Week 7 Notes Comets, Meteors, and Asteroids Ch 3, Section 5 Page 104 – 107

I. COMETS a. A __COMET__ is a dirty __SNOWBALL__ about the size of a __MOUNTAIN__ b. Comets are loose collections of __ICE__, __DUST__, and small __ROCKY__ particles. c. Comets orbits are usually very __LONG__ narrow __ELIPSES__

A. A Comet’s Head a. The cloud of __GAS__ and __DUST__ that comes off the head when a comet gets near the __SUN__ is called the __COMA__ b. The __SOLID__ inner core of a comet is called the __NUCLEUS__

B. A Comet’s Tail a. Gas and Dust from a comet’s __HEAD__ streams out to form a __TAIL__ b. Comet means __LONG-HAIRED STAR__ in Greek c. Most comets have __2__ tails: __GAS TAIL__ and __DUST TAIL__ d. The comet’s __TAILS__ point __AWAY__ from the __SUN__ e. A __COMET’S__ tail can be more than __100__ million kilometers long. (62 million miles) BrainPop: Comets (2:49)

C. Origin of Comets a. The __KUIPER BELT__ is a doughnut-shaped region that extends beyond __NEPTUNE’S__ orbit to about __100__ times Earth’s __DISTANCE__ to the sun. b. The __OORT CLOUD__ is a __SPHERICAL__ region that __SURROUNDS__ the Solar System about 1,000 time the distance between __PLUTO__ and the __SUN__

II. ASTERIODS a. Objects in __SPACE__ that are too __SMALL__ and __NUMEROUS__ arec called __ASTEROIDS__ b. __MOST__ asteroids __REVOLVE__ around the sun between the orbits of __MARS__ and __JUPITER__ c. The area between Mars and Jupiter is known as the __ASTEROID BELT__ d. __ASTERIODS__ are thought to be __LEFT-OVER__ parts of the __SOLAR SYSTEM__ that never formed into a __PLANET__ BrainPop: Asteroids (3:38)

III. METEORS a. A __SHOOTING STAR__ is actually called a __METEOR__ b. On average there is a __METEOR__ every __10__ minutes c. A __METEROID__ is a chunk of __ROCK__ or __DUST__ in __SPACE__. Meteoroids come from __COMETS__ or __ASTEROIDS__ d. When a meteoroid enters __EARTH’S__ atmosphere __FRICTION__ with the air creates __HEAT__ and produces a streak of __LIGHT__ in the sky. e. __METEOROIDS__ that are too __BIG__ make it pass the __ATMOSPHERE__ and hit Earth’s surface are called __METEORITES__ f. The __CRATERS__ on the __MOON__ were formed by __METEOROIDS__ Meteor caught on camera : http://www.youtube.com/watch?v=Y66OHiB_p4I (22 seconds) Difference between Comets, Meteors, and Asteroids: http://www.youtube.com/watch?v=kAJHVII3_-0 (1:36)