SCIENCE 3RD QUARTER

• Asteroids


  Chunks of rocks or fragments of planetlike material of varying sizes floating in space
• Asteroids


  They don't have ice materials that would melt in turn into a coma or tail
• Asteroids


  The term asteroid comes from the Greek word asterocides meaning "star-like"
• Asteroids


  They are seen when they reflect the light coming from the sun
• Asteroids


  • Mostly found in the region between Mars and Jupiter called the "Asteroid Belt"
  • Smaller asteroids are found in a region closer to the Earth called NEOs or Near-Earth objects
• Groups of Asteroids


  • C-type (rich in carbon)
  • S-type (stony)
  • M-type (metallic)
  • E-type (containing enstatite)
  • V-type (have basaltic and volcanic crust)
  • Trojans (share the same orbit as Jupiter, Mars and other planets)
• Comets


  • Often described as "dirty snowball"
  • Chunk of ice, gas, and dust that orbit the sun in a long, narrow elliptical orbit
  • Famous for its beautiful tail
  • Came from the Greek word kometes meaning "long-haired"
• Parts of a Comet

  • Nucleus (solid part)
  • Coma (halo of gas, ice, and rock coming from the nucleus)
  • Tail (extension of the "halo" and the most visible part)
• Tails of a Comet

  • Ion Tail (result of the interaction of ion particles with the force of the sun)
  • Dust Tail (usually shows the path of the comet)
• Comets


  • Kuiper Belt (donut-shaped region of icy bodies beyond the orbit of Neptune)
  • Oort Cloud (predicted collection of icy objects farther away than everything else in the solar system)
• Short-period comet


  Comets with orbital periods of less than 200 years, believed to come from the Kuiper Belt
• Long-period comet


  Comets with orbital periods of 200 years and more, believed to come from the Oort Cloud
• Meteors


  • Referred to as "shooting star"
  • Rocky space debris that enters the Earth's atmosphere
  • Smaller than asteroids, could be a size of a pebble or a grain of sand
  • Name originated from the Greek word meteoron which literally means "thing high up"
• Meteoroid


  Rocky space debris in the outer space
• Meteor


  Rocky space debris traveling within the Earth's atmosphere
• Meteorite


  Rocky space debris that has successfully landed on the Earth's surface
• Meteors burn up as they pass through the Earth's mesosphere
• Where do meteoroids come from?

  • From asteroids and comets
  • When asteroids collide, the impact causes the disintegration of its materials
  • As a comet travels towards the sun, it leaves fragment or debris along its orbit or path
• Meteor showers


  Happen when a group of meteoroids travels in the same direction at nearly the same speed
• Fireball


  Another term for a very bright meteor, generally brighter than magnitude -4, which is about the same magnitude of the planet Venus in the morning or evening sky
• Bolide


  A special type of fireball which explodes in a bright terminal flash at its end, often with visible fragmentation
• Types of Meteorites


  • Iron Meteorite (made up of mostly nickel and iron)
  • Stony Meteorite (made up of sand-like materials)
  • Stony-iron Meteorite (made up of combined iron and silicates)