The Universe The Universe

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The Universe The Universe Powered By Docstoc
					The Universe
The universe is the sum of all matter and
energy that exists, that has ever existed, or that
ever will exist.
There is only ONE universe. You are part of
the universe, as is the Earth and everything on
it.
Red Shift
   • In 1929, Edwin Hubble
     observed the light being
     emitted by other galaxies
     was redder than expected.
     This shift toward the red end
     of the spectrum means the
     galaxies were moving away
     from us. The farther away
     they were the faster they
     were going.
   • This was interpreted to
     mean the universe is
     expanding.
  How do we measure distance in
            space?
• Distance in space is hard to imagine
  because space is so vast.
• You need something bigger than miles
  and kilometers to measure these large
  distances.
• Units of measure must have meaning to
  the people who use them and be
  functional for the purpose they are created
  for.
        Astronomical units
• An astronomical units (AU) equals
  150,000,000 km (150 million)—which is
  the average distance the Earth is from
  the sun.

• If something is 5 AU away, it means the object is five (5)
  times as far away from Earth as the Earth is from the
  sun.

• Mercury is 0.38 AU; the Earth is 1 AU, and Pluto is 39 AU
  from the sun.
             Light Years
•Distances between Galaxies are measured
 in light-years (ly).
•A light-year is the distance light travels in
 one year—approximately 9.5 trillion km
 (9.5 X 1015 km)
•Light travels so fast, it could go around the
 Earth seven times in one second.
    The Origin of the Universe
• How did the universe begin? This is a
  question that scientists are trying to
  answer by studying the stars, galaxies,
  and planets in our solar system.
• Cosmology is the study of the origin and
  evolution of the universe.
• Several theories exists about the origin of
  the universe.
The Big Bang Theory
          • According to the Big
            Bang Theory, the
            universe was created
            10 to 20 billion years
            ago with a gigantic
            explosion that hurled
            matter in all
            directions.
The Big Bang Theory is the dominate theory
      about the origin of the universe.
           Big Bang Theory
• According to the theory, during the
  expansion after the explosion, it cooled the
  universe enough to form matter in the form
  of neutrons, protons, and electrons. After
  a million years, the universe cooled
  enough for hydrogen atoms to form. Since
  then hydrogen has been the most
  abundant element on Earth.
         Inflationary Theory
• This is basically an expansion of the Big
  Bang Theory.

• This theory states that during earlier
  stages of development, the universe
  expanded at a faster rate than it is
  expanding today.
       Steady-State Theory
• This theory does not propose a
  beginning of time.

• It simply states that the universe has
  always existed in relatively the same
  state it is now and that it will remain
  the same forever.
How do we explore space?
                          The telescope
                                        • The origin of the
                                          telescope is
                                          surrounded by
                                          controversy, the
                                          most likely story
                                          puts it in the shop of
•The earliest known illustration of a     a Dutch spectacle
telescope.
Giovanpattista della Porta included       maker named Hans
this sketch in a letter written in
August 1609
                                          Lippersey in 1608.
        Refracting Telescope
                               • The lenses used in
                                 refracting telescopes are
                                 called concave and
                                 convex. Convex (curved
                                 outward) lenses make
                                 things bigger, but blurry.
                                 Concave (curved inward)
                                 lenses make things look
                                 clearer, but small. As you
                                 can guess, a combination
                                 of these two lenses
Refracting telescopes (or
                                 makes things seem
refractors) use lenses to
                                 bigger and clearer.
gather and bend light making
things seem larger.
    What happens when you look
      through the telescope?
• Imagine we are still outside looking at Venus
  with a refracting telescope. An objective, or
  large, lens collects light from Venus and sends
  it to a smaller, eyepiece lens at the back of the
  telescope tube. The eyepiece magnifies the
  little image of Venus and directs it at your eye.
  Wow, can you see the yellow-white disk? Now
  that's some planet!
              Reflecting Telescope
                                         • Our reflecting telescope
                                           uses mirrors to collect
                                           and magnify light.
                                           Remember that reflecting
                                           telescopes originally
                                           developed to solve the
                                           problem of color
                                           distortions caused by
                                           lenses bending light at
                                           different angles. The
Let's say we are still outside looking     reflecting telescope's
at Venus, but now we are using a           mirror reflects light
reflecting telescope (or reflector).       instead of bending it so
                                           there is no color
                                           distortion.
• With our reflecting telescope, light is
  collected by a big concave mirror. The
  mirror reflects light to a smaller flat mirror.
  This secondary mirror directs the light from
  Venus through the eyepiece lens at the
  side of the telescope. The eyepiece
  magnifies the image. Yep, when we look
  through the eyepiece,
• we can see Venus !
              Telescope Facts
• The largest optical telescope in the world is in Hawaii.
  It's the 10-meter W. M. Keck telescope. At 4300 meters,
  it sits on top of Mount Mauna Kea, an extinct volcano.
      Radio telescopes use a large dish to collect radio
  waves from space. The dish is the same shape as the
  mirror of a reflecting telescope. Radio telescopes are a
  valuable tool for astronomers since many objects in the
  universe do not produce enough visible light to be picked
  up by optical telescopes. One of the world's most
  powerful radio telescopes is the Very Large Array (VLA)
  in New Mexico. The VLA is made up of 27 linked radio
  telescope dishes each 25 meters in diameter.
      The Importance of Light
• Most of what we know about the Universe
  comes from information that has been
  carried to us by light. But we have seen
  that visible light is only a small part of the
  electromagnetic spectrum. In recent years
  the remainder of the electromagnetic
  spectrum has revealed extensive
  information about our Universe.
• Radio waves have the longest wavelengths in the
  electromagnetic spectrum. These waves can be longer
  than a football field or as short as a football. Radio
  waves do more than just bring music to your radio. They
  also carry signals for your television and cellular phones.
Radio Telescopes
        • Detect radio signals
          emitted by distant
          objects. Some of the
          oldest, most distant
          objects in the solar
          system have been
          detected by radio
          telescopes.
        • Radio waves from those
          objects were emitted
          almost 15 billion years
          ago.
   How do we "see" using Radio
            Waves?
• Objects in space, such as planets and comets, giant
  clouds of gas and dust, and stars and galaxies, emit light
  at many different wavelengths. Some of the light they
  emit has very large wavelengths - sometimes as long as
  a mile!. These long waves are in the radio region of the
  electromagnetic spectrum.
• Because radio waves are larger than optical waves,
  radio telescopes work differently than telescopes that we
  use for visible > light (optical telescopes). Radio
  telescopes are dishes made out of conducting metal that
  reflect radio waves to a focus point. Because the
  wavelengths of radio light are so large, a radio telescope
  must be physically larger than an optical telescope to be
  able to make images of comparable clarity. For example,
                      Parkes Radio
                       Telescope
• The Parkes radio telescope,
  which has a dish 64 meters
  wide, cannot give us any
  clearer an image than a small
  backyard telescope! In order to
  make better and more clear (or
  higher resolution) radio
  images, radio astronomers
  often combine several smaller
  telescopes, or receiving
  dishes, into an array. Together,
  the dishes can act as one large
  telescope whose size equals        Time-lapse view of Parkes radio
  the total area occupied by the     telescope at night in New South
  array.                             Wales, Australia
       The Hubble Telescope
• Named for Edwin
  Hubble, the Hubble
  Space Telescope now
  probes the depths of
  the universe from it’s
  orbit high above the
  Earth’s atmosphere.
Hubble Space Telescope
Space Flights
Sputnik
    • Sputnik was the first man-
      made satellite.
    • Many consider October 4,
      1957 to be the beginning of the
      Space Age. On this date,
      Sputnik — a basketball-sized,
      Soviet-made satellite —
      orbited our planet. Due to cold-
      war tension between the
      world’s superpowers — the
      United States and the Soviet
      Union (now Russia) — the
      Sputnik launch fueled the
      space race between the two
      countries.
          BIRTH OF A SATELLITE
•   Sputnik I's vital statistics

•   Launch date: Oct. 4, 1957
•   Diameter: 23 inches
•   Weight: 183 pounds
•   Material: Aluminum alloy
•   Life span: About 22 days, ending when transmitter batteries expired
•   Name: Translates to "fellow traveler" or "traveling companion" in English
•   Function: Gathered data on the atmosphere, emitted beeps, tested radio transmission
•   Impact on pop culture: Amid concerns about what Sputnik meant regarding the Soviets'
    space and military capabilities, Americans began to riff on the Sputnik theme.
•   Bars offered vodka-based Sputnik cocktails; restaurants named sandwiches after the
    satellite. There were Sputnik toys and bubble gum, and satellite-shaped ceiling lamps,
    earrings and Christmas ornaments.
•   Several musicians penned Space Age songs, such as one by Al Barkle with the Tri-Tones
    that began with Barkle imitating the satellite's beeping.
•   Sources: NASA; Russian space writer Anatoly Zak; After Sputnik: 50 Years of the Spage
    Age
          Space Race Milestones

•   Wide-open spaces: An astronaut
    enjoys a spacewalk. Image courtesy
    of NASA
•   Intense research and development
    ensued over the following decades.
    Successes by both nations are marked
    by important milestones:
•   First person in space — The Russian
    astronaut Yuri Gagarin achieved this
    on April 12, 1961.
•   First person in space — First person
    to orbit Earth – American John Glen
    orbited Earth on Feb. 20, 1962.
•   First person in space — First moon
    walk – Neil Armstrong and Buzz Aldrin
    were the first people to set foot on the
    Moon on July 20, 1969, answering the
    challenge of former U.S. President
    John F. Kennedy.
                      On the Horizon

•   Currently, both nations maintain active
    space programs. Other countries, such
    as France, Japan, and China now
    have space programs as well. Current
    space exploration endeavors include:
•   Deployment of reusable spacecraft,
    called space shuttles
•   International Space Station
•   Orbiting space telescope (Hubble
    Space Telescope)
•   Unmanned missions to explore Mars
•   The future of space exploration may
    include bold projects such as a lunar     An artist's concept of a Mars
    colony and manned missions to Mars.
    Many technological challenges must        rover - a remotely controlled
    be overcome to succeed in these           vehicle that traverse the
    missions. However, that’s never
    stopped us before . . .                   Martian surface and send data
                                              to scientists on Earth. Image
                                              courtesy of NASA

				
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