
00:14:44,639 --> 00:14:49,600
<font color="white" size=".72c">below the zone of avoidance</font>

394
00:14:47,360 --> 00:14:52,160
<font color="white" size=".72c">the power of the source was much greater</font>

395
00:14:49,600 --> 00:14:55,360
<font color="white" size=".72c">than once thought</font>

396
00:14:52,160 --> 00:14:58,160
<font color="white" size=".72c">in 1986 it was estimated that the source</font>

397
00:14:55,360 --> 00:15:01,199
<font color="white" size=".72c">of this anomaly lies between 150 million</font>

398
00:14:58,160 --> 00:15:03,440
<font color="white" size=".72c">and 220 million light years away</font>

399
00:15:01,199 --> 00:15:04,720
<font color="white" size=".72c">and two years later an international</font>

400
00:15:03,440 --> 00:15:07,360
<font color="white" size=".72c">team of researchers</font>

401
00:15:04,720 --> 00:15:10,079
<font color="white" size=".72c">led by donald lyndon bell proposed that</font>

402
00:15:07,360 --> 00:15:10,800
<font color="white" size=".72c">the observed motions of 400 elliptical</font>

403
00:15:10,079 --> 00:15:13,120
<font color="white" size=".72c">galaxies</font>

404
00:15:10,800 --> 00:15:15,360
<font color="white" size=".72c">were best fitted by a large bulk flow of</font>

405
00:15:13,120 --> 00:15:17,600
<font color="white" size=".72c">galaxies towards a so-called great</font>

406
00:15:15,360 --> 00:15:19,199
<font color="white" size=".72c">attractor lurking behind the zone of</font>

407
00:15:17,600 --> 00:15:22,880
<font color="white" size=".72c">avoidance</font>

408
00:15:19,199 --> 00:15:24,480
<font color="white" size=".72c">and thus the term was coined</font>

409
00:15:22,880 --> 00:15:27,120
<font color="white" size=".72c">while we didn't know what was causing</font>

410
00:15:24,480 --> 00:15:28,800
<font color="white" size=".72c">the great attractor in order to explain</font>

411
00:15:27,120 --> 00:15:30,320
<font color="white" size=".72c">our peculiar velocity</font>

412
00:15:28,800 --> 00:15:31,920
<font color="white" size=".72c">as well as the motions of so many</font>

413
00:15:30,320 --> 00:15:33,680
<font color="white" size=".72c">galaxies around us</font>

414
00:15:31,920 --> 00:15:36,160
<font color="white" size=".72c">the source of the great attractor was</font>

415
00:15:33,680 --> 00:15:38,160
<font color="white" size=".72c">predicted to be around 10 quintillion</font>

416
00:15:36,160 --> 00:15:41,279
<font color="white" size=".72c">times the mass of the sun</font>

417
00:15:38,160 --> 00:15:43,519
<font color="white" size=".72c">that's 10 million billion suns</font>

418
00:15:41,279 --> 00:15:44,880
<font color="white" size=".72c">equivalent to many thousands of massive</font>

419
00:15:43,519 --> 00:15:46,959
<font color="white" size=".72c">galaxies</font>

420
00:15:44,880 --> 00:15:49,440
<font color="white" size=".72c">and so naturally astronomers were keen</font>

421
00:15:46,959 --> 00:15:51,000
<font color="white" size=".72c">to establish exactly what was lurking in</font>

422
00:15:49,440 --> 00:15:52,959
<font color="white" size=".72c">the dark</font>

423
00:15:51,000 --> 00:15:55,199
<font color="white" size=".72c">[Music]</font>

424
00:15:52,959 --> 00:15:57,040
<font color="white" size=".72c">back when it was first noted our search</font>

425
00:15:55,199 --> 00:15:59,440
<font color="white" size=".72c">for the greater tractor was severely</font>

426
00:15:57,040 --> 00:16:01,519
<font color="white" size=".72c">hindered by the zone of avoidance</font>

427
00:15:59,440 --> 00:16:04,000
<font color="white" size=".72c">but times have changed and technology</font>

428
00:16:01,519 --> 00:16:06,000
<font color="white" size=".72c">has vastly improved</font>

429
00:16:04,000 --> 00:16:08,959
<font color="white" size=".72c">for one thing we're not simply limited</font>

430
00:16:06,000 --> 00:16:10,560
<font color="white" size=".72c">to observing visible light anymore</font>

431
00:16:08,959 --> 00:16:13,040
<font color="white" size=".72c">while the milky way's plane might be</font>

432
00:16:10,560 --> 00:16:15,440
<font color="white" size=".72c">opaque to light that we can see</font>

433
00:16:13,040 --> 00:16:17,680
<font color="white" size=".72c">radio and infrared emissions from galaxy</font>

434
00:16:15,440 --> 00:16:19,920
<font color="white" size=".72c">superclusters outside of the milky way</font>

435
00:16:17,680 --> 00:16:20,800
<font color="white" size=".72c">are capable of penetrating the galaxy's</font>

436
00:16:19,920 --> 00:16:24,000
<font color="white" size=".72c">clouds</font>

437
00:16:20,800 --> 00:16:25,600
<font color="white" size=".72c">even if only slightly this gives us some</font>

438
00:16:24,000 --> 00:16:28,240
<font color="white" size=".72c">idea of what could lie beyond</font>

439
00:16:25,600 --> 00:16:30,000
<font color="white" size=".72c">the avoidance zone albeit a very limited</font>

440
00:16:28,240 --> 00:16:32,320
<font color="white" size=".72c">picture</font>

441
00:16:30,000 --> 00:16:33,839
<font color="white" size=".72c">instead the best means we have of seeing</font>

442
00:16:32,320 --> 00:16:37,519
<font color="white" size=".72c">behind the zone of avoidance</font>

443
00:16:33,839 --> 00:16:39,920
<font color="white" size=".72c">is through x-rays x-rays are another</font>

444
00:16:37,519 --> 00:16:43,279
<font color="white" size=".72c">kind of electromagnetic radiation</font>

445
00:16:39,920 --> 00:16:45,920
<font color="white" size=".72c">like visible light radio and infrared</font>

446
00:16:43,279 --> 00:16:48,079
<font color="white" size=".72c">like the latter x-rays can also pass</font>

447
00:16:45,920 --> 00:16:51,680
<font color="white" size=".72c">through the opaque galactic plane</font>

448
00:16:48,079 --> 00:16:54,079
<font color="white" size=".72c">and are emitted by galaxy superclusters</font>

449
00:16:51,680 --> 00:16:56,320
<font color="white" size=".72c">in addition there are far fewer x-ray</font>

450
00:16:54,079 --> 00:16:58,880
<font color="white" size=".72c">emitting sources in space than there are</font>

451
00:16:56,320 --> 00:17:00,959
<font color="white" size=".72c">sources of infrared and radio waves</font>

452
00:16:58,880 --> 00:17:03,839
<font color="white" size=".72c">making supercluster x-ray emitters</font>

453
00:17:00,959 --> 00:17:07,359
<font color="white" size=".72c">easier to identify</font>

454
00:17:03,839 --> 00:17:08,720
<font color="white" size=".72c">in 1996 using data from the rosat</font>

455
00:17:07,359 --> 00:17:11,119
<font color="white" size=".72c">microwave mission</font>

456
00:17:08,720 --> 00:17:13,599
<font color="white" size=".72c">a team of researchers led by south</font>

457
00:17:11,119 --> 00:17:14,559
<font color="white" size=".72c">african astrophysicist renee krohn</font>

458
00:17:13,599 --> 00:17:16,319
<font color="white" size=".72c">cortez</font>

459
00:17:14,559 --> 00:17:17,919
<font color="white" size=".72c">discovered evidence for a galaxy</font>

460
00:17:16,319 --> 00:17:20,079
<font color="white" size=".72c">supercluster within the zone of</font>

461
00:17:17,919 --> 00:17:21,439
<font color="white" size=".72c">avoidance that had previously evaded</font>

462
00:17:20,079 --> 00:17:23,119
<font color="white" size=".72c">detection</font>

463
00:17:21,439 --> 00:17:25,199
<font color="white" size=".72c">now thought to be a key galactic</font>

464
00:17:23,119 --> 00:17:27,280
<font color="white" size=".72c">concentration at the heart of the great</font>

465
00:17:25,199 --> 00:17:29,280
<font color="white" size=".72c">attractor</font>

466
00:17:27,280 --> 00:17:30,880
<font color="white" size=".72c">while the cluster had been undetectable</font>

467
00:17:29,280 --> 00:17:32,720
<font color="white" size=".72c">through visible light within an</font>

468
00:17:30,880 --> 00:17:35,600
<font color="white" size=".72c">area spanning just two degrees of the</font>

469
00:17:32,720 --> 00:17:38,240
<font color="white" size=".72c">sky by plotting the x-ray sources</font>

470
00:17:35,600 --> 00:17:40,720
<font color="white" size=".72c">identified by rosat onto the area</font>

471
00:17:38,240 --> 00:17:42,160
<font color="white" size=".72c">a significant galaxy cluster is revealed</font>

472
00:17:40,720 --> 00:17:46,240
<font color="white" size=".72c">in the backdrop</font>

473
00:17:42,160 --> 00:17:48,640
<font color="white" size=".72c">known as arbul 3627 also known as the</font>

474
00:17:46,240 --> 00:17:51,600
<font color="white" size=".72c">norma cluster</font>

475
00:17:48,640 --> 00:17:53,679
<font color="white" size=".72c">the norma cluster lies around 220</font>

476
00:17:51,600 --> 00:17:55,440
<font color="white" size=".72c">million light years away from the earth</font>

477
00:17:53,679 --> 00:17:58,559
<font color="white" size=".72c">and is thought to be very close to the</font>

478
00:17:55,440 --> 00:18:00,400
<font color="white" size=".72c">proposed heart of the greater tractor</font>

479
00:17:58,559 --> 00:18:02,880
<font color="white" size=".72c">and it is thought to have a mass in the</font>

480
00:18:00,400 --> 00:18:04,480
<font color="white" size=".72c">region of one quadrillion times that of</font>

481
00:18:02,880 --> 00:18:06,480
<font color="white" size=".72c">our sun</font>

482
00:18:04,480 --> 00:18:08,799
<font color="white" size=".72c">and so we realized that the great</font>

483
00:18:06,480 --> 00:18:09,120
<font color="white" size=".72c">attractor was probably a supercluster</font>

484
00:18:08,799 --> 00:18:11,550
<font color="white" size=".72c">with</font>

485
00:18:09,120 --> 00:18:12,960
<font color="white" size=".72c">arbol 3627 near its core</font>

486
00:18:11,550 --> 00:18:15,280
<font color="white" size=".72c">[Music]</font>

487
00:18:12,960 --> 00:18:17,360
<font color="white" size=".72c">however even at the time the team knew</font>

488
00:18:15,280 --> 00:18:19,760
<font color="white" size=".72c">that the norma cluster probably didn't</font>

489
00:18:17,360 --> 00:18:21,840
<font color="white" size=".72c">account for the full picture</font>

490
00:18:19,760 --> 00:18:23,360
<font color="white" size=".72c">while it is massive it didn't seem</font>

491
00:18:21,840 --> 00:18:26,320
<font color="white" size=".72c">massive enough to account for the</font>

492
00:18:23,360 --> 00:18:28,960
<font color="white" size=".72c">peculiar velocity of the milky way</font>

493
00:18:26,320 --> 00:18:30,960
<font color="white" size=".72c">something else must be at work but</font>

494
00:18:28,960 --> 00:18:32,320
<font color="white" size=".72c">unfortunately we were still limited in</font>

495
00:18:30,960 --> 00:18:33,840
<font color="white" size=".72c">what we could observe due to the</font>

496
00:18:32,320 --> 00:18:36,480
<font color="white" size=".72c">obscured zone</font>

497
00:18:33,840 --> 00:18:39,919
<font color="white" size=".72c">and so the mystery remained inconclusive</font>

498
00:18:36,480 --> 00:18:39,919
<font color="white" size=".72c">heading into the new millennium</font>

499
00:18:41,120 --> 00:18:44,240
<font color="white" size=".72c">while many scientists agree that the</font>

500
00:18:43,200 --> 00:18:46,000
<font color="white" size=".72c">great attractor</font>

501
00:18:44,240 --> 00:18:47,280
<font color="white" size=".72c">is the result of a dense galaxy</font>

502
00:18:46,000 --> 00:18:49,039
<font color="white" size=".72c">concentration</font>

503
00:18:47,280 --> 00:18:51,280
<font color="white" size=".72c">i should take this opportunity to</font>

504
00:18:49,039 --> 00:18:53,440
<font color="white" size=".72c">mention that it is by no means the only</font>

505
00:18:51,280 --> 00:18:55,520
<font color="white" size=".72c">theory</font>

506
00:18:53,440 --> 00:18:58,160
<font color="white" size=".72c">there were those who refuted the idea of</font>

507
00:18:55,520 --> 00:19:00,160
<font color="white" size=".72c">a galaxy supercluster being responsible</font>

508
00:18:58,160 --> 00:19:01,840
<font color="white" size=".72c">due to the incomparable scale of its</font>

509
00:19:00,160 --> 00:19:04,320
<font color="white" size=".72c">influence when compared with other</font>

510
00:19:01,840 --> 00:19:07,280
<font color="white" size=".72c">cosmic structures</font>

511
00:19:04,320 --> 00:19:09,520
<font color="white" size=".72c">in fact because the universe's expansion</font>

512
00:19:07,280 --> 00:19:12,240
<font color="white" size=".72c">is thought to be powered and accelerated</font>

513
00:19:09,520 --> 00:19:14,160
<font color="white" size=".72c">by a phenomenon known as dark energy</font>

514
00:19:12,240 --> 00:19:15,600
<font color="white" size=".72c">there are those who suggest that only</font>

515
00:19:14,160 --> 00:19:18,799
<font color="white" size=".72c">something equally as</font>

516
00:19:15,600 --> 00:19:21,280
<font color="white" size=".72c">dark would be sufficient to overcome it</font>

517
00:19:18,799 --> 00:19:24,320
<font color="white" size=".72c">dark in the sense that it is unknown and</font>

518
00:19:21,280 --> 00:19:26,080
<font color="white" size=".72c">beyond our realm of understanding</font>

519
00:19:24,320 --> 00:19:28,160
<font color="white" size=".72c">this brings us onto a branch of</font>

520
00:19:26,080 --> 00:19:29,520
<font color="white" size=".72c">alternate explanations for the great</font>

521
00:19:28,160 --> 00:19:31,440
<font color="white" size=".72c">attractor</font>

522
00:19:29,520 --> 00:19:33,440
<font color="white" size=".72c">the idea that instead of a galaxy</font>

523
00:19:31,440 --> 00:19:35,760
<font color="white" size=".72c">supercluster attracting us</font>

524
00:19:33,440 --> 00:19:37,440
<font color="white" size=".72c">a mysterious undiscovered force is</font>

525
00:19:35,760 --> 00:19:38,720
<font color="white" size=".72c">responsible for the bulk flows of</font>

526
00:19:37,440 --> 00:19:41,760
<font color="white" size=".72c">galaxies that we see</font>

527
00:19:38,720 --> 00:19:45,520
<font color="white" size=".72c">in lanikia like enormous jet stream air</font>

528
00:19:41,760 --> 00:19:48,720
<font color="white" size=".72c">currents in the vacuum of space</font>

529
00:19:45,520 --> 00:19:51,200
<font color="white" size=".72c">this idea is called dark flow and it is</font>

530
00:19:48,720 --> 00:19:53,120
<font color="white" size=".72c">defined as a non-random component</font>

531
00:19:51,200 --> 00:19:55,200
<font color="white" size=".72c">of the universe's expansion which</font>

532
00:19:53,120 --> 00:19:57,440
<font color="white" size=".72c">deviates from the hubble flow</font>

533
00:19:55,200 --> 00:19:58,320
<font color="white" size=".72c">causing galaxies to stream towards a</font>

534
00:19:57,440 --> 00:20:00,400
<font color="white" size=".72c">single point</font>

535
00:19:58,320 --> 00:20:02,400
<font color="white" size=".72c">like the greater tractor rather than</font>

536
00:20:00,400 --> 00:20:05,039
<font color="white" size=".72c">receding away from one another as one</font>

537
00:20:02,400 --> 00:20:06,799
<font color="white" size=".72c">might expect</font>

538
00:20:05,039 --> 00:20:08,720
<font color="white" size=".72c">if this is the case and there is</font>

539
00:20:06,799 --> 00:20:09,679
<font color="white" size=".72c">something darker at play than we yet</font>

540
00:20:08,720 --> 00:20:11,440
<font color="white" size=".72c">realize</font>

541
00:20:09,679 --> 00:20:14,000
<font color="white" size=".72c">then perhaps we might be able to see</font>

542
00:20:11,440 --> 00:20:15,200
<font color="white" size=".72c">evidence of a gigantic flow mechanism by</font>

543
00:20:14,000 --> 00:20:16,880
<font color="white" size=".72c">searching for something</font>

544
00:20:15,200 --> 00:20:19,440
<font color="white" size=".72c">at the opposite end of the great</font>

545
00:20:16,880 --> 00:20:22,159
<font color="white" size=".72c">attractor a great repeller</font>

546
00:20:19,440 --> 00:20:23,280
<font color="white" size=".72c">if you would while that might sound a</font>

547
00:20:22,159 --> 00:20:26,799
<font color="white" size=".72c">bit outlandish</font>

548
00:20:23,280 --> 00:20:27,919
<font color="white" size=".72c">in 2017 we did see something just like</font>

549
00:20:26,799 --> 00:20:32,240
<font color="white" size=".72c">this</font>

550
00:20:27,919 --> 00:20:34,080
<font color="white" size=".72c">the dipole repeller just as all galaxies</font>

551
00:20:32,240 --> 00:20:36,240
<font color="white" size=".72c">in the lanikia supercluster</font>

552
00:20:34,080 --> 00:20:38,480
<font color="white" size=".72c">are flowing towards the great attractor</font>

553
00:20:36,240 --> 00:20:40,240
<font color="white" size=".72c">they all seem to be flowing away from an</font>

554
00:20:38,480 --> 00:20:41,600
<font color="white" size=".72c">area on the opposite end of the</font>

555
00:20:40,240 --> 00:20:43,520
<font color="white" size=".72c">supercluster</font>

556
00:20:41,600 --> 00:20:45,679
<font color="white" size=".72c">a region which appears to be pushing its</font>

557
00:20:43,520 --> 00:20:47,679
<font color="white" size=".72c">galaxies outwards and setting them on</font>

558
00:20:45,679 --> 00:20:49,520
<font color="white" size=".72c">their galactic paths towards the greater</font>

559
00:20:47,679 --> 00:20:51,360
<font color="white" size=".72c">tractor</font>

560
00:20:49,520 --> 00:20:53,440
<font color="white" size=".72c">perhaps the greater tractor and the</font>

561
00:20:51,360 --> 00:20:54,480
<font color="white" size=".72c">dipole repeller are part of some dark</font>

562
00:20:53,440 --> 00:20:56,640
<font color="white" size=".72c">cosmic system</font>

563
00:20:54,480 --> 00:20:59,600
<font color="white" size=".72c">capable of overcoming the effects of the</font>

564
00:20:56,640 --> 00:21:02,000
<font color="white" size=".72c">universe's expansion</font>

565
00:20:59,600 --> 00:21:04,000
<font color="white" size=".72c">however while the dipole repeller may</font>

566
00:21:02,000 --> 00:21:05,600
<font color="white" size=".72c">seem anomalous and indicative of</font>

567
00:21:04,000 --> 00:21:07,520
<font color="white" size=".72c">something more spooky</font>

568
00:21:05,600 --> 00:21:10,080
<font color="white" size=".72c">dark flow certainly doesn't need to</font>

569
00:21:07,520 --> 00:21:12,480
<font color="white" size=".72c">exist to explain it</font>

570
00:21:10,080 --> 00:21:14,080
<font color="white" size=".72c">in fact the dipole repeller probably</font>

571
00:21:12,480 --> 00:21:16,720
<font color="white" size=".72c">isn't even an anomaly</font>

572
00:21:14,080 --> 00:21:19,200
<font color="white" size=".72c">but rather a natural byproduct of galaxy</font>

573
00:21:16,720 --> 00:21:21,360
<font color="white" size=".72c">cluster formation</font>

574
00:21:19,200 --> 00:21:23,280
<font color="white" size=".72c">as the compound process of galaxies</font>

575
00:21:21,360 --> 00:21:25,440
<font color="white" size=".72c">gathering and attracting more galaxies</font>

576
00:21:23,280 --> 00:21:27,440
<font color="white" size=".72c">creates denser galaxy clusters</font>

577
00:21:25,440 --> 00:21:29,200
<font color="white" size=".72c">this process in turn empties out the</font>

578
00:21:27,440 --> 00:21:31,200
<font color="white" size=".72c">space around the cluster</font>

579
00:21:29,200 --> 00:21:33,280
<font color="white" size=".72c">creating voids between clumps of</font>

580
00:21:31,200 --> 00:21:35,440
<font color="white" size=".72c">galaxies</font>

581
00:21:33,280 --> 00:21:37,760
<font color="white" size=".72c">the more populous and massive the galaxy</font>

582
00:21:35,440 --> 00:21:38,400
<font color="white" size=".72c">cluster the more voids will form around</font>

583
00:21:37,760 --> 00:21:40,720
<font color="white" size=".72c">it</font>

584
00:21:38,400 --> 00:21:43,520
<font color="white" size=".72c">as areas are raided for their galaxies</font>

585
00:21:40,720 --> 00:21:45,760
<font color="white" size=".72c">to feed the structure</font>

586
00:21:43,520 --> 00:21:47,600
<font color="white" size=".72c">and so while it may seem like galaxies</font>

587
00:21:45,760 --> 00:21:48,559
<font color="white" size=".72c">are being pushed away from the dipole</font>

588
00:21:47,600 --> 00:21:51,360
<font color="white" size=".72c">repeller</font>

589
00:21:48,559 --> 00:21:53,760
<font color="white" size=".72c">in reality nothing is pushing them only</font>

590
00:21:51,360 --> 00:21:55,840
<font color="white" size=".72c">the pulling force of gravity</font>

591
00:21:53,760 --> 00:21:57,600
<font color="white" size=".72c">and the dipole repeller is merely just</font>

592
00:21:55,840 --> 00:21:58,960
<font color="white" size=".72c">an area which has had its galaxies</font>

593
00:21:57,600 --> 00:22:01,600
<font color="white" size=".72c">emptied out by massive</font>

594
00:21:58,960 --> 00:22:05,280
<font color="white" size=".72c">influences which holds the appearance of</font>

595
00:22:01,600 --> 00:22:05,280
<font color="white" size=".72c">a so-called virtual repeller</font>

596
00:22:05,440 --> 00:22:09,360
<font color="white" size=".72c">so then if there is no dark force at</font>

597
00:22:07,440 --> 00:22:12,000
<font color="white" size=".72c">work to produce these flows</font>

598
00:22:09,360 --> 00:22:14,080
<font color="white" size=".72c">then what is causing us to move so fast</font>

599
00:22:12,000 --> 00:22:16,960
<font color="white" size=".72c">if not the clusters in the region of the</font>

600
00:22:14,080 --> 00:22:16,960
<font color="white" size=".72c">greater tractor</font>

601
00:22:17,600 --> 00:22:22,000
<font color="white" size=".72c">in the early 2000s a study called the</font>

602
00:22:20,159 --> 00:22:22,880
<font color="white" size=".72c">clusters in the zone of avoidance</font>

603
00:22:22,000 --> 00:22:25,840
<font color="white" size=".72c">project</font>

604
00:22:22,880 --> 00:22:27,919
<font color="white" size=".72c">or caesar selected x-ray signatures</font>

605
00:22:25,840 --> 00:22:29,520
<font color="white" size=".72c">recorded by the rosat mission for</font>

606
00:22:27,919 --> 00:22:31,600
<font color="white" size=".72c">follow-up and investigation</font>

607
00:22:29,520 --> 00:22:34,000
<font color="white" size=".72c">with newer more effective x-ray</font>

608
00:22:31,600 --> 00:22:36,080
<font color="white" size=".72c">technology</font>

609
00:22:34,000 --> 00:22:37,760
<font color="white" size=".72c">the aim of the project was to map this</font>

610
00:22:36,080 --> 00:22:39,679
<font color="white" size=".72c">final portion of the sky</font>

611
00:22:37,760 --> 00:22:41,760
<font color="white" size=".72c">in the zone of avoidance that remained</font>

612
00:22:39,679 --> 00:22:44,000
<font color="white" size=".72c">uncharted for so many years</font>

613
00:22:41,760 --> 00:22:46,159
<font color="white" size=".72c">and also to focus in on what makes the</font>

614
00:22:44,000 --> 00:22:49,760
<font color="white" size=".72c">region of the great attractor so</font>

615
00:22:46,159 --> 00:22:52,559
<font color="white" size=".72c">great in doing so</font>

616
00:22:49,760 --> 00:22:54,960
<font color="white" size=".72c">they identified over 200 previously</font>

617
00:22:52,559 --> 00:22:56,320
<font color="white" size=".72c">undiscovered galaxy clusters in galactic</font>

618
00:22:54,960 --> 00:22:58,320
<font color="white" size=".72c">no-man's land</font>

619
00:22:56,320 --> 00:23:00,720
<font color="white" size=".72c">including in the proposed region of the</font>

620
00:22:58,320 --> 00:23:03,360
<font color="white" size=".72c">great attractor</font>

621
00:23:00,720 --> 00:23:05,440
<font color="white" size=".72c">however these clusters were found to be</font>

622
00:23:03,360 --> 00:23:07,200
<font color="white" size=".72c">significantly less massive than what was</font>

623
00:23:05,440 --> 00:23:08,960
<font color="white" size=".72c">once predicted to account for our</font>

624
00:23:07,200 --> 00:23:11,120
<font color="white" size=".72c">peculiar velocity</font>

625
00:23:08,960 --> 00:23:12,720
<font color="white" size=".72c">only a tenth of the proposed mass in</font>

626
00:23:11,120 --> 00:23:15,200
<font color="white" size=".72c">fact</font>

627
00:23:12,720 --> 00:23:18,320
<font color="white" size=".72c">in reality the great attractor is not</font>

628
00:23:15,200 --> 00:23:20,000
<font color="white" size=".72c">nearly as great as we once thought</font>

629
00:23:18,320 --> 00:23:22,159
<font color="white" size=".72c">while it is the focal point of the</font>

630
00:23:20,000 --> 00:23:23,440
<font color="white" size=".72c">lanikia supercluster which is dragging</font>

631
00:23:22,159 --> 00:23:27,280
<font color="white" size=".72c">us towards it</font>

632
00:23:23,440 --> 00:23:29,919
<font color="white" size=".72c">it is not the only thing influencing us</font>

633
00:23:27,280 --> 00:23:32,240
<font color="white" size=".72c">instead the caesar survey revealed a</font>

634
00:23:29,919 --> 00:23:34,559
<font color="white" size=".72c">substantial concentration of galaxies</font>

635
00:23:32,240 --> 00:23:38,320
<font color="white" size=".72c">much further beyond the greater tractor</font>

636
00:23:34,559 --> 00:23:38,320
<font color="white" size=".72c">near the shapley supercluster</font>

637
00:23:42,159 --> 00:23:46,000
<font color="white" size=".72c">the shapley supercluster is one of the</font>

638
00:23:44,159 --> 00:23:49,120
<font color="white" size=".72c">most studied of its kind</font>

639
00:23:46,000 --> 00:23:50,000
<font color="white" size=".72c">with its 25 constituent galaxy clusters</font>

640
00:23:49,120 --> 00:23:55,200
<font color="white" size=".72c">marked here in</font>

641
00:23:50,000 --> 00:23:57,200
<font color="white" size=".72c">blue it is situated around 650 million</font>

642
00:23:55,200 --> 00:23:59,679
<font color="white" size=".72c">light years away from the milky way</font>

643
00:23:57,200 --> 00:24:01,279
<font color="white" size=".72c">and while it was discovered in the 1930s</font>

644
00:23:59,679 --> 00:24:03,039
<font color="white" size=".72c">by harlow shapley</font>

645
00:24:01,279 --> 00:24:05,360
<font color="white" size=".72c">it didn't become a topic of interest</font>

646
00:24:03,039 --> 00:24:07,600
<font color="white" size=".72c">until the late 90s and the advent of</font>

647
00:24:05,360 --> 00:24:11,039
<font color="white" size=".72c">better technology</font>

648
00:24:07,600 --> 00:24:13,760
<font color="white" size=".72c">but from 1997 until 2001</font>

649
00:24:11,039 --> 00:24:15,600
<font color="white" size=".72c">no less than 40 scientific papers were</font>

650
00:24:13,760 --> 00:24:18,640
<font color="white" size=".72c">published on the cluster</font>

651
00:24:15,600 --> 00:24:20,799
<font color="white" size=".72c">and in 2005 caesar discovered a</font>

652
00:24:18,640 --> 00:24:23,600
<font color="white" size=".72c">concentrated region of galaxies in the</font>

653
00:24:20,799 --> 00:24:26,880
<font color="white" size=".72c">vicinity of the shapley supercluster</font>

654
00:24:23,600 --> 00:24:29,200
<font color="white" size=".72c">nicknamed the shapley attractor</font>

655
00:24:26,880 --> 00:24:32,320
<font color="white" size=".72c">an even greater a more massive galactic</font>

656
00:24:29,200 --> 00:24:34,400
<font color="white" size=".72c">over density than the great attractor</font>

657
00:24:32,320 --> 00:24:36,640
<font color="white" size=".72c">lying around half a billion light years</font>

658
00:24:34,400 --> 00:24:39,279
<font color="white" size=".72c">away</font>

659
00:24:36,640 --> 00:24:40,799
<font color="white" size=".72c">in total shapley is home to more than 8</font>

660
00:24:39,279 --> 00:24:42,960
<font color="white" size=".72c">000 galaxies</font>

661
00:24:40,799 --> 00:24:45,520
<font color="white" size=".72c">and has a mass equivalent to about 10</font>

662
00:24:42,960 --> 00:24:47,200
<font color="white" size=".72c">000 times that of the milky way</font>

663
00:24:45,520 --> 00:24:48,960
<font color="white" size=".72c">four times greater than the mass</font>

664
00:24:47,200 --> 00:24:51,120
<font color="white" size=".72c">observed in the region of the greater</font>

665
00:24:48,960 --> 00:24:52,720
<font color="white" size=".72c">tractor by the same project</font>

666
00:24:51,120 --> 00:24:55,200
<font color="white" size=".72c">and so it is now believed that this</font>

667
00:24:52,720 --> 00:24:57,279
<font color="white" size=".72c">supercluster is contributing the lion's</font>

668
00:24:55,200 --> 00:25:00,720
<font color="white" size=".72c">share of influence responsible for the</font>

669
00:24:57,279 --> 00:25:02,799
<font color="white" size=".72c">milky way's peculiar velocity</font>

670
00:25:00,720 --> 00:25:05,120
<font color="white" size=".72c">while everything in our supercluster is</font>

671
00:25:02,799 --> 00:25:07,279
<font color="white" size=".72c">flowing towards the greater tractor</font>

672
00:25:05,120 --> 00:25:10,880
<font color="white" size=".72c">the greater tractor itself is being</font>

673
00:25:07,279 --> 00:25:12,880
<font color="white" size=".72c">pulled towards the shapley supercluster</font>

674
00:25:10,880 --> 00:25:14,080
<font color="white" size=".72c">yes the reason that the milky way is</font>

675
00:25:12,880 --> 00:25:16,320
<font color="white" size=".72c">being pulled so quickly</font>

676
00:25:14,080 --> 00:25:18,640
<font color="white" size=".72c">towards centaurus is due to the fact</font>

677
00:25:16,320 --> 00:25:19,600
<font color="white" size=".72c">that it is not just the greater tractor</font>

678
00:25:18,640 --> 00:25:22,799
<font color="white" size=".72c">attracting us</font>

679
00:25:19,600 --> 00:25:24,480
<font color="white" size=".72c">in that direction our peculiar velocity</font>

680
00:25:22,799 --> 00:25:26,320
<font color="white" size=".72c">is likely the result of a compound</font>

681
00:25:24,480 --> 00:25:28,480
<font color="white" size=".72c">effect with the greater tractor</font>

682
00:25:26,320 --> 00:25:31,120
<font color="white" size=".72c">responsible for about 44</font>

683
00:25:28,480 --> 00:25:33,520
<font color="white" size=".72c">of the motion being closer to us and the</font>

684
00:25:31,120 --> 00:25:35,600
<font color="white" size=".72c">remaining 56 percent of our velocity</font>

685
00:25:33,520 --> 00:25:37,520
<font color="white" size=".72c">owes to the much more massive and remote</font>

686
00:25:35,600 --> 00:25:39,520
<font color="white" size=".72c">shapley supercluster</font>

687
00:25:37,520 --> 00:25:41,039
<font color="white" size=".72c">which is dragging the greater tractor</font>

688
00:25:39,520 --> 00:25:42,000
<font color="white" size=".72c">and thus the galaxies in our</font>

689
00:25:41,039 --> 00:25:45,360
<font color="white" size=".72c">supercluster</font>

690
00:25:42,000 --> 00:25:47,200
<font color="white" size=".72c">along with it and so it was</font>

691
00:25:45,360 --> 00:25:49,760
<font color="white" size=".72c">with this crucial piece of the puzzle</font>

692
00:25:47,200 --> 00:25:52,000
<font color="white" size=".72c">that astronomers at hawaii university</font>

693
00:25:49,760 --> 00:25:53,600
<font color="white" size=".72c">were able to redefine the boundaries of</font>

694
00:25:52,000 --> 00:25:55,360
<font color="white" size=".72c">our local supercluster</font>

695
00:25:53,600 --> 00:25:56,960
<font color="white" size=".72c">using the great attractor and the</font>

696
00:25:55,360 --> 00:25:57,919
<font color="white" size=".72c">effects of the more remote shapley</font>

697
00:25:56,960 --> 00:26:00,320
<font color="white" size=".72c">attractor</font>

698
00:25:57,919 --> 00:26:04,080
<font color="white" size=".72c">to map our galactic colony and define</font>

699
00:26:00,320 --> 00:26:04,080
<font color="white" size=".72c">the lanikia supercluster</font>

700
00:26:05,120 --> 00:26:10,159
<font color="white" size=".72c">but there was one more piece of the</font>

701
00:26:06,720 --> 00:26:11,679
<font color="white" size=".72c">mystery which we had yet to discover</font>

702
00:26:10,159 --> 00:26:14,320
<font color="white" size=".72c">when the shapley attractor was</font>

703
00:26:11,679 --> 00:26:15,520
<font color="white" size=".72c">identified astronomers speculated that</font>

704
00:26:14,320 --> 00:26:17,919
<font color="white" size=".72c">there may be another</font>

705
00:26:15,520 --> 00:26:19,760
<font color="white" size=".72c">even more remote galaxy supercluster</font>

706
00:26:17,919 --> 00:26:23,039
<font color="white" size=".72c">which is also contributing to our</font>

707
00:26:19,760 --> 00:26:26,159
<font color="white" size=".72c">perceived movement across space</font>

708
00:26:23,039 --> 00:26:27,840
<font color="white" size=".72c">and only five years ago did renee cron</font>

709
00:26:26,159 --> 00:26:29,600
<font color="white" size=".72c">cortez and her team</font>

710
00:26:27,840 --> 00:26:31,840
<font color="white" size=".72c">the same team that discovered the norma</font>

711
00:26:29,600 --> 00:26:33,679
<font color="white" size=".72c">cluster some 20 years prior</font>

712
00:26:31,840 --> 00:26:37,039
<font color="white" size=".72c">finally solved the mystery that they had</font>

713
00:26:33,679 --> 00:26:40,640
<font color="white" size=".72c">been studying for many decades</font>

714
00:26:37,039 --> 00:26:42,480
<font color="white" size=".72c">in 2016 kron courtferg and her team</font>

715
00:26:40,640 --> 00:26:44,559
<font color="white" size=".72c">announced the discovery of a new</font>

716
00:26:42,480 --> 00:26:45,600
<font color="white" size=".72c">supercluster in the zone of avoidance</font>

717
00:26:44,559 --> 00:26:47,520
<font color="white" size=".72c">region</font>

718
00:26:45,600 --> 00:26:49,760
<font color="white" size=".72c">even further beyond than the shapley</font>

719
00:26:47,520 --> 00:26:52,000
<font color="white" size=".72c">supercluster</font>

720
00:26:49,760 --> 00:26:54,080
<font color="white" size=".72c">using data from the anglo-australian</font>

721
00:26:52,000 --> 00:26:54,960
<font color="white" size=".72c">telescope and the southern african large</font>

722
00:26:54,080 --> 00:26:57,760
<font color="white" size=".72c">telescope</font>

723
00:26:54,960 --> 00:27:00,240
<font color="white" size=".72c">they identified a region of over-density</font>

724
00:26:57,760 --> 00:27:03,679
<font color="white" size=".72c">consistent with a galactic supercluster</font>

725
00:27:00,240 --> 00:27:06,400
<font color="white" size=".72c">around 800 million light years away</font>

726
00:27:03,679 --> 00:27:07,600
<font color="white" size=".72c">this galaxy cluster termed the velar</font>

727
00:27:06,400 --> 00:27:10,320
<font color="white" size=".72c">supercluster</font>

728
00:27:07,600 --> 00:27:11,600
<font color="white" size=".72c">is the final piece of the puzzle thought</font>

729
00:27:10,320 --> 00:27:13,919
<font color="white" size=".72c">to contribute at least</font>

730
00:27:11,600 --> 00:27:16,000
<font color="white" size=".72c">50 kilometers a second to our peculiar</font>

731
00:27:13,919 --> 00:27:18,240
<font color="white" size=".72c">velocity</font>

732
00:27:16,000 --> 00:27:20,480
<font color="white" size=".72c">with the influence of the norma cluster</font>

733
00:27:18,240 --> 00:27:22,480
<font color="white" size=".72c">the shapley attractor and a little help</font>

734
00:27:20,480 --> 00:27:24,159
<font color="white" size=".72c">from the velar supercluster</font>

735
00:27:22,480 --> 00:27:26,080
<font color="white" size=".72c">the observed effects of the great</font>

736
00:27:24,159 --> 00:27:26,720
<font color="white" size=".72c">attractor that were noticed all those</font>

737
00:27:26,080 --> 00:27:34,630
<font color="white" size=".72c">years ago</font>

738
00:27:26,720 --> 00:27:52,069
<font color="white" size=".72c">can finally be explained</font>

739
00:27:34,630 --> 00:27:52,069
<font color="white" size=".72c">[Music]</font>

740
00:27:53,360 --> 00:27:58,080
<font color="white" size=".72c">so with all these things considered what</font>

741
00:27:55,440 --> 00:28:00,080
<font color="white" size=".72c">will be the outcome for us</font>

742
00:27:58,080 --> 00:28:01,360
<font color="white" size=".72c">will we be pulled into the center of the</font>

743
00:28:00,080 --> 00:28:02,720
<font color="white" size=".72c">greater tractor</font>

744
00:28:01,360 --> 00:28:04,880
<font color="white" size=".72c">will the rest of the lenny kia</font>

745
00:28:02,720 --> 00:28:08,159
<font color="white" size=".72c">supercluster will it destroy</font>

746
00:28:04,880 --> 00:28:11,679
<font color="white" size=".72c">our galaxy in the process</font>

747
00:28:08,159 --> 00:28:13,279
<font color="white" size=".72c">well the answer is almost certainly no</font>

748
00:28:11,679 --> 00:28:15,600
<font color="white" size=".72c">while we are being lugged in the</font>

749
00:28:13,279 --> 00:28:17,440
<font color="white" size=".72c">direction of these superclusters against</font>

750
00:28:15,600 --> 00:28:19,440
<font color="white" size=".72c">the expansion of the universe</font>

751
00:28:17,440 --> 00:28:21,760
<font color="white" size=".72c">the force that drives the hubble flow is</font>

752
00:28:19,440 --> 00:28:23,440
<font color="white" size=".72c">accelerating</font>

753
00:28:21,760 --> 00:28:25,919
<font color="white" size=".72c">we will never reach the shapley</font>

754
00:28:23,440 --> 00:28:27,360
<font color="white" size=".72c">supercluster or even the greater tractor</font>

755
00:28:25,919 --> 00:28:29,440
<font color="white" size=".72c">for that matter</font>

756
00:28:27,360 --> 00:28:31,679
<font color="white" size=".72c">as before long dark energy will have</font>

757
00:28:29,440 --> 00:28:33,600
<font color="white" size=".72c">inflated the universe so aggressively</font>

758
00:28:31,679 --> 00:28:35,440
<font color="white" size=".72c">that the influences of the great and</font>

759
00:28:33,600 --> 00:28:38,159
<font color="white" size=".72c">shapley attractors will no longer be</font>

760
00:28:35,440 --> 00:28:40,159
<font color="white" size=".72c">able to overcome it</font>

761
00:28:38,159 --> 00:28:42,480
<font color="white" size=".72c">though we are moving towards centaurus</font>

762
00:28:40,159 --> 00:28:44,480
<font color="white" size=".72c">right now the only thing we are headed</font>

763
00:28:42,480 --> 00:28:46,080
<font color="white" size=".72c">for is a collision with andromeda</font>

764
00:28:44,480 --> 00:28:48,399
<font color="white" size=".72c">and anything else which remains in the</font>

765
00:28:46,080 --> 00:28:50,880
<font color="white" size=".72c">local group</font>

766
00:28:48,399 --> 00:28:52,240
<font color="white" size=".72c">our only eventual destination is the</font>

767
00:28:50,880 --> 00:28:54,799
<font color="white" size=".72c">void</font>

768
00:28:52,240 --> 00:28:56,240
<font color="white" size=".72c">the great attractor like all galaxy</font>

769
00:28:54,799 --> 00:28:58,559
<font color="white" size=".72c">clusters and groups</font>

770
00:28:56,240 --> 00:28:59,600
<font color="white" size=".72c">will be dispersed into its constituent</font>

771
00:28:58,559 --> 00:29:01,840
<font color="white" size=".72c">galaxies</font>

772
00:28:59,600 --> 00:29:03,840
<font color="white" size=".72c">each being cast into its own section of</font>

773
00:29:01,840 --> 00:29:06,799
<font color="white" size=".72c">space thanks to the force that drives</font>

774
00:29:03,840 --> 00:29:09,200
<font color="white" size=".72c">the universe's inflation</font>

775
00:29:06,799 --> 00:29:11,279
<font color="white" size=".72c">but hey right now the separation of</font>

776
00:29:09,200 --> 00:29:12,960
<font color="white" size=".72c">galaxies hasn't occurred yet</font>

777
00:29:11,279 --> 00:29:14,720
<font color="white" size=".72c">and it's going to be a pretty long time</font>

778
00:29:12,960 --> 00:29:16,960
<font color="white" size=".72c">before it does</font>

779
00:29:14,720 --> 00:29:18,799
<font color="white" size=".72c">and we are fortunate enough to exist at</font>

780
00:29:16,960 --> 00:29:21,279
<font color="white" size=".72c">a time when we can observe brilliant</font>

781
00:29:18,799 --> 00:29:24,840
<font color="white" size=".72c">cosmic structures like leniencia</font>

782
00:29:21,279 --> 00:29:27,360
<font color="white" size=".72c">without them vanishing over the cosmic</font>

783
00:29:24,840 --> 00:29:29,679
<font color="white" size=".72c">horizon there's just something about</font>

784
00:29:27,360 --> 00:29:30,159
<font color="white" size=".72c">galaxies flowing like great lakes across</font>

785
00:29:29,679 --> 00:29:33,200
<font color="white" size=".72c">space</font>

786
00:29:30,159 --> 00:29:35,120
<font color="white" size=".72c">that seems tantalizing and beautiful and</font>

787
00:29:33,200 --> 00:29:37,840
<font color="white" size=".72c">it is remarkable just how far</font>

788
00:29:35,120 --> 00:29:40,000
<font color="white" size=".72c">gravity propagates and though the great</font>

789
00:29:37,840 --> 00:29:42,480
<font color="white" size=".72c">attractor was a gravitational mystery</font>

790
00:29:40,000 --> 00:29:43,200
<font color="white" size=".72c">for many years the biggest unsolved</font>

791
00:29:42,480 --> 00:29:55,840
<font color="white" size=".72c">mystery</font>

792
00:29:43,200 --> 00:29:55,840
<font color="white" size=".72c">is gravity itself</font>

793
00:29:58,980 --> 00:30:07,960
<font color="white" size=".72c">[Music]</font>

794
00:30:12,960 --> 00:30:15,039
<font color="white" size=".72c">you</font>