-->

• Asteroids are solid objects which orbit within the Solar System. They are generally made out of rock or metal, although many asteroids are known to contain ice and dust. Nearly all known asteroids originate from a region between Mars and Jupiter called the Asteroid Belt.

  On March 18, 2009, an asteroid measuring 43 feet by 95 feet came within 49,000 miles of the Earth. The asteroid, named 2009 FH, was only discovered two nights prior to its fly by. However, officials say that there was never any real danger of a collision. This marks the second near miss asteroid to come this close to the Earth undetected in the same month.FOX New: Close Call: ... (March 18, 2009)

• Fast Facts

  1. Generally made up of rock and/or metal
  2. Sizes range between 1 and 940 kilometers
  3. There are over 90,000 documented asteroids
  4. Believed to be left over material from the formation of the Solar System
  5. First observed in the 1800s
  6. Name derived from Greek, meaning "star-like"NASA: Solar System Exploration - Asteroids
  7. First asteroid discovered: Ceres
  8. Ceres was later reclassified as a dwarf planet
  9. Most asteroids are found within the main asteroid belt, located between Mars and Jupiter

• Types of Asteroids

  • C-Type
    1. Also known as carbonaceous objects
    2. Carbon-rich, rocky composition
    3. Classify about three-quarters of known asteroids
  • S-Type
    1. Also known as silicaceous objects
    2. Made mostly of Iron-rich rock
    3. Classify about one-sixth of known asteroidsNASA: Solar System Exploration - Asteroids

• Near Misses

  On March 2, 2009, asteroid 2009 DD45 passed at 41,010 miles miles above the earth. The "surprise asteroid" was not identified until February 28, 2009, when it was discovered an image taken at the Siding Spring Observatory in Australia.National Geographic: Surprise Asteroid Buzzed Earth Monday (March 2, 2009)

• Related Mahalo Pages

  Astronomy | NASA | Solar System Bent | Solar Cycle 24 | Comets | Ceres | Dawn (Spacecraft) | Dawn Launch | Dawn Mission | Milky Way | Mystery Illness Strikes After Meteorite Hits Peruvian Villa | Vesta | 99942 Apophis | 2007 WD5 | 2007 TU24

Categories

• View History
• Discuss on the Message Board
• Embed this Page
• Share this page