Chapter 14: Impacts From Space- The Basics Flashcards
Where does earth get all its space debris?
From the asteroid belt
Where is the asteroid belt located?
In between Mars and Jupiter
What are Chondtrite meteorites
They are comprised of primitive material.
-Tiny beadlike spherule called chondrules are contained within
What are NEO’s?
Near earth asteroids/comets who’s orbit intersects with earths or comes really close to it
What are Apollos?
NEO that actually intersect earths orbit
What are Amors?
NEO that intersect the orbit of Mars instead of earth
Where do comets come from?
In an envelope called the Oort Cloud
What the most common form space things come to earth as?
In dust form
What happens when something is travelling at the speed of sound or greater?
It will be accompanied by a sonic boom which is just a violent compression of air
What makes an object slow down in the atmosphere?
The increased atmospheric density and the increased friction
-Causes the temperature to increase, burning the object
What are Aerolites?
Stones that make up 92.8% of all meteorites
What are Primitive Chondrites?
Mostly composed of silictte minerals and contain chondrules
-carbonaceous chondrite have abundant volatile carbon compound concentration and are the most primitive
What are Achondrites?
Chondrites made from silicate minerals similar to terrestrial rock
What are Siderolites?
Stony-irons made from nickel-iron alloy and silicate minerals
What are Siderites?
Irons made from mostly iron+nickle
What are chondrules?
Small spherical objects and have crystallized rapidly from molten or at least partly molten drops
The density of our atmosphere _______ most objects, doing what to them?
Shocking them into smaller bits
What is kinetic energy?
Any moving energy
1/2(m) x (v)^2
What happens to the kinetic energy of an object that comes into contact with the earth?
All of the kinetic energy will turn into heat
What is an Ejecta Blanket?
Quantities of mineral dust thickest near the rim and lighter in colour so craters may be easily identified
What are the 2 types of craters?
Simple and complex
What are some large scale crater identifiers?
Overturned rim
Ejecta Blanket
Breccia
What are Coesite and Stishovite?
High pressure forms of silicate
Coesite is common in the walls of craters and known to form in highly explosive volcanic sites
Stishovite forms only from high pressure impacts
What are Tektites?
Common in surrounding crater soils, spherules made from glass of the same composition as the rocks hit by the space object
