Physical Geology Test 1

Jean Bernard Leon Foucault(1819-1868)

French physicist; found evidence that the Earth spins on its axis by using a pedulum

Cosmology

The study of the structure and evolution of the Universe

Which model did Ptolemy use? (100-170CE)

Geocentric Model

Which model did Nicolaus Copernicus use? (1473-1543)

Heliocentric Model

Galileo's telescopic observations contradicted?

the geocentric hypothesis.

Who used their laws of motion and gravity to show why planetary orbits are elliptical?

Isaac Newton

Who calcualted the cirumference of Earth?

The Greek Astronomer Era in Alexandria, Egypt

What is the circumference of the Earth found by Astronomer Era?

39300 km (24,421 miles)

What is the actusl circumference of Earth?

40,008 km

What is the actual average distance from Earth to the Moon?

381,555 km

What is the distance between the Sun and Earth?

149,600,000 km (93,000,000 miles)

When was the nearest star, Alpha Centauri, found?

1838

How close is Alpha Centauri (nearest star to Earth)?

40.85 trillion km away

What is a light year?

The distance that light travels in one Earth year, equals about 9.5 trillion km (unit of distance, not time)

What is the speed of light (in miles)?

186,000 miles per second

Alpha Centauri is 4.3 light years away, so how old is the light that we see from the star?

4.3 years

What is the edge of the visible Universe?

Lies 13 billion light years away

Gravity pulls stars into \_____

Galaxies

How many stars are in the MIlky Way?

over 300 billion stars

What is the nearest galaxy to our?

Andromeda (2.2 million light years away)

What is the Doppler effect?

The change in frequency of a wave, when the sources moves relaative to the observer

What is an example of the Doppler Effect?

A moving train; As it moves away from you the frequency is shorter, wavelength longer. As it moves towards you the frequency is higher, wavelength shorter.

What is the Doppler Shift?

As things move away from us, the light is red shifted; As things move towards us, the light is blue shifted

What did Edwin Hubble observe when looking at the light from distant galaxies?

There was a red shift, meaning the universe is expanding away from us

What is the Expanding Universe Theory?

All distant galaxies are moving rapidly away from us. (ex: chocolate chips in bread, while the bread bakes the chocolate chips spread out) WE ARE NOT IN THE CENTER OF THE EXPANSION

How did the Universe form?

The Big Bang is the widely accepted theory

When was the Big Bang?

13\.7 biillion years ago (Big Bang)

What did the collapsed smaller galaxies form during the Big Bang?

The first stars

What are Protogalaxies?

Galaxies that have no significant amounts of any elements besides H and He

What are the 3 lines of evidence that tells us the age of the Universe?

1. Disovery of the expanding universe
2. Modeling formation of elements
3. Star evolution

Recent work suggests that the rate of expansion has changed as time has passed. True or False?

True, it is expanding quicker

How are heavier elements created?

By thermonuclear fusion reactions in stars

What are Coronal Mass Ejections (CME)?

It is when the Sun send billions of tons of solar patricles into space and spread by stellar winds; It can reach Earth 1 to 3 days and affect electronic systems

When were small atoms (H and He) formed?

During Big Bang

When were larger atoms form?

Larger atoms are formed in stars and the largest are formed during explosions of stars

How large is the Milky Way?

Over 100,000 light years across

How many galaxies are there in our visible Universe?

Over 100 billion galaxies

When was the Milky Way formed?

13.7 Billion Years ago

What kind of galaxy is the Milky Way?

Spiral Shaped Galaxy; discs spins due to conservation of angular momentum

When was our solar system completed?

4.5 billion years ago

What is a nebula?

Interstellar clouds of dust and gases

What are nebulas mainly made of?

Mostly H and He

What is the Nebular Hypothesis?

That solar systems start as nebulas byt then condense to become planets

The farther the planet is from the sun,

the less dense it is

What are Chondrites?

Stony meteorites that provide info about the origin and age of the solar system

How old is Earth?

4.54 Ga or Billion years ago

What is a heliosphere?

It is the region of space where solar wind has a significant influence; It encompasses the entire solar system

What is the Kuiper Belt?

A disc-shaped region of icy bodies- includes the dwarf planets and comets that are beyond the orbit of Neptune

Which 4 planets have mountains, valleys, and plains?

Mars, Earth, Venus, and Mercury

What is the order of the planets?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

Earth is the only planet that has distinct continents and ocean basins

continents and ocean basins

The Earth's magnetic field is a dipole. True or False?

True because it has North and South poles

What is the dynamo theory?

The magnetic field of Earth is caused by the motion of Earth's iron outer core

How much does the inner core grow in radius each year?

1 mm

Who proposed the model of dynamo theory?

Walter M. Elsasser in the 1940s

What is the magnetosphere?

The region of Earth's magnetic field shaped by the solar wind.

How is the magnetosphere formed?

By the interaction of solar wind and Earth's magnetic field which makes it teardrop pointing away from the sun

What does the magnetosphere deflect?

Deflects Sol Wind, shield against lethal radiation

What are the Van Allen Belts?

Belts of trapped particles that protect life on Earth from dangerous radiation

What are the Van Allen Belts made up of?

Made of solar wind particles and cosmic rays

What makes up Earth's atmosphere?

Nitrogen(78%) and Oxygen(21%) other gases(1%)

The density and air pressure of gases increase towards..

The Surface

Atmospheric pressure is alsso called \_________

Barometric pressure

What is the lithosphere?

All of Earth's rock and sediment

What is the hydrosphere?

The water on the Earth including both surface and ground water

What is the cryosphere?

All frozen water on earth (snow, ice, ice caps, etc.

What is the biosphere?

The planet's living organisms plus the abiotic (nonliving) parts they interact with

How was the Earth dated?

Used radioactive isotopes

How was Early Earth formed?

it is formed by accretion

How was Molten Earth formed?

Heat from impacts and radioactive decay remelt most of the Earth

How was Differentiated Earth?

Dense metals pulled toward the center as lighter, low-density minerals 'floated' outward to surface. Outgassing during melts creates the atmosphere and oceans.

What was the surface of Early Earth like?

The surface was hot, lack of liquid water, lacked modern atmosphere. Inhospitable

What was the 1st early atmosphere like?

Mostly made of H and He, no magnetic field

What was the 2nd early atmosphere like?

Atmosphere is similar to modern volcanic gases (greenhouse gases). Only missing Oxygen

Todays atmosphere has how much oxygen?

21% oxygen

How do we know that the 2nd early atmosphere had no free oxygen?

Rocks of this age contain Pyrite and Uraninite sediments which only form in non-oxidizing environments

What is bulk earth made up of?

Fe, O, Si, Mg

What is bulk earth?

Proportions of elements by mass

What are the Earth's layers?

asthCrust, mantle, liquid iron outer core, solid iron inner core

Who is the father of modern geology?

James Hutton (1726-1797)

What is the principle of Uniformitarism?

The process we see in action on Earth today have worked much the same way throughout the geologic past

What is the Inner core mainly made up of?

Iron and Nickel

What is the Mantle mainly made of?

Iron and Magnesium

What is the crust mainly made of?

Oxygen and Silicon

Temperature and pressure _____ as we go into Earth

increase

Much of Earth's mass is concentrated where?

close to the center

What is Earth's density?

5.5 g/cm^3

What is the average density of crustal rocks like granite and basalt?

2.2-2.5 g/cm^3

Earthquake waves travel at different velocities and through?

different materials

What is the continental crust made of?

Granite

What is the Oceanic crust made of?

Basalt

What is a major component of volcanic gas?

water

When was the 1st evidence of life found?

3.5-4 billion years ago

What do Cyano-bacteria and Stromatolites do?

Photosynthesizes to provide oxygen for more advanced life forms.

When did milti celled organisms appear?

1 billion years ago

At the dawn of agriculture (8000 BC) what was the population of the world?

5 million

When did the Human population reach 1 billion?

1818

How many years did it take for the human population to reach the next billion (2 billion)?

It took 109 years to reach 2 billion in 1927.

How many years did it take for the human population to reach the next billion (3 billion)?

It took 33 years to reach 3 billion in 1960

How many years did it take for the human population to reach the next billion (4 billion)?

It took 14 years to reach 4 billion in 1974