1: basics of earth

Question 1

What is a planet?

Answer 1

International Astronomical Union (IAU) 2006
Official people in charge
Planets must be:
Must be in orbit around the Sun (not around another object)
Must be massive enough to be rounded by its own gravity
Must be a sphere
Must have cleared the neighborhood around its orbit

Question 2

IAU’s Solar System

Answer 2

Sun
Eight planets
Other stuff
Many dwarf planets* and moons
>3 “Dwarf Planets”(not actually considered planets): Ceres, Pluto, Eris
Satellites
Millions of asteroids and comets

Question 3

the big bang

Answer 3

The Big Bang
All matter and energy in the Universe started out as a single infinitesimally small point
It exploded and has been expanding since

Question 4

simple atoms in big bang

Answer 4

Protons
Neutrons
Electrons
H and He
Formed in Big Bang

Question 5

element vs isotope

Answer 5

Element: Unique number of protons in its NUCLEUS
Isotope: Different numbers of neutrons for a given element

Question 6

Stellar nucleosynthesis

Answer 6

Lightest elements (H, He, Li) formed during the Big Bang
Elements up to Fe (atomic number 26) formed in stars
Stellar nucleosynthesis
Elements larger than Fe formed during supernovae

Question 7

Death of a Star

Answer 7

Very heavy elements (atomic number >26) form during supernova explosions
This is the Crab Nebula
Rapidly expanding shell of gas from an explosion whose light reached the Earth in 1054 CE

Question 8

Formation of the solar system

Answer 8

4.6 Ga
Gas and debris (from previous generation stars)
Condenses into protoplanetary disk
Center of the disk ignites into nuclear fusion
Dust in the rings of disk coalesce into planetesimals

Question 9

Planetesimals into planetoids

Answer 9

Dust particles and stony debris accumulate to create a lumpy planetoid
Interior of the planetoid heats up to melting
Allows the body to become spherical
Allows heavy (dense) materials to move to the middle
Differentiation!!!! over time physical and chemical layers of planet seperate

Question 10

Earth’s unique nature

Answer 10

Near circular orbit
Just right size
Just right place
Plate tectonics
Magnetic field
Ozone layer
Axial tilt at 23.4°
Moon
Jupiter

Question 11

Differentiation of Earth’s spheres

Answer 11

(Magnetic field)
Atmosphere
Hydro/Cryosphere
Biosphere
Geosphere/Lithosphere
-Crust
-Mantle
-Core

Question 12

Atmosphere`

Answer 12

air

Question 13

Hydro/cryosphere

Answer 13

ice and water above ground

Question 14

biosphere

Answer 14

plants and animals

Question 15

Geosphere

Answer 15

under everything differentiated by chemical and physical properties
Iron and oxygen followed by magnesium and silicon make up most of the earth’s mass

Question 16

How can scientists determine ANYTHING about the center of the earth

Answer 16

earthquake waves: monitored due to things like the cold war
Earthquakes generate several different types of waves.
P-waves can move through solids and liquids
S-waves can only move through solids
S-wave shadow zone indicates a liquid outer core

Question 17

Earth’s crust: continental

Answer 17

Two kinds of crust
Continental crust
Thicker
Older
Less dense

Question 18

Earth’s crust: oceanic

Answer 18

Oceanic crust
Thinner
Younger
Denser

Question 19

Stretching and mountain building

Answer 19

stretching thins crust, mountain building thickens crust

Question 20

Why are the oceans mostly covering the oceanic crust?

Answer 20

Ocean crust is thinner and denser, so it is always at lower elevations

Question 21

Earth’s crust chemical composition

Answer 21

mostly oxygen (93%), then silicon, aluminum, iron

Question 22

Interior: Mantle and Core

Answer 22

Mantle
Largest layer by thickness
Composed of two sublayers
Upper mantle
Lower mantle
Convection transfers heat from the interior to the surface
Core
Densest layer
Composed of iron-nickel alloy
Composed of two sublayers
Outer core—LIQUID
Inner core–solid

Question 23

what creates the earth’s magnetic field

Answer 23

Convection in the outer core creates Earth’s magnetic field

Question 24

How do we know? about the inner layers of the earth

Answer 24

Pieces of the upper mantle have been dragged up in explosive volcanic eruptions
The density of the earth requires an iron metal core
Some meteorites from the destruction of small planetoids show core/mantle characteristics

Question 25

Two ways of looking at the layers of the world

Answer 25

Chemical properties
-Crust
-Mantle
-Core
Physical properties
-Lithosphere
-Asthenosphere
-Mesosphere
-Outer Core
-Inner Core

Question 26

Layers of the Earth: Physical Properties Version

Answer 26

AS you go down pressure and temperature increase. The differences in states of matter of these payers are decided by whether temp or pressure wins at that spot: increased temp cause liquids increased pressure causes solids:
Lithosphere: Solid
Asthenosphere:
Partially solid, partially liquid
Mesosphere: Solid
Outer Core: liquid
Inner Core: solid

Question 27

Chemical Layers

Answer 27

Crust
-Silicate rocks: Silica and alumina
Mantle
-Silicate rocks: Abundant iron and magnesium
Core
-Iron and nickel

Question 28

Earth-related problems society faces

Answer 28

Climate change
-Global warming
-Rising sea levels
-CO2 emissions
-Melting ice caps
Depletion of natural resources
-Non-renewable energy sources
-Energy shortage
-Decrease in oil
-Deforestation
Pollution
-Water contamination
-Solar panels in landfills
-Industrial waste
-Consumer waste
Fresh water depletion
Droughts