Topic 8 - Space Physics

• Orbits

  • Planets orbit stars
  • Dwarf planets orbit stars
  • Moons orbit planets
  • Artificial satellites orbit Earth
• Size of orbit depends on the objects speed
• Redshift

  • Wavelength of light from distant galaxies has increased
  • They have shifted towards the red end of the soectrom
  • This suggests the source is moving away from us
  • Moving very quickly
  • Distant galaxies have greater red shifts than nearer ones, this means they’re moving away faster
  • This shows the universe is expanding
• Big bang

  • All mater confined in a small space
  • It exploded
  • Started expanding, and has continued