SCIENCE STARS AND CONSTELL

• Star

  A huge ball of very hot gases like hydrogen and helium
• Our sun is the closest star to our planet
• Stars

  • Give off light and heat energy

  
• Ways scientists classify stars

  • By color
  • By brightness
  • By size

  
• Star colors

  • Blue (hottest)
  • White
  • Yellow
  • Orange
  • Red (coolest)
• Star color


  Indicates the temperature of the star
• Red stars are the coldest and blue stars are the hottest
• Star brightness

  Depends on how far it is from Earth and how bright it actually is
• Star sizes

  • Some stars are smaller than Earth
  • The smallest stars are called neutron stars
  • Some stars are similar in size to Earth, called dwarf-stars
  • When stars are bigger than Earth, they're called giant-stars
• Our Sun

  A yellow star, medium size, medium brightness
• Star formation

  1. Clouds of swirling dust

  2. Gravity squeezes the cloud

  3. Cloud circles faster and faster

  4. Cloud is called a nebula

  5. A star is born
• Life cycle of small stars

  1. Grow to a Red Giant

  2. Die and become a White Dwarf
• Life cycle of big stars

  1. Explode and are called Super Novas

  2. Some Super Giant stars explode and make a black hole
• Nothing can escape a black hole's suction because of gravity
• Our sun will grow to be a Red Giant and then a White Dwarf
• Kinds of stars

  • Red Giant
  • Super Giant
  • Dwarf Stars
• Red Giant


  • Large red star at least 10x diameter of the sun
  • Old stars
  • Example: Aldebaran
• Super Giant

  • Largest of all stars 100x more luminous
  • Some are almost as large as our entire solar system
  • Explode as a Super Nova
  • Can form Black Holes
  • Examples: Betelgeuse, Rigel, Polaris
• Dwarf Stars

  • Less luminous
  • Very dense, mostly carbon
  • Tightly packed nuclei
  • Most are red/orange/yellow
  • Sun is a yellow dwarf
• Star colors and examples

  • Blue - hottest stars (Rigel, Vega, Sirius)
  • Yellow - medium stars (Sun)
  • Red - coolest stars (Betelgeuse, Antares, Aldebaran)
• The Sun is an average star, yellow in color, 300,000 x the mass of Earth
• Constellation


  Bright stars that may appear to form a group or pattern
• There are 88 constellations in all
• Most constellations were named many years ago, after the shapes of animals or their gods
• Orion


  One of the brightest constellations, a mythological character who was a hunter that bragged too much, so the gods sent a scorpion to kill him, but then they felt bad and placed him in the sky
• Galaxy


  A huge system of gases, dust, and billions of stars

  
• Our Sun is on the edge of the Milky Way Galaxy

  
• Universe


  Everything that exists in space, containing millions of galaxies