This document discusses comets, asteroids, and meteors. It explains that comets are dirty snowballs that develop comas and tails as they near the sun due to melting ice. Comets originate from the Kuiper Belt outside Neptune and the distant Oort Cloud. Famous comets include Halley's Comet and Shoemaker Levy 9. Asteroids are large rocks that orbit between Mars and Jupiter, ranging in size from under 1 km to 300 km. Ceres, Pallas, and Vesta are famous asteroids. Meteors are small chunks of dust or rock from comets or asteroids that appear as streaks of light in the night sky, sometimes leaving meteorites if they reach the ground.

1. Stuff in Space6th Grade Science

2. Comets (Long haired star – Greek)What are they?Dirty snowballsSize?MountainOrbit?Large ellipses

3. CometsComaCloser to sun the comets ice meltsGas and dust reflect sunlightNucleus is dense centerTailRapid melting when close to sunPoints away from sun

4. CometsOriginKuiper BeltOutside Neptune’s orbitExtends for 100 A.U.

5. CometsOriginOort CloudBeyond PlutoExtends for 1,000 A.U. in all directions

6. CometFamousHalley’sVisible without telescopeReturns every 75 yearsShoemaker Levy 9Slammed into Jupiter 1994

7. AsteroidsWhat are they?Large rocksSize?< 1 Km to 300 KmOrbitBetween Mars and JupiterNumbers100,000 objects known

8. AsteroidsFamousCeres (dwarf planet)Pallas Vesta

9. MeteorsWhat?A small chunk of dust or rockWhere?Comet or Asteroid pieceAppearance?Streak of light in night sky (shooting star)Meterorites (remains that hit ground)