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Chapter II: Earth: Its places in the universe- This section will look at the different theories of now the universe

developed

- Stephen Hawking wrote the brilliant essay on the origins of the universe

- He noted that the creation of the universe from a singularity does not

violate any of the laws of physics

- This reinforces the theory that the universe the earth the star and all

planets follow logical, scientific laws.

First, size

- The universe is so incredibly vast in size that it is difficult to comprehend

- Thanks to the recent development of Hubble telescope; scientists are

gaining new insight to the universe and are getting validation for many of

their original theories.

- Because of the magnitude of the distance involved, scientists use the

measure of light year.

- Of course a light year is not a time measurement rather it is a measure

of distance.

- A light year is the distance light travels in a year.

- Light travels at a speed of 300,000 km per second

- In one year, that is approximately 9.5 trillion km (9.51012 km)

- The light that you see from the stars at night was emitted several

hundreds of years ago or more.

- Some of those lights extinguished themselves long before we walked the

earth

- Earth is found in the Milky Way, a spiral galaxy

- This is the name of our galaxy

- Our star is SOL

- There are four types of galaxies

- Spiral, bar spiral, elliptical and irregular

- The Milky Way is a spiral galaxy

- Stars are the central parts of all galaxy

- There are masses of hot gases that emit light and heat

- Stars provide the fuel of all life.

- There are 4 known types of star

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- Our star (Sol) is a normal or average star.

- We will take a closer look at the make-up of later.

Origins of the universe

- The two most popular theories of the origin of the universe are the Big

Bang Theory and the Steady State Theory- Since the universe began many billions year ago, we hypothesize on its

origin using data collected from meteorites, observation of stellar bodies

(astronomy) and the use ofthe Laws of Uniformatarianism

- This allows scientists to make accurate analyses of origin of our universe.

- Pages 21 and 22 discuss the two theories further

- Our solar system is defined by all of the planets, moons, asteroids and

comets that inhabit the gravitational field generated by our sun.

- Our solar system is only one of any that inhibit the galaxy known as theMilky Way.

The origin and the sun and the earth

- The sun's energy comes from nuclear fusion

- The incredible energy produced by the sun provides energy the energy

needed from the earth.

- The breakdown of the sun is as follows.

- The surface is the phosphorus

- The dark spots are sunspots

- The sun acts in many ways like an enormous generator

- The energy generates an electromagnetic field.

- The surface of the sun is in a state of constant and violent action.

- Frequently the sunspots will erupt and send out a solar flare.

- These flares have been known to cause many disruptions of

telecommunication devices on the earth.

-

The rise of computer technology and closed circuits has reduced the effectbut they can still cause problems.

- While the sun began as a reaction of gases and chemicals, the earth's

origin was a little more chaotic.

- Once the sun began its life, it generated an immense gravitational pull on

everything around it.

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- The billion of particles that were floating in space began to coalesce into

larger pieces.

- The large rocks began to generate its own gravitational pull and pull in

other pieces

- These pieces would smash together and build onto the original rock.

- The more particles it attracted the larger it grew.

- Eventually the mass began to form as the spinning of the mass generated

a more circular shape.

- The process is known as accretion

- It explains how the earth began and took shape.

- Once the initial mass was established, the chemical reaction created by the

smashing of the rocks into each other began to create heat.

- The pressure and friction caused by accretion

- Led to the melting of the rock.

- In a liquid state, the rock began to separate according to its components.

- The heavier elements like iron (Fe) began to sink to the center

- The lighter elements like aluminum (Al) floated to the top of the mass

- This separation of elements is known as differentiation.

- The spinning of the earth, the pressure of the gravity field created, and

the chemical reaction caused by the release and combining of chemicals all

combined to create the earth.

- Differentiation explains how the earth was able to develop into the layers

we know today.

- The early earth had a rudimentary atmosphere.

- Since however, the process of differentiation was still ongoing, the earths

internal engine cannot begin.

- The first atmosphere, which was created by the release of the gases

emitted by the chemical reaction of the collision of rock, was soon swept

away by the solar winds

- Soon the surface of the young earth was a violent dance of chemical

reactions.

- Volcanic reaction sent many gases into the new atmosphere.

- By this time the earths' crust had become more solid

- The earths core was spinning and generating a magnetic field that

protected the new atmosphere from the solar winds.

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- The stage was set for life to begin.

- A wonderfully random set of occurrence happened that allowed life to

blossom on the earth.

- The first was the development of the second atmosphere

- Since this atmosphere was not swept away by the solar winds it allowed

for the next stage, the development of free oxygen

- The chemical reaction caused by the smashing of the meteorites released

H2O into the earth

- Soon, vast amounts of water collected in what become our oceans

- They set stage for the growth of algae

- Algae is a primitive form that uses photosynthesis

- The by-product of course is the release of free oxygen.

- The next and most important random act was the location of earth is what

is known as the Goldilocks Zone

- This is known as the CHZ - Continuously Habitable Zone

- That is, the area not too closes to the sun....

- Too hot -> Not to warm from the sun....

- Too cold -> It is the perfect distance to support life

- Mars shares the zone with us

- Ever wonder why Mars does not support life?

- The truth is, it quite [possibly can and may] have even had life in the

past.

- Mars is within the Goldilocks zone

- The engine however stalled

- Today, Mars is a dead planet.