INTRODUCTION
For millennia mankind has inhabited the third planet from the sun; the planet that supports life and is know to us as Earth. Although there has been life on Earth for quite sometime, it is only in the past few centuries that man has come to learn about what makes up the interior of this planet.
The English scientist, Isaac Newton, can be seen as a pioneer in regards to learning about the Earth’s interior, as he calculated from his studies of planets and the force of gravity, that the average density of the Earth is twice that of surface rocks and therefore that the Earth's interior must be composed of a much denser material¹. Our knowledge of what's inside the Earth has improved immensely since Newton's time, but his estimate of the density remains essentially unchanged.
So what is this new knowledge of the Earth’s interior?
PRESENT KNOWLEDGE
‘A round sphere with many layers, all varying in thickness, each having it’s own colour and taste…’ this is a description of a gob-stopper and also bares a close resemblance to the internal structure of the Earth; a sphere divided into three layers, differing in density, composition, strength, and state.
The densest of these layers is the core, which is composed largely of metallic iron, with small amounts of nickel and other elements². The less dense mantle then covers this layer, being composed of magnesium and iron silicates. The outermost layer is that of the crust, it has the lowest density of all the layers and can be separated further as its thickness varies greatly from place to place, with the difference being distinguished by land and sea and also its composition. For this reason the core is subdivided into the continental crust (average thickness 45km with a granitic composition) and the oceanic crust (average thickness 8km with a basaltic composition)¹. Similarly the core can also be subdivided, but the difference is not one between compositions but one by physical state. The inner core of the Earth is solid iron; this is because it is under such high pressure, so high that temperature has no bearing on its state. The outer core has a balance between temperature and pressure so it’s iron composition is in the molten state.
Rock strength can also add further categorisation to the Earths interior, bringing in the sphere layers: the mesosphere, asthenosphere, and lithosphere.
in circumference. The outer few miles of lithosphere is made up of rock called crust.
Charles Lyell Charles Lyell was a British lawyer and one of the smartest geologists known at his time. He was known as the author of the Principles of Geology, which helped popularize the theories and concepts of uniformitarianism. The Principles of Geology was the first book written by Lyell and explained the changes in the earth’s surface. He used the research and information in the book as his proof to determine that the earth was over 6,000 years old. The central argument in his book was “the present is the key to the past”, this meant that to find out what happened in the past you had to look at what was happening now.
As he would travel for his work he had to be protected because many people did not like him at the time. Marshall would face slurs and death threats. Why are people being so mean, you may ask, Thurgood Marshall worked for desegregation in all schools. Marshall was gaining his and others’ equality through the law. He took this work very seriously but he still had his time for his fun with his friends at work. He gave credit for those who did work and deserved the credit. He had faith that the Constitution would help bring down segregation. With the 14th amendment, he helped bring down segregation in schools and he won the case of “ Brown vs. Board of Education”. At this time, his wife Buster was diagnosed with cancer and later on February 11, 1955 she passed
When discussing the great heroes of the Civil Rights Movement, or black history in general, Thurgood Marshall is one of the most iconic and key personnel. While the movement towards racial equality is not defined by one person’s actions, the ending technically can. A man of a powerful stature and poise, he was instrumental in ending the legal segregation of the United States. In doing so, it propelled Marshall to become the first African American to be elected a justice of the Supreme Court.
7. Refer to Figure 22-6. What name is given to the core of the modern-day North American continent that formed in the Proterozoic?
Marshall Thurgood has accomplished many achievements throughout his life and made many changes to society throughout it. Before his famous cases he became widely known for winning many cases on discrimination. According to an article he won twenty-nine out of thirty-two cases in courts .In the case of Plessy V Ferguson in 1869,judges ruled that two facilities are allowed to be segregated as long as they are equal, thus creating the term “Separate but Equal”(“Thurgood Marshall”). In 1953 Marshall was battling the Supreme court in the Brown vs Board of Education case, his landmark case.The Court’s decision resulted in an overturn of the Plessy Case phrase of "separate but equal," agreeing that students' self-esteem was harmed by the fact of segregation (Fox 1). Another famous case is the Browder Vs Gayle case. This case ended the segregation of buses all around the world. He won the case ending the Montgomery Boy Buscott. Due to these cases Marshall was widely support by African Americans and many political figures. This allowed him the honor of receiving a position in the supreme court. He was nominated by President Lyndon B Johnson making him the first African American on the Supreme Court (Daniels 1). Marshall Thurgood has achieved many achievements and changed
Although Pluto was discovered in 1930, limited information on the distant planet delayed a realistic understanding of its characteristics. Today Pluto remains the only planet that has not been visited by a spacecraft, yet an increasing amount of information is unfolding about this peculiar planet. The uniqueness of Pluto's orbit, rotational relationship with its satellite, spin axis, and light variations all give the planet a certain appeal.
Once he graduated from law school, Marshall attempted to establish his own practice but wasn’t able because he had no experience and failed to receive any cases. Thurgood then began working for the Baltimore Branch of the National Association the advancement of colored people in 1934. In one of his first cases Marshall defended Donald Murray. He was denied acceptance into University Of Maryland Law. Marshall and Charles Houston won Murray v. Pearson in January 1935. Marshall biggest case as lawyer was the Brown v. Board of Education of Topeka.
( “Brown v. Board of Education”) Marshall was instrumental in ending segregation and became the first African American justice of the Supreme Court. Thurgood was a significant figure in American history because he fought for economic, social, and political justice for minorities as well as helped stop segregation in America’s education system.
It is without a doubt that the most fascinating thing about space is the possibility of life elsewhere beside Earth. It is estimated that the Milky Way Galaxy itself contains about 300 billion stars. Each star contains planets and some planets might even have moons. With these findings, the question is no longer whether life exists elsewhere. The probability that Earth is the only place where life exists in the universe is far too slim. NASA has identified many planets that have similar conditions to Earth but most of these planets are hundreds of light years away so traveling there to find out if there’s any living organism is not easy. Luckily, scientific evidences have pointed out that one of the moons of Jupiter, Europa, could be one of the places where life can exist. If the theories proposed by astronomers about Europa are true, life on Europa might not even be entirely different than life near the bottom of Earth’s oceans.
Research News Planetary Scientists are Seeing the Unseeable Richard A. Kerr Science, New Series, Vol. 235, No. 2 -. 4784. The. Jan. 2, 1987, pp. 113-117. 29-31. The 'Standard' of the 'Standard'. Stable URL:
Core/Interior: The Earth has three layers to it's interior, the inner core, outer core, and mantle. Of these the outer core is thought to be liquid. Like most of the terrestrial planets at birth, the Earth has been molten and undergone some differentiation allowing the heavy material which is consisting mostly of an iron, nickel, and cobalt core making it's density five and a half times the density of water.
Perhaps one of the most interesting features of our fathomless universe are the planets that are classified as gas giants. Huge, turbulent, and distant, the gas giants are some of the most enigmatic features in our Solar System. I have a personal interest to the gas giants and celestial bodies in general. When I was a child, I was fascinated by our Solar System. I read innumerable books about space, and my interests of outer space had been piqued further by other forms of media. Although I held this interest of space, growing up left me with little time to learn about space, and I lost interest for a while. Taking Earth Science in Milpitas High re-invigorated my interests in the celestial bodies. Using this class, I’m now able to focus on learning more about our colossal universe, in particular, the outer planets.
Earth was formed 4.8 billion years ago (3) . It became the home for hazelnuts because it had an atmosphere and environment which allowed for life to prosper in later years. Earth’s surface was once composed of a single landmass, known as Pangaea (1).Over time it was broken up into seven different plates which were free to move as a result of movements in the hot, semi-liquid magma beneath the...
The lithosphere is an open system, which contains all of the cold, hard, solid rock of the planet's crust (surface), the hot semi-solid rock that lies underneath the crust, the hot liquid rock near the center of the planet, and the solid iron core (center) of the planet (Answers.com). On Earth, the lithosphere comprises the crust and the upper part of the mantle. The lithosphere is about sixty miles thick (Lenkeit).