Wait a second!
More handpicked essays just for you.
More handpicked essays just for you.
Physics of stars
Don’t take our word for it - see why 10 million students trust us with their essay needs.
Recommended: Physics of stars
Stars are one of the most widely recognized astronomical objects in the known universe. These celestial bodies are the building blocks of galaxies and their age, composition, and distribution are used to trace their galaxy’s history. Stars are also responsible for the existence of heavy elements such as carbon, nitrogen, oxygen, and iron. These elements are the result of the thermonuclear fusion that takes place in the stars’ cores over millions to trillions of years, making them the most effective and productive nuclear reactors in the the cosmos. In the case of the solar system stars also provide the light and heat required to support life which is a near impossible and extremely rare phenomenon. Stars are extraordinary objects in the entirety …show more content…
This is because Black Dwarfs, unlike black holes, do not cause gravitational lensing that would result in the manipulation of space around them, making them virtually invisible. However, this does not mean that they do not have a gravitational pull, it simply means that their gravity is not strong enough to alter the world around them. However, they are relatively easy to understand “A black dwarf is simply white dwarf that has cooled down to the temperature of the cosmic microwave background [CMB]” (Tate). Once a star has become a White Dwarf it is no longer fusing elements, therefore it has no source of internal energy, and only shines because it is still extremely hot. If a White Dwarf becomes a Black Dwarf at 5°K (-450.67°F), the temperature of the CMB, it would take one quadrillion years, or a one with fifteen zeros after it, (1,000,000,000,000,000) for a newly formed White Dwarf to become a Black Dwarf. White Dwarfs live for such a long time because they only cool via radiation (Tate). Meaning energy is only released by means of particles or waves, unlike an object such as the Earth which releases energy by radiation, convection, and conduction. This extremely slow cooling process is the main reason why Black Dwarfs are so rare and the chances of discovering one in the vastness of the universe are remarkably tiny. For these reasons not a lot is known about Black Dwarfs, but as science advances maybe the world’s knowledge of them will advance
When itBetelgeuse cannot fuse anymore anything over iron, the star will not have enough energy to make heat. Eventually, the core will collapse. When Betelgeuse collapses, it is so strong and powerful that it causes the outer layers to rebound. With the rebound it will have an explosion, which is called a Supernova (Type two). The explosion has so much energy and power that the temperature becomes really hot. The temperature is so hot that it can use the fusion process much heavier than iron. The elements that were given off from the explosion are sent throughout space and are now new nebula. When the Supernova is done, it has left behind a star called a Neutron star. They form when atoms of the core of a dead star are crushed together and the end result produces neutrons. The neutrons are with electrons that are degenerate on the surface. Many Neutron stars have magnetic fields and they give off strong waves of radiation from their poles. These types of Neutron Stars are known as Pulsars.
Brown dwarfs are objects in space that sit between the lines of being a star and a planet. This object is dim and hard to distinguish from low mass stars at the early stages of the dwarf’s life. They are often called failed stars because they start their life the same way as regular stars. However, in some stage, they just didn’t have enough mass gathered to generate the fusion-powered energy of a star. Scientists are certain that brown dwarfs are the missing link between stars and planets but the formations of dwarfs are still a mystery.
A Black Hole is defined as an object in space that is so compact, that has a gravitational pull so powerful, not even light can escape its pull. In most cases Black Holes are formed when a massive star (much larger than our own) undergoes a supernova explosion. When this happens, the star may collapse on its own gravitational pull, thus resulting in a an object with infinitely large density and zero volume. As a result, the escape velocity (the speed required to escape the gravitational pull) becomes even greater than the speed of light, and because nothing can travel faster than the speed of light, nothing can escape a black hole.
We have done a lot of research about space and have learned a lot with the technology we have. One of the main mysteries that we have not understood much is “the hole”. When I say “the hole” I mean the three main ones the black hole, white hole, and the wormhole. Each one is important in their own way, but this paper will be focused on black holes. I will briefly touch on theories that involve time travel, white holes, and wormholes.
The American scientist John Wheeler coined the phrase “black hole” in 1969 to describe a massively compact star with such a strong gravitational field that light cannot escape. When a star’s central reserve of hydrogen is depleted, the star begins to die. Gravity causes the center to contract to higher and higher temperatures, while the outer regions swell up, and the star becomes a red giant. The star then evolves into a white dwarf, where most of its matter is compressed into a sphere roughly the size of Earth. Some stars continue to evolve, and their centers contract to even higher densities and temperatures until their nuclear reserves are exhausted and only their gravitational energy remain. The core then rushes inward while the mantle explodes outward, creating neutron stars in the form of rapidly rotating pulsars. Imploding stars overwhelmed by gravity form black holes, where the core hits infinite density and becomes a singularity (some estimate it at 10^94 times the density of water).
Before I begin to speak about black holes, I will have to explain what the white glowing specks in the sky are. Without a star a black hole could not be formed. In the beginning of a star life a hydrogen is a major part of its development. Stars form from the condensation of clouds of gas that contain hydrogen. Then atoms of the cloud are pulled together by gravity. The energy produced from the cloud is so great when it first collides, that a nuclear reaction occurs. The gasses within the star starts to burn continuously. The hydrogen gas is usually the first type of gas consumed in a star and then other gas elements such as carbon, oxygen, and helium are consumed. This chain reaction of explosions fuels the star for millions or billions of years depending on the amount of gases there are.
A white dwarf uses electron degeneracy pressure to support itself. It is because of the electron degeneracy pressure that white dwarfs have a small size relative to other types of stars.
The Big Bang Theory is one of the most important, and most discussed topics in cosmology today. As such, it encompasses several smaller components that attempt to explain what happened in the moments after creation, and how the universe we know today came from such a fiery, chaotic universe in the wake of the Big Bang. One major component of the Big Bang theory is nucleosynthesis. We know that several stellar phenomena (including stellar fusion and various types of super novae) are responsible for the formation of all heavy elements up through Plutonium, however, after the advent of the Big Bang theory, we needed a way to explain what types of matter were created to form the earliest stars.!
Stars are born in the interstellar clouds of gas and dust called nebulae that are primarily found in the spiral arms of galaxies. These clouds are composed mainly of hydrogen gas but also contain carbon, oxygen and various other elements, but we will see that the carbon and oxygen play a crucial role in star formation so they get special mention. A nebula by itself is not enough to form a star however, and it requires the assistance of some outside force. A close passing star or a shock wave from a supernova or some other event can have just the needed effect. It is the same idea as having a number of marbles on a trampoline and then rolling a larger ball through the middle of them or around the edges. The marbles will conglomerate around the path of the ball, and as more marbles clump together, still more will be attracted. This is essentially what happens during the formation of a star (Stellar Birth, 2004).
A star begins as nothing more than a very light distribution of interstellar gases and dust particles over a distance of a few dozen lightyears. Although there is extremely low pressure existing between stars, this distribution of gas exists instead of a true vacuum. If the density of gas becomes larger than .1 particles per cubic centimeter, the interstellar gas grows unstable. Any small deviation in density, and because it is impossible to have a perfectly even distribution in these clouds this is something that will naturally occur, and the area begins to contract. This happens because between about .1 and 1 particles per cubic centimeter, pressure gains an inverse relationship with density. This causes internal pressure to decrease with increasing density, which because of the higher external pressure, causes the density to continue to increase. This causes the gas in the interstellar medium to spontaneously collect into denser clouds. The denser clouds will contain molecular hydrogen (H2) and interstellar dust particles including carbon compounds, silicates, and small impure ice crystals. Also, within these clouds, there are 2 types of zones. There are H I zones, which contain neutral hydrogen and often have a temperature around 100 Kelvin (K), and there are H II zones, which contain ionized hydrogen and have a temperature around 10,000 K. The ionized hydrogen absorbs ultraviolet light from it’s environment and retransmits it as visible and infrared light. These clouds, visible to the human eye, have been named nebulae. The density in these nebulae is usually about 10 atoms per cubic centimeter. In brighter nebulae, there exists densities of up to several thousand atoms per cubic centimete...
The Big Bang, the alpha of existence for the building blocks of stars, happened approximately fourteen billion years ago. The elements produced by the big bang consisted of hydrogen and helium with trace amounts of lithium. Hydrogen and helium are the essential structure which build stars. Within these early stars, heavier elements were slowly formed through a process known as nucleosynthesis. Nucleosythesis is the process of creating new atomic nuclei from pre-existing nucleons. As the stars expel their contents, be it going supernova, solar winds, or solar explosions, these heavier elements along with other “star stuff” are ejected into the interstellar medium where they will later be recycled into another star. This physical process of galactic recycling is how or solar system's mass came to contain 2% of these heavier elements.
Supernovas are extremely powerful explosions of radiation. A supernova can give off as much energy as a Sun can within its whole life. A star will release most of its material when it undergoes this type of explosion. The explosion of a supernova can also help in creating new stars.
Human fascination with the stars is as ancient as Babylonians and has been suggested to be older than Stonehenge. From “be fruitful and multiply” to “live long and prosper,” the instinct to protect and propagate the species has manifested in religion, art, and the imaginations of countless individuals. As human understanding of space treks out of the fantastical and into the scientific, the realities of traveling through and living in space are becoming clearer. Exploring, investigating, and living in space pose an expansive series of problems. However, the solutions to the problems faced by mankind's desire to reach beyond the horizon, through the night sky, and into the stars are solutions that will help in all areas of life on Earth.
Black holes are the result of the death of a massive star, leaving behind a dense remnant core that eventually collapses to create a gravitational force so strong that nothing, including light, can escape the force. The theory that black holes existed started back in the early 1900s and since then astronomers and scientists have been trying to get a better understanding of them. This phenomenon has been a working progress for astronomers and scientists for many years and as we develop a better understanding of our solar system, the more likely it is to make a significant discovery that can answer some of the most difficult questions about our incredible galaxy and solar system. The more information we are able to acquire about our universe, the more questions we might be able to answer about our existence. With advancements in technology we may be able to see some significant discoveries and insights into the world of black holes.