Stars

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?Stars ?

• ?We Are ALL Made of Stardust!?
• ?By Ashley Gray?

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?What are Stars? ?
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• ? A star is an enormous ball of gas. Sizes vary
  ranging from small stars to very massive stars,
  known as giants or super giants. Our sun is a
  medium sized star.
• ? A stars color depends on its temperature.
  Blue is the hottest, and red the coolest.
• ? If a star has more mass, the star dies quicker
  than a star with less mass. You may think that
  because their bigger, they have more energy to
  burn. But they just use their energy a lot
  quicker in order to stay alive.
• ? Stars are bright because of the atomic
  collisions happening inside a star.

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?Why do Stars Shine? ?

• ? Enormous atomic collisions occur in the center
  of stars. These collisions cause atoms inside the
  star to be separated which alters the atomic
  structure. This makes an enormous amount of
  energy, which a star radiates as brightness and
  heat.

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?Creation of the Elements ?

• ? Nuclear fusion powers stars. It happens when
  several nuclei combines with each other to make a
  larger nuclei, creating a new element. This
  process results in a lot of energy which the star
  radiates into light and heat.

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?Life Cycle of Stars ?
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?Nebula ?

• ? A nebula is a large cloud of dust, gas, and
  intergalactic space. The gas in a nebula is
  mostly hydrogen.
• ? Stars are formed in a nebula. The nebula is
  bright from the light radiated by newborn stars.
• ? Theyre formed by a shell of gas ejected by a
  red giant or super red giant.

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?Red Giant ?
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• ? When a star is close to death, it begins to
  expand. This is what we know as a red giant.
• ? Medium sized stars swell up, and become a red
  giant.
• ? As a star grows old, their core runs out of
  hydrogen and helium and then cools as it expands.
  They become less bright and turn into a red
  giant.
• ? After being a red giant, a medium size star
  becomes a planetary nebula. After that a white
  dwarf, then a black dwarf.

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?Super Red Giant ?

• ? A red super giant is similar to a red giant,
  but only the massive stars become a super red
  giant. They are bigger, as the stars were before
  they expanded.
• ? Massive stars become a super red giant close
  to death, before becoming a supernova.
• ? Super red giants are very large, and only
  stars over 1.5 times the mass of our sun can be
  one.
• ? After the star is born, it starts to get
  cooler and expands as it ages. It soon becomes a
  super red giant.
• ? Super red giants become a supernova, then,
  depending on whether they are massive or very
  massive, they turn into a neutron star or a black
  hole.

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?White Dwarf ?

• ? After a star runs out of nuclear fuel, it
  becomes a white dwarf. White dwarves are stable,
  and radiate any left over heat they have.
• ? When a star becomes a white dwarf, it is very
  close to its death.
• ? Medium sized stars become white dwarves.
• ? Before becoming a white dwarf, a star was a
  red giant.
• ? A star will become a black dwarf when it
  radiates all of its heat.

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?Black Dwarf ?

• ? A black dwarf is a cold, dead star. It has no
  more energy left to radiate.
• ? All medium sized stars will become a black
  dwarf.
• ? Before becoming a black dwarf, it was a white
  dwarf. When a white dwarf burns all its leftover
  energy, they become black dwarves.
• ? This is the end of a medium sized stars life
  cycle.

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?Supernova ?
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• ? A supernova is a collapsed red giant. The
  electrical forces overcome the gravitational
  forces inside the star, and causes a big, short
  explosion, blowing away all of the stars outer
  layers.
• ? This is the stage right before the death of a
  massive or very massive star.
• ? Massive and very massive stars become
  supernovas.
• ? Before blowing up, a supernova was a red
  giant.
• ? A supernova will become a neutron star.

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?Black Hole ?
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• ? When the explosion of a supernova contracts,
  it sometimes makes a black hole if the star was
  really massive. A black hole is a dense hole,
  with a strong gravitational pull. Even light, the
  fastest moving thing we know of, cannot escape a
  black hole.
• ? A black hole is the end of a stars life cycle.
• ? Really massive stars, 3 times the mass of our
  sun or more, become black holes.
• ? Before becoming a black hole, the star was
  supernova, which contracted.
• ? A black hole is the end of a stars life.

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?Neutron Star ?

• ? When a massive star explodes, the contraction
  of the star causes a neutron star.
• ? This is the end of a stars life.
• ? Only massive stars, about 1.5 to 3 times the
  mass of the sun, can become a neutron star.
• ? The neutron star was a supernova before the
  star it contracted.
• ? It is now a dead star, and this is the end of
  the star.

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?Our Sun ?
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?Credits ?

• ? Zoom Astronomy, http//www.enchantedlearning.co
  m/subjects/astronomy/stars/
• ? http//imagine.gsfc.nasa.gov/docs/ask_astro/ans
  wers/971016.html

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