Stars are subsequent to planets when we talk about cosmos.
Arranging the objects from largest to smallest dimensions and from most to least massive, in general, the universe comes first then galaxies, then stars, and finally the planets. Each cluster of heavenly objects has distinct characteristics that depicts and separates each group from one another. Planets are the least among the hierarchical assembly of heavenly bodies, made of small stacks of materials that are cold or in the state of cooling effects; while stars have the capacity to generate central energy through synthesis of different nuclear materials like helium, hydrogen and heavier components (Gamow, 2004, p. 73).Unlike stars, planets literally depend its energy generation from phase transitions, decomposition of nuclear elements and mostly from gravitational collapse which is modified by the planet’s dissociation from the central star.
Many planets have developed somewhere else away from any star although they were unknown; they still contribute and provide gravitational force into the Galaxy.Galaxies are bounded by countless structural assemblage of stars. Planets or stars are stabilized by gravitational collapse resulted from gas pressure; whereas, galaxies are established and stabilized by its elemental angular force.
Since the galaxy does not have the capacity to trap radiation for a longer period of time because of too low mass density, the angular momentum brought by the gas which comes from gravitational collapses maintains equilibrium. Galaxies comes in various types and forms. Some have elliptical structure consisting of primordial stars while others have asymmetrical structures made up of numerous gases and young stars (Bundy, 2007, p.
30).Our universe is a mystifying entity for many scientists although its scope and breadth are expanding enormously. The universe is made up of billions of galaxies, stars and planets and until now, there is no strong evidence regarding the notion that the universe will soon come to its end (Kitchin, 1990, p.
111). Stars are enchanting constituent of the universe and they give the impression of being a lasting object from way up above the sky. Technology and advancement in Science has permitted human beings to know further about the stars.Stars have dawn and they are born.
They exist in a definite time frame depending on their dimension or mass (Brunier and Dunlop, 1999, p. 39). Stars expires and die in due time when all their gases were used up. A star’s existence is calculated like a normal human life. There are certain stages that each star undergoes that include stellar birth, maturation and transition. Similar to life cycle of living things on earth, stars grow up; they count years before they reach their end. Nuclear fusion activates the energy that causes star to remain hot for billion years of its existence.
All stars commence life with the same pattern but nuclear fusion modifies the changes and the transformation. Such changes because of nuclear fusion may lead a star to go through forceful changes; whereas, supernova is the most powerful one (Ratcliffe, 2007, p. 175).The space may look empty, but in fact, it is packed with thinly shared out dust and gas which are identified as interstellar medium.
The atoms of this gas are made up of hydrogen and gas atoms are more likely about centimeter away. The dusts are in microscopic size and basically, they are made up of silicon and carbon. When gas and dust mixed up, they form a big cloud known as nebula. This is where stars are born. Moreover, stars are made up of gas and dust. An example of this is the sun which was born from a nebula just about 5 billion years in the past.Huge clouds of gas and dust in the space are the starting point of new stars and they are mainly composed of helium and hydrogen.
These clouds tend to shrivel and happen to become warmer due to gravity.The temperature inside gets higher when the body of this massive packed of gas and dust starts to breakdown because of its own gravity. As soon as the temperature reached its highest point in several thousand degrees, electrons of hydrogen molecules are stripped.
It caused ionization generating hydrogen molecules to become single protons (Hansen, et. al., 2004, p. 296). Powerful reaction of gas and the temperature increase keeps going on until the star’s temperature arrive at about 10,000,000 degrees Celsius. A certain process called proton-proton reaction takes place during nuclear fusion. Proton-proton reaction is the conversion of four protons that joined together to form and converted into neutrons, the phase where some parts of the star are vanished and transformed into an energy that stabilizes the gravity at some point (Hansen, et. al.
, 2004, p. 296).Several reactions transpire during the process of formation of the star subsequently to achieve life.
It needs to accomplish and sustain equilibrium from the gravity of atoms heaving towards the center in addition to the gas pressure thrusting away the light and heat from the center. To achieve and maintain the stability during this process is very hard and whenever a star can no longer sustain the equilibrium, it expires.Life Stages of StarsProtostars Protostar is the earliest phase of maturity of a star. The product of massive gravitational collapse and nuclear fusion of gleaming clouds comprises of interstellar dust and gas (Zeilik, 2002, p. 317).
As a result of continuous contraction of clouds that are way too hot, a glowing protostar is born and this stage will approximately lasts up to 50 million years if there is sufficient gravitational collapse and if the high temperature remains.Dramatic changes in its brightness and warmness continues until it survive to become a full grown star although it is not nearly as hot as the sun until it reaches its maturity as a star.Bright Star At this point, when a protostar stops from reduction in its size, this is the indication that a star is born. The core extends to come up with an excessive temperature that allows the core of the star to continuously increase causing fusion of small atomic nuclei to generate a larger one.
A star in this stage emits and releases energy that can be felt in the form of heat and light similar to the one that comes from the sun. Fusion in a star will go on for approximately 90 percent of its existence however it may not last for a life time. Compared to human’s life span, the first 30 million years of a protostar is similar to early childhood or formative years ranging from birth to age of four. The next 10 billion years of nuclear fusion as a bright star is like the maturity stage or the time of youth in human life cycle that extended from age of 4 to the latter years of 76. The final stage is the old age where stars grows larger and becomes reddish in color, the reason why it is called red giant (Bova, 2002, p. 382).Red Giants Lack of external flow from the star’s focal point drives the gravity to crowd and compress the core to make it grow less its previous size.
The core gives off heat while releasing vast amount of energy that transmit great quantity of hydrogen gas outside its surface (Krumenaker, 2005, p. 87).At this stage, the star starts to grow to become an enormous and even brighter. When the temperature drops, the star becomes red in color. Red giants are visible in globular cluster that spreads up to one million stars that is moving all together in the space.
White Dwarfs When the stars starts to cool off and the temperature plummet the outer gas layer tends to stretch out. This process causes the gas to spread out in all directions far from the body of the star. Stars in this phase do not emit energy and light that’s why they are called white dwarfs plus they start to collapse little by little. Milky Way Galaxy and Stars Milky Way Galaxy is much known for its band of light crossing the sky. Milky Way Galaxy is a huge collection made up of billions of stars, planets, gas and dust. Scientists believe that the universe and galaxies were formed because of gas reactions due to gravity and forces that drive heavenly bodies that comprises such to pull or push away from one another.ReferencesBova, B.
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