At Home in the Universe FINAL

Creation myth

stories and explanations which describe the beginnings of humanity, earth life, and the universe

Common characteristics of creation myths

- the world was created for us

- it is centered on us

- time exists as a framework for human history

- we must keep some kind of link with the sacred aspects of the creation event (balance in the Diné, singing the Song Lines in the Waking time, keeping God's law etc)

Navajo

Thought of the creator made:

light in east

air in west

water in south

earth in north

Earth and Sky deities keep balance

Aboriginal Australians

sleeptime

dream time

waking time

Abrahmaic

Elohhim creation: Genesis 1: sequence of creator's actions

7th day of rest

Garden of Eden: innocence and 'golden' age; parallels Fern Hill

Hinduism

oldest major religion; basis of most religions; polytheistic

Trinity: Brahma, Vishnu, Shiva

Brahma (Hinduism)

Creator

Vishnu (Hinduism)

Preserver or Balancer

most prayed to due to being active in our time of living

Shiva (Hinduism)

destroyer

the restarter of worlds, can be a partial reset

Linear time

Time based on past, present, and future

Cyclic time

The length of time necessary for the completion of a cycle of major deposition or erosion. Cyclic time is one of the three categories in the time-scale of geomorphology.

Why does the length of the day vary throughout the year?

-due to the tilt of Earth's axis of rotation to that of its path around the sun

-Earth's axis is not straight (90º), so the axis is inclined.

What is the month based on?

-natural period related to the motion of the moon

-cycle/beat 2

What is the year based on?

-duration of Earth's orbit around the sun

-cycle/beat 3

What is precession? And how long is it?

the wobble in Earth's rotational axis

-the longer term astronomical cycle ~26,000 years

What is obliquity? And how long is it?

aka Milankovitch cycle

-cyclical movement of Earth orbiting the sun

º eccentricity, axial tilt, and precession

~41,000 years

How do eclipses prove that the Sun and the Moon are different sizes?

-eclipses showed that the moon was illuminated by reflected light

Plato

Mathematic essence; point of origin and then steady

Aristotle

Eternal universe; archetypes

Stoics

cyclic universe and fatal necessity; cosmological gods

Epicureans

Linear universe from golden age

No gods

Direct evidence

Evidence that establishes the existence of a fact that is in question without relying on inference

Gives evidence of events in order but not specific dates

Ex:Kings list

Indirect evidence

...

Antikythera Mechanism

Greek mechanical calculating devise

dated at the end of the second century BCE

1000 years passed before a more complex

machine is known to have been invented

Physical evidence of knowledge at that time

How did we date the pyramids

....

Induction

Generalizations based on observations

Deduction

Explanations based on laws and theories

Falsification

The action of falsifying information or a theory.

Eratosthenes

calculated the circumference of the earth

Determined Earth was round

Determined Sun rays are roughly parallel approaching Earth but strike at different angles because of Earth's curvature

Why did Eratosthenes hypothesized that the Earth was a sphere?

Earth's shadow appears round during a lunar eclipse

Aristarchus

Calculated distance of Earth, Moon, Sun

115:1 ratio

Calculated angles

What lunar event did Aristarchus need to complete his calculations of the distance of the Earth to the Sun?

A first quarter moon

What does the ratio 1:115 describe?

the relationship between the diameter of the Sun/Moon and their distances away from the Earth

How big is the Earth's diameter relative to the Moon's?

The Earth is about 3.5 times bigger than the Moon's

How did Eratosthenes calculate the circumference of the Earth?

Using geometry and the shadows cast by the sun during the solstice

The angle between sun ray and top of column at Alexandria is the same as angle at center of earth subtended by Alexandria and Syene

How did Eratosthenes and Aristarchus contribute to the science community

People didn't accept it for over a 1000 years

Based their views on the Heliocentric Solar System works

How long does it take for light from the Sun to reach Earth?

8 min

What do light years measure?

Distance

Parallax Method

Uses trigonometry to calculate the distance between Earth and relatively close stars

Cephid variable

Used to calculate distance between Earth and relatively distant stars

Relationship between periodicity of a stars' brightness and its luminosity

Varies in brightness

Compares absolute brightness with apparent brightness

Difference between absolute and apparent brightness

Absolute:brightness we could calculate using math

Apparent:brightness we could determine based on what we see

All models of universe

Recollapsing

Critical-expands but stays stagnet

Coasting-continues to expand

Accelerating-rate of expansion increases through time

What is the current "accepted" model of the universe?

Accelerating(Big Bang)

Why is the Accelerating model the most accepted model?

CMB

Brightness of distant supernovas

Blueshift

Doppler shift of an object coming towards us. (Shorter wavelengths of visible light are bluer)

Redshift

shift of light to a longer wavelength as it moves away

Doppler effect

Increase/decrease of waves as the source and observer move toward/away from one another

Appeared to be stretched out as if they were moving away from us(greater red-shift)

Frequency change depending on movement

Cosmic Microwave Background

Electromagnetic radiation left over from Big Bang

Strongest redshift

Age and formation of solar system?

4.5 billion years

How do we know how the solar system formed?

Super novas

Where does our Sun fit in?

How will our universe eventually end?

6 billion years as Sun burns up

Where do heavy elements form?

How did elemental mass influence planet position?

Gravity, atmosphere

Two main types of planets?

Gas planets(made up of volatiles)

Terrestrial Planets(made up of non-volatiles)

Why are the planets located where they are?

What is the asteroid belt?

Small planetary bodies that circle the sun in a belt between the orbits of Mars and Jupiter

How do we use craters to date planets?

Manu craters indicate the planet is old and has gone through many asteroid impacts

How and when did the Moon form?

The moon is at least 4.45 billion years old

How did the seas or Maria form on the Moon? How do we know?

What is a half-life?

the time taken for the radioactivity of a specified isotope to fall to half its original value.

Can we change an element's half-life?

The half-life never changes

Why is Venus' surface so much hotter than Earth's?

It has more carbon dioxide in the atmosphere which causes a runaway greenhouse effect

A newly formed mineral will have...

0 daughter isotopes

Endogenous energy

How has heat energy been transferred from the interior of the planet, where radioisotopic material is concentrated, to the outside

Exogenous energy

How much energy is received by the planet's surface from external sources

What makes a planet habitable?

Perfect distance from Sun

Perfect Mass for its atmosphere

Good geological activity

Differences and similarities between Earth, Venus, and Mars

Earth-more geological activity than other planets

Mars-Extremely cold/extremely low pressure/smaller than other two planets/More impact craters than Venus

Venus-Same size/density as Earth/Same amount of carbon dioxide as Mars/Larger mass in atmosphere than Earth/Extremely hot

Principle of Uniformitarianism

The present is the key to the past

Principle of Original Horizontality

Sedimentary and volcanic rocks are deposited in horizontal layers

Principle of Lateral Continuity

Sediment forms into continuous lateral layers

Layering effect continues until the sediment thins to nothing or terminates at the edge of another layer

Principle of Superposition

Sediment is deposited in upward stacking layers with the oldest layer at the bottom and the youngest layer on the top

Principle of Cross-Cutting Relationships

If a rock layer or fault cuts across another rock layer or fault, then the feature that is cut across must be older

Principle of Inclusion

If a rock contains fragments of another rock, then the included fragments are older than the rock that encloses them

2 main ways this occurs:

Pieces of preexisiting rocks get included as sedimentary particles in sedimentary rocks

Pieces of rock get bombarded with hot magma. These rocks do not melt completely, but instead when the magma cools the preserved bits of rock are visible

Principle of Faunal Succession

Life forms on Earth have evolved in a recognizable order and once extinct, are never seen again

Any two sedimentary layers with exactly the same fossil assemblage must be of the same age

Even if sedimentary rocks are different from different parts of the world, they are time-equivalent if they have the same fossil assemblage

Uncomformity

A contact between two or more rock units where there is a gap in time

What biolological data do we use to understand the first life forms?

What geological data do we use to understand the first life forms?

Why use multiple approaches to understand the first life forms?

What does the faint young Sun tell us about early Earth?

Why are some animals preserved preferentially more than others?

Individuals who happen to have variations better suited to their local, changing environment will preferentially survive to pass on those traits to their offspring

Overtime, these traits will become more abundant in the population, and that population will therefore have evolved

Explain biodiversity

the variety of life in the world or in a particular habitat or ecosystem.

What is a diversity curve?

What are the Big 5?

End-Ordovician, Late Devonian, End-Permian, End Triassic, End-Cretaceous.

What was the biggest of the Big 5?

End Permian

End Ordovician

3rd largest overall, 2nd largest marine extinction

Late Devonian

359 mya, 75% of all species wiped out

End-Permian Extinction

Largest mass extinction which resulted in the disappearance of 90% of all species

End Triassic Extinction

~199 million years ago to 214 million years ago. massive amounts of lava erupted from the mid atlantic rift. led to the break up of pangea. deadly global warming. rocks from eruption found in eastern United States, eastern Brazil, North Africa, and Spain.

End-Cretaceous extinction

Mass extinction, 65 MYO, of 60-80% of the multicellular species alive, including the dinosaurs (except birds). Hypothesized to have resulted from the impact of an asteriod hitting the earth.

What makes a MASS extinction?

The extinction of a large number of species within a small period of time

Brahmanic Day

a "kalpa",

4,320,000,000 human days long