UNFOLDING UNIVERSE Discovery Channel Productions 2002 View of the universe is changing—scales expanding Our sense of time has changed Universe began 15 billion years ago at the Big Bang Matter began contracting ½ billion years later the first big star formed by hydrogen fusion Oxygen, carbon, iron created and pulled into core of star Detonation due to collapse—supernova 100 billion stars in the Milky Way Gravity draws them together Hydrogen and heavy supernova elements mixed by gravity Clumps of gas became stars—clustered Swirled, merged into large galaxies Process continues today Spinning clump became very thin dish 100 billion galaxies in visible universe Milky Way galaxy is extremely flat, with a bulge in the center Spiral arms along outskirts 300 million years for Sun to orbit galaxy, from 2/3 out one spiral arm Center of galaxy so chaotic no life there: radiation, gravity, explosions Stars traveling at 3,000,000 miles/hour at center of Milky Way Gravity has created solar system and galaxy Einstein imagined class of objects so massive that light could not escape He called them ‘dark stars’, today known as ‘Black Holes’ Neil Tyson describes the ‘spaghettification’ of objects as they are drawn into black holes—torn apart vertically with increasing acceleration Chandra Observatory views galaxy—contains bright stars devouring other stars It also has massive black hole Inferred by enormous speed of stars orbiting the black hole Universe being mapped by observers at Keck Telescope Observes solar system sized area of stars with a black hole at center Matter of black hole the size of a speck of dust is 3,000,000 times mass of Sun Black hole at center of Milky Way is a hungry dragon devouring anything that strays into its gravity. Perhaps massive size because it has consumed other black holes. Dense star clusters and gases are flowing into the black hole. Each star and cloud that enters increases its mass, becomes larger Sun’s evolution 5 billion years from now Sun will become a Red Giant 10,000 times brighter than it is today Expand to engulf the entire orbit of Earth Gravity holds Sun together Hydrogen fusion generates pressure that holds gas out from centerAs Sun’s core consumes core hydrogen, the burning area will expand Sun’s core 1,000,000 degrees as heavier elements fall into it Will begin to fuse higher elements than helium Earth’s oceans will boil as Sun heats and expands Fred Adams projects future of our solar system, and Suggests we can save ourselves Build space stations and go live somewhere else or Steer our planet to more habitable climes of our solar system by manipulation of our orbit by the gravity of asteroids Another galaxy is approaching the Milky Way Apache Point, NM mapping universe Has located 1,000,000 galaxies Grouped along ‘spiderwebs’ with lots of emptiness between Milky Way is traveling toward Virgo Supercluster Our ‘local group’ includes the Andromeda Galaxy—approaching us Our closest neighbor, converging at 300,000 miles/hour 5-7 billion years from now, Milky Way and Andromeda will pass through one another Will begin to orbit one another May fling much material out of both, rearrange stars in both into a spherical galaxy Cores of the two will orbit one another and eventually merge 25 billion years from the Big Bang until the ‘collision’ with the Andromeda galaxy Our galaxy will change as stars begin to burn out—use up all hydrogen Stars will be devoured by black holes Black holes will consume one another Black holes actually may evaporate one atom at a time A google (that’s 1 with a hundred zeroes) years from now, perhaps the entire galaxy will be contained in a single enormous black
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