the universes story of a life time

8/7/2019 The Universes Story of a life time

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By: Adrian Estrada



In medieval times, before the great voyages of discovery and

exploration that began in the 15th

century, people assumedthat the earth was the whole universe. Many peoplesupported the idea of a flat earth-go to far and you would fallover the edge.



The last of the great classical astronomers, an Alexandrain

Greek named Ptolemy, summed up the ancient concept of theuniverse in about AD 150. The Ptolemy Universe had theEarth at it’s center, with the sun, moon, and planets circlingaround it, within a sphere of fixed stars.



In 1543, Astronomy was revolutionized when Copernicus put

forward the idea of a sun-centered universe. In theCopernicus system, the earth and other planets traveledaround the sun in circular orbits, but astronomers couldn’tmatch the observed motions of the planets with this idea.Then German Johannes Kepler discovered why-the planetstraveled around the sun not in circles, but in ellipses. Thisdiscovery formed Kepler’s first law of planetary motion.



Echoes of the big bang

If the Big Bang really happened, physicists calculate that by now thetemperature of the whole universe would have fallen to about 5.5f

above absolute zero. In 1965, U.S. physicists Arno Penzias andRobert Wilson picked up a weak radio signals coming from all parts of the sky. They were equivalent to a cosmic background temperaturearound -454

f proving evidence for the Big Bang.



If there is enough matter in the universe, gravity will

eventually stop it from expanding. Maybe it will open thencontract, with all its matter pulled together into an infinitelysmall point. This “Big Crunch” might then be followed byanother Big Bang to create a new , expanding Universe. But if there is not enough matter in our universe, it will continueforever.



A new born star is surrounded by a swirling disk of matter

with perhaps three times its mass, but not for ling. Powerfulstellar winds gather up the matter and force it away from thestar’s poles as twin jets. This is called outflow.



Iron builds up rapidly in a supergiant’s core- it cannot beburned by the nuclear reactions in the same way as lighterelements. When the core runs out of other fuel, it cannotsupport itself and suddenly collapses. So much energy isreleased that the star blasts itself apart in a supernova explosionthat can briefly outshine an entire galaxy. The explosion scattersheavy elements across space, providing material for later of starsand planets



When a collapsing star’s core is massive enough, it goes past

the neutron star stage and keeps on shrinking, with itsgravity growing stronger all the time. Think of space as thinrubber sheet. If you place a heavy object on the sheet, it willmake a dent-a “gravitational well” .



Most galaxies give out the energy of hundreds of billions of

stars shining together, but some give out much more. We callthese active galaxies, and the include Radio galaxies,

Quasars, Blazars, and Seyfert galaxies.



Anti matter is said to end all life in the universe. WhenMatter an Anti matter come in contact with each other,devastating results will happen. There will be the biggestexplosion ever.

the universes story of a life time

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