6.4 Nebulae

• Nebulae

  • Are clouds of dust and gas in space
  • Gases found in it are mostly hydrogen and little amount of helium
  • Particles of gas and dust are very far apart
  • Mostly nebulae are large, even bigger than the solar system
  • Some formed when giant stars explode, sending dust & gas over a wide area
• In Northern Hemisphere

  • Can see Orion nebula which is visible in winter
  • Can see the it without a telescope
• In Southern Hemisphere

  • Can see Carina nebula
  • It is visible without using a telescope
• Stellar Nurseries

  • Is an area in space where stars are formed
  • Stellar = to describe about stars
  • What is nursery?= a place to care for young people, animals or plants. Hence, this case is for young stars

  Some type of nebulae acts as stellar nurseries
• Sterllar Nurseries

  • The dust and gas can start to collapse together under the force of gravity
  • When the mass of dust and gas collects together and becomes larger, the force of gravity pulling inward increases
  • When this force gets larger, the pressure inside the new star also gets larger
  • The high pressure causes heat
  • The heat can cause atoms to react with each other, causing the new star to give out heat and light
  • Some of the young stars are only half mass of the Sun and not reaching the full brightness yet
  • The light from the stars lights up the dust and gas in the cloud