ES-LEARNING-HANDOUT-WK1 (1).pdf

UNIT Earth’s Origin and I Composition LEARNING OVERVIEW Hey! If I ask you the question: “what is the biggest question in our lives?” What would be your answer? Answering this question will really work up your mind, but being realistic, I...

UNIT Earth’s Origin and I Composition LEARNING OVERVIEW Hey! If I ask you the question: “what is the biggest question in our lives?” What would be your answer? Answering this question will really work up your mind, but being realistic, I think the biggest question in our lives is “how did the Universe begin?” it’s pretty accurate since we are looking for the “biggest”, no pun intended. In this lesson, I would like to talk about the biggest question in our lives that I have in my mind. Please join me in exploring the interesting works of noble scientists who studied the origin of the universe. Let us talk about EARTH SCIENCES.  Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical and chemical constitution of the Earth and its atmosphere. Earth science can be considered to be a branch of planetary science, but with a much older history. Earth science encompasses four main branches of study, the lithosphere, the hydrosphere, the atmosphere, and the biosphere, each of which is further broken down into more specialized fields. There are both reductionist and holistic approaches to Earth sciences. It is also the study of Earth and its neighbors in space. Some Earth scientists use their knowledge of the planet to locate and develop energy and mineral resources. Others study the impact of human activity on Earth's environment, and design methods to protect the planet. Some use their knowledge about earth processes such as volcanoes, earthquakes, and hurricanes to plan communities that will not expose people to these dangerous events. Chapter 1: The Origin and Structure of Earth LEARNING OBJECTIVES In this lesson, you will be able to: 1. describe the historical development of theories that explain the origin of the universe; 2. compare the different hypotheses explaining the origin of the Solar System; 3. describe the characteristics of Earth that are necessary to support life; and 4. explain that the Earth consists of four subsystems, across whose boundaries matter and energy flow. 1. Why do theories on the origin and structure of Earth change? 2. How does Earth support the different forms of life? 3. How important are Earth’s system? Lesson 1.1 THEORIES ON THE ORIGIN OF THE UNIVERSE Origin of the Universe - Theism vs. Atheism In general, theists attribute the origin of the universe to some sort of transcendent, intelligent Designer. Atheists envision a natural, undirected process by which universes spring into existence spontaneously. Prior to the 20th century most atheists believed the universe was eternal. This changed however as discoveries throughout the 20th Century rendered that view untenable. Einstein’s theory of gravity (which has been thoroughly validated by extensive experimental confirmation) and Hubble’s astronomical observations preclude an eternal universe. We now know beyond a reasonable doubt that the universe began at some point in the finite past. Now we understand that there are only two legitimate options for the origin of the universe: (1) Someone made the universe (DIVINE CREATION THEORY), or (2) The universe made itself (BIG BANG THEORY). In an effort to make sense of the universe, humans use religion, traditions, philosophy, and science to describe its origin and structure. There are stories and beliefs passed on from one generation to another, and there are hypotheses and theories that are continuously tested and challenged through the scientific method. Humankind's most recent understanding of the universe is built upon previous knowledge and enhanced by integrating data acquired from latest technologies. DIVINE CREATION THEORY The divine creation theory, or Creationism, is the belief that a divine being is responsible for the creation of life from nothing. There are several religions that are generally considered Creationist, but many modern believers of divine creation believe that science and faith can walk hand in hand. This theory can be narrowed down further between those who differ on their opinion of the role of the creator past the initial creation of life. The standard divine creation theory has several different views. There are those that believe in religious texts, which depict the creation of the Earth as a literal event. Other schools of thought among Creationists state that it was not a literal time period, but more like stages that the divine went through to create the world. The Creationists who follow this train of thought also feel that science is correct in its dating of the Earth and the universe. Many Creationists believe that while divine creation occurred, evolution was also a part of the creation process. The different schools of thought inside the divine creation theory all agree on the fact that a divine being created all life as an act of free will, but past that the differences become numerous.  RIGVEDA THEORY The Hindu text Rigveda describes the universe as an oscillating universe in which a "cosmic egg" or Brahmanda containing the whole universe including the sun, moon, planets, and space- expanded out of a single concentrated point called Bindu and will eventually collapse again. ❖ From the fifth century to third century BCE, the Greek philosophers would present their own description of the universe. o Anaxagoras believed in a primordial universe and explained that the original state of the cosmos was a primordial mixture of all its ingredients which existed in infinitesimally small fragments of themselves. This mixture was not entirely uniform; some ingredients were present in higher concentrations than others, and the distribution of these ingredients varies from place to place. At some point in time, this mixture was set in motion by the action of the "nous" or mind. A whirling motion sifted and separated the ingredients, ultimately producing the cosmos of separated material objects with different properties that can be seen today.  ATOMIC UNIVERSE ❖ Greek philosophers Leucippus and Democritus believed in an atomic universe. They held that the universe was composed of very small, indivisible, and indestructible atoms. All of reality and all the objects in the universe are composed of different arrangements of these eternal atoms and an infinite void in which the atoms form different combinations and shapes. The Stoic philosophers also believed that the universe is like a giant living body, with the sun and the stars as the most important parts to which everything else was interconnected. ❖ The famous Greek philosophers Aristotle and Ptolemy proposed a geocentric universe where Earth stayed motionless in the heavens, and everything was revolving around it. This would later contradict other philosophers' views, most notably, astronomer Nicolaus Copernicus' in 1543 with his theory of heliocentrism. Geocentric universe- Earth at the center of the solar system. Heliocentric universe- Sun at the center of the solar system. ❖ In 1687, Sir Isaac Newton described the universe as a static, steady-state, infinite universe. In his description of the universe, matter on a large scale is uniformly distributed, and the universe is gravitationally balanced but essentially unstable. ❖ French philosopher Rene Descartes outlined a Cartesian vortex model of the universe with many of the characteristics of Newton's static, infinite universe. According to Descartes, the vacuum of space was not empty at all but was filled with matter that swirled around in large and small vortices. His model involved a system of huge swirling whirlpools of fine matter, producing what would later be called gravitational effects. ❖ A model of the universe assumed by Albert Einstein was no different from Newton's in that it was a static, dynamically stable universe, which was neither expanding nor contracting. He added a cosmological constant to his general theory of relativity equations to counteract the dynamic effects of gravity, which would have caused the universe to collapse. He would later abandon this part of the theory when, in 1929, American astronomer Edwin Hubble showed that the universe was not static. Modern Theories on the Origin of the Universe Modern theories on the origin of the universe were a synthesis of the past observations, theories. and laws, as well as new understanding of mass, energy, and relativity. The invention of new types of telescopes and sensors, which extended humankind's ability to observe the farther regions of the universe, were vital in the development of these modern theories.  MODERN THEORIES ON THE ORIGIN OF THE UNIVERSE THE BIG BANG THEORY How and when did the universe begin? No other scientific question is more fundamental or provokes such spirited debate among researchers. After all, no one was around when the universe began, so who can say what really happened? The best that scientists can do is work out the most foolproof theory, backed up by observations of the universe. The trouble is, so far, no one has come up with an absolutely indisputable explanation of how the cosmos came to b The Big Bang Since the early part of the 1900s, one explanation of the origin and fate of the universe, the Big Bang theory, has dominated the discussion. Proponents of the Big Bang maintain that, between 13 billion and 15 billion years ago, all the matter and energy in the known cosmos was crammed into a tiny, compact point. In fact, according to this theory, matter and energy back then were the same thing, and it was impossible to distinguish one from the other. According to the theory, matter was not present at the beginning of time; there was only pure energy compressed in a single point called singularity. Adherents of the Big Bang believe that this small but incredibly dense point of primitive matter/energy exploded. Within seconds the fireball ejected matter/energy at velocities approaching the speed of light. At some later time maybe seconds later, maybe years later—energy and matter began to split apart and become separate entities. All of the different elements in the universe today developed from what spewed out of this original explosion.  Big Bang theorists claim that all of the galaxies, stars, and planets still retain the explosive motion of the moment of creation and are moving away from each other at great speed. This supposition came from an unusual finding about our neighboring galaxies. In 1929 astronomer Edwin Hubble, working at the Mount Wilson Observatory in California, announced that all of the galaxies he had observed were receding from us, and from each other, at speeds of up to several thousand miles per second. EVIDENCE THAT SUPPORTS BIG BANG THEORY The Redshift To clock the speeds of these galaxies, Hubble took advantage of the Doppler effect. This phenomenon occurs when a source of waves, such as light or sound, is moving with respect to an observer or listener. If the source of sound or light is moving toward you, you perceive the waves as rising in frequency: sound becomes higher in pitch, whereas light becomes shifted toward the blue end of the visible spectrum. If the source is moving away from you, the waves drop in frequency: sound becomes lower in pitch, and light tends to shift toward the red end of the spectrum. You may have noticed the Doppler effect when you listen to an ambulance siren: the sound rises in pitch as the vehicle approaches, and falls in pitch as the vehicle races a To examine the light from the galaxies, Hubble used a spectroscope, a device that analyzes the different frequencies present in light. He discovered that the light from galaxies far off in space was shifted down toward the red end of the spectrum. Where in the sky each galaxy lay didn't matter—all were redshifted. Hubble explained this shift by concluding that the galaxies were in motion, whizzing away from Earth. The greater the redshift, Hubble assumed, the greater the galaxy's speed. Some galaxies showed just a slight redshift. But light from others was shifted far past red into the infrared, even down into microwaves. Fainter, more distant galaxies seemed to have the greatest red shifts, meaning they were traveling fastest of all.  An Expanding Universe So if all the galaxies are moving away from Earth, does that mean Earth is at the center of the universe? The very vortex of the Big Bang? At first glance, it would seem so. But astrophysicists use a clever analogy to explain why it isn't. Imagine the universe as a cake full of raisins sitting in an oven. As the cake is baked and rises, it expands. The raisins inside begin to spread apart from each other. If you could select one raisin from which to look at the others, you'd notice that they were all moving away from your special raisin. It wouldn't matter which raisin you picked, because all the raisins are getting farther apart from each other as the cake expands. What's more, the raisins farthest away would be moving away the fastest, because there'd be more cake to expand between your raisin and these distant ones. That's how it is with the universe, say Big Bang theorists. Since the Big Bang explosion, they reason, the universe has been expanding. Space itself is expanding, just as the cake expanded between the raisins in their analogy. No matter whether you're looking from Earth or from an alien planet billions of miles away, all other galaxies are moving away from you as space expands. Galaxies farther from you move faster away from you, because there's more space expanding between you and those galaxies. That's how Big Bang theorists explain why light from the more distant galaxies is shifted farther to the red end of the spectrum. In fact, most astronomers now use this rule, known as Hubble's law, to measure the distance of an object from Earth—the bigger the redshift, the more distant the object. In 1965 two scientists made a blockbuster discovery that solidified the Big Bang theory. Arno Penzias and Robert Wilson of Bell Telephone Laboratories detected faint microwave radiation that came from all points of the sky. They and other physicists theorized that they were seeing the afterglow from the Big Bang's explosion. Since the Big Bang affected the entire universe at the same moment in time, the afterglow should permeate the entire universe and could be detected no matter what direction you looked. This afterglow is called the cosmic background radiation. Its wavelength and uniformity fit nicely with other astronomers' mathematical calculations about the Big Bang. OSCILLATING UNIVERSE An Albert Einstein’s favored model after rejecting his own original model. The oscillating universe followed the general theory of relativity equations of the universe with positive curvature. This curvature resulted in the expansion of the universe for a time, and then to its contraction due to the pull of its gravity in a perpetual cycle of Big Bang to Big Crunch. STEADY STATE THEORY Proposed by astronomers Fred Hoyle, Thomas Gold, and Hermann Bondi, this theory predicted a universe that expanded but did not change its density—matter was inserted into the universe as it expanded to maintain a constant density. INFLATIONARY UNIVERSE American physicist Alan Guth proposed a model of the universe based on the big bang theory. He incorporated a short early period of exponential cosmic inflation in order to solve the uncertainties of the standard big bang model, such as horizon and flatness problems. This became known as the inflationary model. Another variation of the inflationary model was the cyclic model developed by Paul Steinhardt and Neil Turok in 2002, which incorporated the ideas based on the superstring theory.  MULTIVERSE Russian-American physicist Andrei Linde developed the concept of inflationary universe from his chaotic inflation theory in 1983. This theory sees the universe as just one of many "bubbles" that grew as a part of a multiverse. American physicist Hugh. Everett III and Bryce DeWitt had initially developed and popularized the concept of "many worlds" structure of the universe in the 1960s and 1970s. Lesson 1.2 THE ORIGIN OF SOLAR SYSTEM THE SOLAR SYSTEM Solar system, assemblage consisting of the Sun—an average star in the Milky Way Galaxy—and those bodies orbiting around it: 8 (formerly 9) planets with about 170 known planetary satellites (moons); countless asteroids, some with their own satellites; comets and other icy bodies; and vast reaches of highly tenuous gas and dust known as the interplanetary m e d i u m. The Sun, Moon, and brightest planets were visible to the naked eyes of ancient astronomers, and their observations and calculations of the movements of these bodies gave rise to the science of astronomy. Today the amount of information on the motions, properties, and compositions of the planets and smaller bodies has grown to immense proportions, and the range of observational instruments has extended far beyond the solar system to other galaxies and the edge of the known universe. Yet the solar system and its immediate outer boundary still represent the limit of our physical reach, and they remain the core of our theoretical understanding of the cosmos as well. Earth-launched space probes and landers have gathered data on planets, moons, asteroids, and other bodies, and this data has been added to the measurements collected with telescopes and other instruments from below and above Earth’s atmosphere and to the information extracted from meteorites and from Moon rocks returned by astronauts. All this information is scrutinized in attempts to understand in detail the origin and evolution of the solar system—a goal toward which astronomers continue to make great strides. Composition of the Solar System Located at the center of the solar system and influencing the motion of all the other bodies through its gravitational force is the Sun, which in itself contains more than 99% of the mass of the system. The planets, in order of their distance outward from the Sun are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Four planets—Jupiter through Neptune—have ring systems, and all but Mercury and Venus have one or more moons. Pluto had been officially listed among the planets since it was discovered in 1930 orbiting beyond Neptune, but in 1992 an icy object was discovered still farther from the Sun than Pluto. Many other such discoveries followed, including an object named Eris that appears to be at least as large as Pluto. It became apparent that Pluto was simply one of the larger members of this new group of objects, collectively known as the Kuiper belt. Accordingly, in August 2006 the International Astronomical Union (IAU), the organization charged by the scientific community with classifying astronomical objects, voted to revoke Pluto’s planetary status and place it under a new classification called dwarf planet.  Origin Of The Solar System Supplementary Video: https://www.youtube.com/watch?v=SdxH9cnJbRQ Essential Question? If the universe formed from a single, infinitely small point that underwent inflation and expansion, how did the Solar System form? As the amount of data on the planets, moons, comets, and asteroids has grown, so too have the problems faced by astronomers in forming theories of the origin of the solar system. In the ancient world, theories of the origin of Earth and the objects seen in the sky were certainly much less constrained by fact. Indeed, a scientific approach to the origin of the solar system became possible only after the publication of Isaac Newton’s laws of motion and gravitation in 1687. Even after this breakthrough, many years elapsed while scientists struggled with applications of Newton’s laws to explain the apparent motions of planets, moons, comets, and asteroids. In 1734 Swedish philosopher Emanuel Swedenborg proposed a model for the solar system’s origin in which a shell of material around the Sun broke into small pieces that formed the planets. This idea of the solar system forming out of an original nebula was extended by the German philosopher Immanuel Kant in 1755. Early scientific theories Encounter Hypothesis - earliest theory for the formation of the planets was called the encounter hypothesis. In this scenario, a rogue star passes close to the Sun about 5 billion years ago. Material, in the form of hot gas, is tidally stripped from the Sun and the rogue star.  The Kant- Laplace Nebular Hypothesis Nebular Hypothesis states that the entire Solar System started as a large cloud of gas that contracted due to self-gravity. Kant’s central idea was that the solar system began as a cloud of dispersed particles. He assumed that the mutual gravitational attractions of the particles caused them to start moving and colliding, at which point chemical forces kept them bonded together. As some of these aggregates became larger than others, they grew till more rapidly, ultimately forming the planets. Because Kant was highly versed in neither physics nor mathematics, he did not recognize the intrinsic limitations of his approach. His model does not account for planets moving around the Sun in the same direction and in the same plane, as they are observed to do, nor does it explain the revolution of planetary satellites. A significant step forward was made by Pierre-Simon Laplace of France some 40 years later. A brilliant mathematician, Laplace was particularly successful in the field of celestial mechanics. Besides publishing a monumental treatise on the subject, Laplace wrote a popular book on astronomy, with an appendix in which he made some suggestions about the origin of the solar system.  Twentieth-century developments In the early decades of the 20th century, several scientists decided that the deficiencies of the nebular hypothesis made it no longer tenable. The Americans Thomas Chrowder Chamberlin and Forest Ray Moulton and later James Jeans and Harold Jeffreys of Great Britain developed variations on the idea that the planets were formed catastrophically—i.e., by a close encounter of the Sun with another star. The basis of this model was that material was drawn out from one or both stars when the two bodies passed at close range, and this material later coalesced to form planets. A discouraging aspect of the theory was the implication that the formation of solar systems in the Milky Way Galaxy must be extremely rare, because sufficiently close encounters between stars would occur very seldom. The next significant development took place in the mid-20th century as scientists acquired a more-mature understanding of the processes by which stars themselves must form and of the behavior of gases within and around stars. They realized that hot gaseous material stripped from a stellar atmosphere would simply dissipate in space; it would not condense to form planets. Hence, the basic idea that a solar system could form through stellar encounters was untenable. Furthermore, the growth in knowledge about the interstellar medium— the gas and dust distributed in the space separating the stars—indicated that large clouds of such matter exist and those stars form in these clouds. Planets must somehow be created in the process that forms the stars themselves. This awareness encouraged scientists to reconsider certain basic processes that resembled some of the earlier notions of Kant and Laplace.  Modern ideas The current approach to the origin of the solar system treats it as part of the general process of star formation. As observational information has steadily increased, the field of plausible models for this process has narrowed. This information ranges from observations of star-forming regions in giant interstellar clouds to subtle clues revealed in the existing chemical composition of the objects present in the solar system. Many scientists have contributed to the modern perspective, most notably the Canadian-born American astrophysicist Alistair G.W. Cameron. The favored paradigm for the origin of the solar system begins with the gravitational collapse of part of an interstellar cloud of gas and dust having an initial mass only 10–20 percent greater than the present mass of the Sun. This collapse could be initiated by random fluctuations of density within the cloud, one or more of which might result in the accumulation of enough material to start the process, or by an extrinsic disturbance such as the shock wave from a supernova. The collapsing cloud region quickly becomes roughly spherical in shape. Because it is revolving around the center of the Galaxy, the parts more distant from the center are moving more slowly than the nearer parts. Hence, as the cloud collapses, it starts to rotate, and, to conserve angular momentum, its speed of rotation increases as it continues to contract. With ongoing contraction, the cloud flattens, because it is easier for matter to follow the attraction of gravity perpendicular to the plane of rotation than along it, where the opposing centrifugal force is greatest. The result at this stage, as in Laplace’s model, is a disk of material formed around a central condensation. Protoplanet Hypothesis - The present working model on the formation of the Solar System is called the protoplanet hypothesis. This suggests that a great cloud of gas and dust of at least 10,000 million kilometers in diameter rotated slowly in space about 5,000 million years ago. As time passed, the cloud shrank under the pull of its own gravitation or was made to collapse by the explosion of a passing star. According to this hypothesis, the Solar System began with a fragment from an interstellar cloud composed mainly of hydrogen, helium, and trace amounts of the light elements. The fragments of the interstellar cloud then formed the dense central region of the solar nebula, which collapsed more rapidly than its outlying parts. As the solar nebula contracted, it rotated more rapidly, conserving its angular momentum. It also grew by accretion as materials continued to fall inward from its surroundings. The solar nebula eventually evolved into the sun. Gravitational instabilities ruptured the thin disk into eddies, each containing many small particles which built up and accreted. As the accretion continued, larger asteroid-sized aggregates called planetesimals were formed, which orbited the center of the solar nebula. The planetesimals further grew in size due to the gravitational attraction they exerted on to one another, forming moon-sized bodies that would later become planets. The planetesimals differed in chemical composition, depending primarily on their initial distance from the sun as they were formed. As a consequence, the terrestrial planets formed near the central portion of the solar nebula, where the temperatures were high enough to vaporize all compounds in the dust except the high-temperature metallic and silicate minerals in the inner portion of the disk. The gas giants, on the other hand, formed in the outer disk which remained relatively cooler, allowing them to be rich in volatile, icy, and gaseous materials. SUPPLEMENTARY VIDEOS: ▪ https://www.youtube.com/watch?v=SdxH9cnJbRQ ▪ https://www.youtube.com/watch?v=h38eie7mYIO ▪ https://www.youtube.com/watch?v=xxRflR9dGfY ▪ https://www.youtube.com/watch?v=fbq-NfLFLgk References https://www.nationalgeographic.com/science/space/universe/origins-of- the-universe/ https://www.rankred.com/origin-of-the-universe-different- theories/ https://en.wikipedia.org/wiki/Earth_science https://www.allaboutcreation.org/origin-of-the-universe.htm https://www.scholastic.com/teachers/articles/teaching-content/origin- universe/ https://www.britannica.com/science/solar-system https://great-home-decorations.com/earths-4-major-geological- subsystems/ https://www.britannica.com/science/solar- system/Planets-and-their-moons Exploring Life Through Science, 2nd edition, Olivar II et.al https://www.google.com/search?q=steady+state+theory+picture