The universe2


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The universe2

  1. 1. The Universe
  2. 2. Three Theories about the Origin of the Universe <ul><li>Big Bang Theory – Edwin Hubble </li></ul><ul><li>Steady State Theory – Herman Bondi, Fred Hoyle and Thomas Gold </li></ul><ul><li>Oscillating Universe Theory – Fred Hoyle </li></ul>
  3. 3. 1. The Big Bang Theory <ul><li>The universe started from very hot and dense fire ball also known as YLEM that explodes. Bringing streams of gases containing proton, neutron, and electron to immerse in the vast ocean of radiation. After the explosion, the ylem cooled and contract giving birth to the universe. </li></ul><ul><li>The universe that exist today is a product of continuous expansion and contraction . The expansion still continues and the distance between galaxies continue to increase. </li></ul>
  4. 4. Big Bang Theory
  5. 5. Two Evidences Supporting the BBT <ul><li>1. The Law of Conservation of Matter and Energy </li></ul><ul><li>Matter or energy is neither created nor destroyed it can only be transformed into another form. </li></ul><ul><li>2. The Law of the Expanding Universe. </li></ul><ul><li>Edwin Hubble and Milton Humason were able to determine at which galaxies are moving away from each other. </li></ul><ul><li>55 km per million parsec = the rate by which galaxies are moving. </li></ul>
  6. 6. Our Universe is Expanding <ul><li>In the 1920’s, Edwin Hubble discovered that galaxies were moving away from us when he observed the red shift in light wavelengths emitted by galaxies. </li></ul><ul><li>This is known as Hubble’s law which states that the further away a galaxy is, the greater it’s red shift and the faster it is moving away from us . This led to the calculation of the point where the Big Bang started. </li></ul><ul><li>Today with the Hubble Space Telescope scientists have observed that most of the galaxies are moving away from us and this means that our universe must be moving outwards and expanding. </li></ul>
  7. 7. <ul><li>Vesto Slipher = He studied the spectrum of light emitted by 15 nearby galaxies and noticed that the wavelength of the spectrum shifted to the red indicating that it is moving away. </li></ul>
  8. 8. 2. Steady State Theory <ul><li>This theory proposes that the Universe is the same everywhere and for all time, both in the past and in the future. But calculations suggest that the universe is still expanding, so in order to maintain this constant state, matter must constantly be created out of nothing . </li></ul><ul><li>A steady-state universe has no beginning or end in time; and from any point within it the view on the grand scale--i.e., the average density and arrangement of galaxies--is the same </li></ul>
  9. 9. SST
  10. 10. Evidence Supporting the SST <ul><li>Robert Dicke – the sky is filled with radiation that was formed during the birth of the universe. </li></ul><ul><li>Wilson and Penzias – detected the presence of radiation in the form of radio sounds. </li></ul>
  11. 11. 3. Oscillating Universe Theory <ul><li>Most astronomers agree that the Universe is expanding. </li></ul><ul><li>Some believe that at some stage in the future, the Universe will stop expanding and begin to contract. </li></ul><ul><li>This is what is meant by oscillating which is the forward and backwards motion of the expansion and contraction of the Universe. </li></ul>
  12. 13. Big Crunch
  13. 14. Theories About the Possible Fate of the Universe <ul><li>1. Open Universe </li></ul><ul><li>2. Close Universe </li></ul><ul><li>3. Flat Universe </li></ul>
  14. 15. Theories About the Possible Fate of the Universe <ul><li>1. Open Universe </li></ul><ul><li>2. Close Universe </li></ul><ul><li>3. Flat Universe </li></ul><ul><li>Big Bang theory </li></ul><ul><li>Oscillating Universe </li></ul><ul><li>Steady State </li></ul>
  16. 17. Design of the Universe <ul><li>Galaxy - basic unit the universe is made of. </li></ul><ul><li>Galaxy is made up of billions of stars. </li></ul>
  17. 18. Lightyear <ul><li>The distance traveled the beam of light in one year. </li></ul><ul><li>6 million million miles = 6 trillion miles </li></ul><ul><li>186,000 miles/sec x 60 sec/min x 60 min/hr x 24 hrs/day x 365 days/year </li></ul><ul><li>AlphaCentauri = 4.3 lightyears away from us. It is the nearest star from our planet. </li></ul>
  20. 21. Galaxies have three main components: <ul><li>1. The bulge is a spherical structure found in the center of the galaxy. This feature mostly contains older stars. </li></ul><ul><li>2. The disk is made up of dust, gas, and younger stars. The disk forms arm structures. Our Sun is located in an arm of our galaxy, the Milky Way. </li></ul><ul><li>3. The halo of a galaxy is a loose, spherical structure located around the bulge and some of the disk. The halo contains old clusters of stars, known as globular clusters . </li></ul>
  21. 22. GALAXY <ul><li>Edwin Hubble – the man who classified the galaxies based on shape </li></ul><ul><li>CLASSIFICATION OF GALAXY </li></ul><ul><li>1. Elliptical </li></ul><ul><li>2. Spiral </li></ul><ul><li>3. Irregular </li></ul>
  22. 23. Tuning Fork
  23. 24. <ul><li>Elliptical ( E ) galaxies appear to be elliptical in their two dimensional image and are assumed to be ellipsoidal in three dimensional space. </li></ul><ul><li>Elliptical galaxies have no spiral or bar patterns. Instead they range from nearly perfect spheres (E0) to highly flattened ellipses (E7). </li></ul>
  24. 25. Spiral galaxies are divided into two subclasses: <ul><li>1. Ordinary (designated S or SA) - the arms originate directly from the nucleus of the galaxy. </li></ul><ul><li>2. Barred (designated SB). - a bar of stars cuts through the center of the galaxy and the arms originate from the ends of the bar. </li></ul><ul><ul><li>Both have spiral arms, with two arms generally placed symmetrically about the center of the axis of the rotation. </li></ul></ul><ul><ul><li>Both ordinary and barred galaxies are further classified, starting from `a' to `c' according to how tightly the arms are wound. </li></ul></ul><ul><ul><li>In `Sa' and `SBa,' the arms are tight and they form an almost a circular pattern; </li></ul></ul><ul><ul><li>in `Sb' and `SBb,' they are more open and </li></ul></ul><ul><ul><li>in `Sc' and `SBc' the nuclei are small and have extended arms. The intensity of the spheroidal component of the spiral galaxies, around their nucleus, </li></ul></ul>
  25. 26. Irregular Galaxies <ul><li>Irregular galaxies have no symmetrical or regular structure </li></ul>
  26. 28. Milky way galaxy
  27. 29. <ul><li>Since the galaxy rotates, the Sun &quot;orbits&quot; the centre, taking 200 million years to complete one circuit. </li></ul>
  28. 30. Milky Way Galaxy <ul><li>Spiral in shape </li></ul><ul><li>100,000 ly – diameter </li></ul><ul><li>20,000 ly = distance of the solar system from the edge of the milky way </li></ul><ul><li>3000 lightyears – diameter of the central core </li></ul>
  29. 31. Stars <ul><li>These are large spheres of incandescent gas much like our own sun. </li></ul><ul><li>It begins as a cloud of dust and gas. </li></ul><ul><li>It shines due to the light they produce. </li></ul>
  30. 32. PROPERTIES OF STARS <ul><li>1. Distance </li></ul><ul><li>Friedrick Wilhelm Bessel – introduced a method of measurement called parallax. </li></ul><ul><li>Parallax – the apparent change in the position of the star due to the change in the position of the observer. </li></ul><ul><li>Parallax of the star is actually an angle. </li></ul>
  31. 34. PARALLAX <ul><li>The farther the star is the smaller is the parallax angle formed and the nearer the star is the bigger is the parallax angle formed. </li></ul>
  32. 35. PARSEC <ul><li>Parsec is defined as the distance at which an object has a parallax of one second </li></ul><ul><li>Parsec = 1 </li></ul><ul><li>sec </li></ul><ul><li>1 parsec = 3.26 ly </li></ul><ul><li>= 30 million million km </li></ul>
  33. 36. 2. Magnitude <ul><li>It refes to the brightness of the stars. </li></ul><ul><li>Two ways of describing the brightness of the stars </li></ul><ul><li>1. Apparent Magnitude – the brightness as it appears to the observer. (Hipparchus) </li></ul><ul><li>2. Absolute Magnitude – the brightness the star would have if it were viewed at equal distance with the other stars </li></ul>
  34. 37. 3. SIZE <ul><li>Although these term describe the size of stars, they do not actually refer to size but rather to the brightness of the stars </li></ul><ul><li>Stars with absolute magnitude brighter than 1 are called giants. </li></ul><ul><li>Those with absolute magnitude less than 1 are called dwarfs </li></ul><ul><li>Those that are brighter than giants are supergiants, although some giants are bigger than supergiants. </li></ul>
  35. 38. <ul><li>The absolute magnitude of the stars depends on two things: </li></ul><ul><li>1. Size </li></ul><ul><li>2. Temperature </li></ul>
  36. 39. 4. Color and Temperature COLOR TEMP EXAMPLE RED 1500-3500 Betelgeuse ORANGE 5000 Antares, Arcturus YELLOW 6000 Canopus, Sun WHITE 7500-11,000 Vega BLUISH WHITE Over 25000 Rigel
  37. 40. 5. COMPOSITION <ul><li>A method of classifying stars according to composition using colors of spectrum was introduced by Fr. Angelo Secchi </li></ul>
  38. 41. 6. Mass <ul><li>Stars vary in mass. </li></ul><ul><li>It pertains to the amount of matter present in a given body. </li></ul>
  39. 42. THE LIFE CYCLE OF STARS <ul><li>1. Birth – beginning star is called a protostar. </li></ul><ul><li>2. Infancy – protostar at this stage is now called star. </li></ul><ul><li>3. Maturity – Stable stage. </li></ul><ul><li>4 . Later year – stage wherein most of the H2 atoms have been converted to helium. </li></ul><ul><li>5. Last stage – stars now have helium core and the outer envelop composed of hydrogen. </li></ul>
  40. 43. Star Classes <ul><li>Binary star – stars of unequal magnitude bound together by mutual gravitational force. One revolves around the other. </li></ul><ul><li>Variable stars – whose brightness vary periodically. </li></ul><ul><ul><li>Cepheid variable – pulsating star whose brightness & temperature vary accd’g to regular pattern. As it expands it becomes cooler and dimmer and when it contracts, it becomes hotter & brighter. The brightness may last for a week. </li></ul></ul>
  41. 44. <ul><ul><li>Long period variables – star whose bright and dim period last for 150 days or more. </li></ul></ul><ul><ul><li>Nova or supernova – stars which suddenly becomes very bright and eventually explodes. </li></ul></ul><ul><ul><ul><li>Tycho Brahe – observed the first supernova in 1572 </li></ul></ul></ul>
  42. 45. CONSTELLATION <ul><li>Group of stars that forms a pattern like heroes, animals and objects that were famous in their mythology. </li></ul><ul><li>Johannes Bayer – assigned Greek letters in alphabetical order to the star in each constellation to designate their brightness </li></ul>
  43. 46. Zodiacal Constellation <ul><li>Aries – the ram </li></ul><ul><li>Taurus – the bull </li></ul><ul><li>Gemini – the twin </li></ul><ul><li>Cancer – the crab </li></ul><ul><li>Virgo – the virgin </li></ul><ul><li>Libra – the scale </li></ul><ul><li>Scorpio - the scorpion </li></ul><ul><li>Sagittarius – the archer </li></ul><ul><li>Capricorn – the sea goat </li></ul><ul><li>Aquarius - the water carrier </li></ul><ul><li>Pisces – the fish </li></ul><ul><li>Leo – the lion </li></ul>