Tuesday, February 21, 2012

First Civilization Part 1

Civilization1

Introduction:

  I have been thinking about this subject for some time to see if I could get the idea that I had in at least partial fact..   If you are not present to an event in history you really don’t know the complete truth because you were not a witness of the event in question (the tree story), or it is a story that has been around for a while and there are different versions and embellishments that have become part of the history- an example is the big bang.  This theory is only that- a theory just like evolution it is a theory and nothing more. Neither one are facts but  are scientific assumptions based on the evidence or remains from the past.  Scientists are not sure how our solar system came into existence, this is one of the reasons why there is so much interest in exoplanets and their stars.  That alone should pose a significant problem, but some people think they have all the answers.  This story considers these issues and some of the theories that I believe could to be possible.  There is not a great amount of information that can be used to tell this story.  This story is composed of many different parts that are designed to present an overall theory I have in mind (and not a complete fact either). My sources come from Wikipedia and Google Earth and sources derived from them.
ALaudun

Chapter 1

The Sun was formed about 4.57 billion years ago when a hydrogen molecular cloud collapsed.
Cone nebula with star formming gas
A molecular star forming cloud
Solar formation is dated in two ways: the Sun's current main sequence age, determined by using computer models of stellar evolution and nucleocosmochronology, the sun is thought to be about 4.57 billion years old. This is in close accord with the radiometric date of the oldest Solar System material, at 4.567 billion years ago.  This was the beginning of what is known as the Hadean Eon. The first time period in Earth’s history.
The Sun is a Population I, or heavy element-rich star.   Some think the formation of the Sun may have been triggered by shockwaves from one or more nearby supernovae. This is suggested by a high abundance of heavy elements in the Solar System, such as gold and uranium, relative to the abundances of these elements in so-called Population II (heavy element-poor) stars. These elements could most plausibly have been produced by endergonic nuclear reactions during a supernova, or by transmutation through neutron absorption inside a massive second-generation star.
The formation of a star begins with a gravitational instability inside a molecular cloud, often triggered by shock waves from massive explosions from a nearby supernova or the collision of two galaxies (as in a starburst galaxy).
Supernova type 1a
Supernova Type 1a
Once a region reaches a sufficient density of matter to satisfy the criteria for instability, it begins to collapse under its own gravitational force. As the cloud collapses, individual conglomerations of dense dust and gas form what are known as Bok globules.


Bok Gloabules
Bok Globules

As a globule collapses and the density increases, the gravitational energy is converted into heat and the temperature rises. When the protostellar cloud has approximately reached the stable condition of hydrostatic equilibrium, a protostar forms at the core. These pre–main sequence stars are often surrounded by a Protoplanetary disk.
proto star inside Blok globule
Proto Star inside Bok Globule
Early stars of less than two solar masses like our Sun are called T Tauri stars, while those with greater mass are Herbig Age/Be stars.
T Tuari star with accretion disk.
T Tauri Star inside Accretion Disk
Theoretical models of the Sun's development suggest that between 3.8 to 2.5 billion years ago, during the Late Hadean or Early Archean Eon, the Sun after coming into existence began to put out more heat and radiation than now. The Earth would not have been able to sustain liquid water on the surface, and thus life should not have been able to develop at that time. Stars spend about 90% of their lifetime fusing hydrogen to produce helium in high-temperature and high-pressure reactions near the core. Such stars are said to be on the main sequence and are called dwarf stars. Starting at zero-age main sequence, the proportion of helium in a star's core will steadily increase. Consequently, in order to maintain the required rate of nuclear fusion at the core, the star will slowly increase in temperature and luminosity–the Sun, for example, is estimated to have increased in luminosity quickly and was brighter than it is today.  Because not all stars act in the same way. Some would disagree with this theory, but it is just like everything else when it is young and new it works more efficiently than when it becomes old. Therefore, the bright luminosity of the sun at this time was greater than now.
The_sun
The Early Sun
The energy produced by stars, as a by-product of nuclear fusion, radiates into space as both electromagnetic radiation and particle radiation. The particle radiation emitted by a star is manifested as the stellar wind, which exists as a steady stream of electrically charged particles, such as free protons, alpha particles, and beta particles, emanating from the star's outer layers with a steady stream of neutrinos emanating from the star's core. The stellar wind or solar wind will play very important part of this story.

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