SA1 Earth Sci

Review

where does 90% of all stars fall along

sinous band

blue -
red -

blue - hotter (upper left)
red - cooler (lower right)

True or False
The luminosity of light does not affect the temperature

False - The luminosity INCREASES with the temperature

What are all main-sequence stars composed of?

hydrogen and helium

What fuels all main-sequence stars composed of hydrogen and helium?

hydrogen fusion

Hydrogen fusion is faster when _

stars are HOTTER

Surface area affects _

size and luminance

What makes the stars big and small?

Surface radiation - bigger stars
Gravitational pull - smaller stars

What is the starting phase?

Stellar nebula

When does fusion begins?

when condensing gasses become hot enough

What happens when hydrogen in the core of a mature star is exhausted and hydrogen fusion ends?

gravity compresses the core and the temperature rises

What happens after helium fusion?

The star releases a planetary nebula and then shrinks to a white dwarf

How does one become a super nova?

in more massive stars, enough heat is produced to fuse heavier elements, the iron-rich core then explodes to become a supernova

Traits of a supernova

- neutral star
- black hole

True or False
The remnant of a supernova can contract to become a neutron star

True

True or False
If the mass of a dying star is great enough it collapses into a black hole

True

A large volume of space containing many billons of stars held together by mutual gravitational attraction

Galaxies

Types of Galaxies

- spiral
- barred spiral
- elliptical

What are the 2 well known irregular galaxies named after Ferdinand Magellan

The Large and Small Magellanic Stars

Milky Way

A barred spiral galaxy where our Sun lies, and Stars found in the main disk

Dark Matter

Up to 96% of the universe

2 components of Dark Matter

Dark Mass - 23% of the universe, does not interact with light
Dark energy - 73% of the universe, repulsive force that pushes matter outward

Causes the expansion of the universe to speed up

The repulsive force that pushes matter outward from dark energy

Closed Universe Hypothesis

- Gravitational force of the universe is sufficient
- all galaxies will eventually slow down, reverse direction, fall back to the center, collapse, then explodes again to form a universe

Open Universe Hypothesis

- Gravitational force is not sufficient to stop the expansion
- Galaxies will continue to fly apart forever
- As stars fade and cool, the galaxies will separate into cold void

True or False
The Open Universe Hypothesis is trying to determine whether the universe is open or closed

False - The expanding Universe

True or False
Astronomers learned that the expansion of the universe is decelerating

False - Accelerating

The disturbance that transmits energy from one point to another in periodic motions

Waves

Wavelength

distance between successive waves

1. Wavelength
2. Crest
3. Trough
4. Compression
5. Rarefaction

Frequency

number of waves that passes a point in a given time of interval

What happens when a train moves towards and away from you?

Towards - higher frequency
Away - lower frequency

What is a red shift

moves away, light turns redder, longer wavelength, lower frequency

What is a blue shift

moves towards you, light turns bluer, shorter wavelength,higher frequency

What did Edwin Hubble found

light coming to the earth from all distant galaxies displayed a RED SHIFT bcos of the light coming from nearby the stars

Hubble's Law

Galaxies recede at speed proportional to their distance from the observer

How did Hubble compare the galaxy from a dough and raisin

Raisin -> galaxy
Dough -> space
- as the dough doubles in size, so does the distance within the raisins

Evidences that supports the big bang theory and why

1. Galaxies moving away - because of the cosmological red shifts that results from the expansion of space
2. Abundance of Light Elements - expected ratio of hydrogen to helium arrive the exact number in agreement with the observed abundances
3. Presence of cosmic microwave background radiation - "missing radiation" theory by Arno Penzias and Robert Wilson

Cosmic Microwave Background Radiation

If the universe is initially unimaginably hot, researchers should be able to detect the remnant of that heat

In the cores of such stars, hydrogen atoms are fused together through thermonuclear reactions to make _

helium atoms

True or False
Massive main sequence stars burn up their hydrogen faster than smaller stars

True

Big Bang Theory is the least accepted theory

False - most accepted explanation

Andromeda Galaxy

One out of 40 galaxies included in a galactic cluster called Local Group located in the Milky Way

True or False
99.85% of the mass of our solar system is contained within the Sun

True

True or False
Some planets travel in the same direction, on slightly elliptical orbits

False - ALL

True or False
Most large bodies orbit the Sun in different places

False - Approximately in the SAME place

Define planets

- orbits around the Sun
- nearly round in shape
- has cleared his orbits of other objects

Why is the earth not round?

Because of its rotation - counter clockwise

Which planet rotates clockwise

Venus, Uranus

Why does Venus and Uranus rotate clockwise

because it collided with another celestial body

2 classifications of planets

- terrestrial planets
- gas planets

Terrestrial Planets

- made of materials w high melting point (silicates, iron, nickel)
- rotates slower
- thin/no atmosphere
- higher density
- lower contents of volatiles (hydrogen, helium, noble gasses)

Planets under Gas planets and why

- Jupiter
- Saturn
- Uranus
- Neptune
-> because of the dominance of gasses and it is larger in size

Gas planets

- rotates faster
- thick atmosphere
- lower densities
- fluid interiors rich with hydrogen, helium, and ices (water, ammonia, methane)

Asteroids

objects that orbits the sun but is too small to be considered as a planet

Most asteroids orbit where

between Mars and Jupiter - the asteroid belt

Dirty Snow balls

Comets

Loose collection of rocky materials, dust, water ice, frozen gasses)

Comets

Differentiate meteoroid, meteor, meteorite

Meteoroid - debris that enters the earth's atmosphere (outside)
Meteor - when it reaches the atmosphere
Meteorite - reaches the earth's surface

Dwarf Planets

- orbits around the Sun
- are essentially spherical due to their own gravity
- not large enough to sweep their orbits clear of other debris

Kuiper Belt

- Pluto
- Haumea
- Make Make

Where is the Kuiper belt located?

Lies beyond Neptune

The Kuiper Belt was named after

Gerard Kuiper

Nebular Theory

planets develop from rings of gas and dust surrounding the protosun

True or False
Tiny ice and dust condense in a nebula

true

How does the other atoms attach to these particles in the Nebular Theory

gravity

Why does gravity attach atoms to these particles

Gravity pulls a swirling nebula inward

True or False
The central "bulb" of the disk will become the Sun in the Nebular Theory

True

flattened outer part of the disk where other materials are formed

Protoplanetary disk

What causes concentric rings in the nebular theory

Gravity - it caused the gas, dust, and ice of the disk to separate

Planetesimals

when the dust and gas condenses

Protoplanets

when the planetesimals clumps together

The inner rings become __, outer into __

inner- terrestrial planets
outer rings - giant planets

True or false
Earth is one of six planets orbiting the Sun

False - one out of eight

True or False
Our planet is on the outer edge of the Milky Way

True

Skeleton of our planet

Geosphere

Geosphere

- greek word geo : "ground"
- made up of all the rocks, minerals, landforms, and non living stuff

Biosphere

- includes living things
- bio greek for "life"

Biomes

- region w similar plants, animals, terrains, and climate
- deserts, forests, rainforests, grasslands, wetlands

Hydrosphere

- hydro : water
- all water components
- lake, river, glaciers

differentiate lake, rivers, and glaciers

- lake: large body of water surrounded by land
- river: flowing water that moves towards the sea
- glaciers: large, slow moving, sheet of ice

Atmosphere

- atmos : air
- clouds and all gasses on our planet
- reaches and covers the entire planet

Layers of the atmosphere and define each

- troposphere: lowest, contains most of our air
- stratosphere: absorbs UV rays
- mesosphere: coldest layer, no breathable air
- thermosphere: second highest
- exosphere: highest

Building blocks of minerals

Rocks

How are rocks and minerals possibly economically valuable

Extraction, mining, processing

Igneous Rocks

forms when magma coats and solidifies through crystallization

Differentiate magma and lava

Magma - beneath the earth's surface through volcanic eruptions
Lava - on the earth's surface

Igneous Rocks

- "Ignis": fire because they are formed by volcanic activity through the cooling of lava and magma

Extrusive/volcanic rocks

solidified molten rocks at the surface

Intrusive/plutonic rocks

formed at depth

Characterization of Igneous rocks

Texture and composition

True or False
The rate of cooling strongly influences the crystal size

True
- slow cooling of magma = large crystals
- rapid cooling = small crystals

Types based on texture

1. Phaneritic - large crystals that are clearly visible to the eye
2. Aphanitic - small, cannot be seen by the eye and lens
3. Porphyritic - 2 minerals having large difference in grain size
- large grain: phenocryst
- finer grain: matrix
4. Glossy-textured - non crytalline, no mineral grains

Types based on Chemical Composition

1. Felsic - rocks with light color
- fel - feldspar of the potassium rich variety
- sic - high percentage of silica
2. Mafic - usually dark in color
- ma - magnesium
- fic - iron (latin)
3. Andesitic - light and dark
4. Ultramafic - mostly dark-colored minerals

Sedimentary Rocks

eroded materials are deposited as sediments, will undergo lithification and become compacted and cemented

Lithification

process which transforms into sedimentary rocks

compaction

occurs when files of sediments accumulate and the materials below are compacted by WEIGHT of the overlying layers

Cementation

water that seeps through pore spaces between particles may contain cementing materials which binds particles together

Strata

distinctive characteristics of sedimentary rocks where fossils/imprints of animals that existed are seen

Types of Sedimentary Rocks

1. Detrital - from weathered rocks, basis from the size of particles
2. chemical - from weathered rocks, basis from the chemical composition