P8 - Space

• life cycle of a star

  • first starts as a nebula a cloud of dust and gas
  • force of gravity pulls the dust and gas together forming a protostar and starts fusion activity
  • hydrogen nuclei fuses with helium nuclei forming a main sequence star which enters a long stable period
  • red supergiant formed when star runs out of hydrogen so it is expanding
  • supernova created by a massive fusion reaction and is the end of a star
  • supernova collapses under its own gravity becoming a black hole or a neutron star
• the solar system

  is all the stuff that orbits our sun
• things included in our solar system

  • planets
  • dwarf planets
  • moons
  • artificial satellites
• the size of an orbit depends on the objects speed
• components of space (small-large) :

  • dwarf planets
  • comets
  • asteroids
  • earths moon
  • planets
  • moons
  • sun
  • solar system
  • galaxy
  • universe
• asteroids are rocky bodies where as comets are icy bodies
• nuclear fission

  splitting a large nucleus into smaller nuclei
• nuclear fusion

  the joining of two small nuclei
• formation of a star

  • a protostar is formed form a cloud of dust
  • gravitational collapse is balanced with fusion
  • forms a main sequence star
• red shift

  is the speed of light is decreasing as the object gets further away from the observer
• Hubble constant

  speed limit of universe expansion