title: Science - Space Year 10 layout: draft categories:

  • Year 10
  • Science tags:
  • Year 10
  • Science
  • Space
  • Review date: 2019-10-25 12:26:00 math: true

Definitions
  • Absolute magnitude: the brightness of an object when viewed from a fixed distance
    • Used to eliminate the brightness differences caused by distance
  • Relative brightness: brightness when viewed from earth
  • Star: A ball of gas held together by gravity
  • Nebula: An interstellar cloud of dust, hydrogen, helium and other ionized gases
  • Solar System: a central sun with its associated planets, asteroids, meteors, satellites (i.e. ,moons), and comets that are “captured” in its orbit.
  • Galaxy: A huge collection of gas, dust, and billions of stars and their solar systems, held together by gravity

Life cycle of a star

Life cycle of a star image

  • Most stars occur in the MAIN SEQUENCE
  • After they run out of Hydrogen to fuse, main sequence stars will expand, turning into a RED GIANT, and will start to fuse Helium
  • Once their Helium supply runs out, the star will expel its outer layers in a PLANETARY NEBULA. At the core of this nebula is the remains of the star: a WHITE DWARF

Hertzsprung-Russell Diagrams

Image from Wikipedia

  • Shows the color vs temperature vs lifespan vs absolute magnitude

Scale of the Universe

  • Interstellar distances are measured in LIGHT YEARS
    • 1 Light Year = about 9.5 trillion km
  • Further distances can also be measured in PARSECS
    • 1 parsec = 3.26 Light Years = 31 trillion km

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Pranav Sharma
Pranav Sharma
Site Owner

Year 12 Student, site owner and developer.

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