MODULE 1 EARTH SCIENCE PDF

Earth Science Governor Pack Road, Baguio City, Philippines 2600 Tel. Nos.: (+6374) 442-3316, 442-8220; 444- Science, Technology, Engineering and 27...

Earth Science Governor Pack Road, Baguio City, Philippines 2600 Tel. Nos.: (+6374) 442-3316, 442-8220; 444- Science, Technology, Engineering and 2786; 442-2564; 442-8219; 442-8256; Fax No.: 442-6268 Email: [email protected]; Website: www.uc-bcf.edu.ph Mathematics MODULE I GRADE 11 Outline: 1. The Universe a. Structure, Composition, and Age of the Universe b. Origin of the Universe 2. The Solar System a. Origin of the Solar System b. Planets in the Solar System 3. Earth as the only Habitable Planet 4. Earth Systems and Subsystems a. Geosphere b. Hydrosphere c. Atmosphere d. Biosphere Learning Objectives: After completing the module, the students should be able to:  describe the structure and composition of the Universe;  state the different hypothesis that preceded the Big Bang Theory of the Origin of the Universe;  discuss the different hypotheses explaining the origin of the solar system.  define the concept of a system; and  recognize the Earth as a system composed of subsystems. UNIVERSE AND THE SOLAR SYSTEM Structure, Composition, and Age of the Universe Universe Definition: All existing matter and space considered as a whole; the cosmos. (Oxford Dictionary) The universe as we currently know comprises all space and time, and all matter and energy in it. It is made of 4.6% baryonic matter (“ordinary” matter consisting of protons, electrons, and neutrons: atoms, planets, stars, galaxies, nebulae, and other bodies), 24% cold dark matter(matter that has gravity but does not emit light), and 71.4% dark energy (a source of anti-gravity). Dark matter can explain what may be holding galaxies together for the reason that the low total mass is insufficient for gravity alone to do so while dark energy can explain the observed accelerating expansion of the universe. It comprises hydrogen, helium, and lithium as the three most abundant elements. Stars are the building block of galaxies which are born out of clouds of gas and dust in galaxies. Instabilities within the clouds eventually results into gravitational collapse, rotation, heating up, and transformation into a protostar which is the hot core of a future star as thermonuclear reactions set in. Stellar interiors are like furnaces where elements are synthesized or combined/fused together. Most stars such as the Sun belong to the so-called “main sequence stars.” In the cores of such stars, hydrogen atoms are fused through thermonuclear reactions to make helium atoms. Massive main sequence stars burn up their hydrogen faster than smaller stars. Stars like our Sun burn up hydrogen in about 10 billion years. The remaining dust and gas may end up as they are or as planets, asteroids, or other bodies in the accompanying planetary system. A galaxy is a cluster of billions of stars and clusters of galaxies form super clusters. In between the clusters is practically an empty space. Based on recent data, the universe is 13.8 billion years old. The diameter of the universe is possibly infinite but should be at least 91 billion light-years (1 light-year = 9.4607 × 1012 km) with a density of 4.5 x 10-31 g/cm3. SMALL SCALE STRUCTURE OF THE UNIVERSE: LARGE SCALE STRUCTURE OF THE UNIVERSE: FILAMENTS: Made up of clusters and or superclusters of galaxies. SUPERCLUSTERS are made up of clusters or different groups of galaxies. The Local Group It is called “Local Group” because our own galaxy - - the Milkyway galaxy is located here. Our Local Group belongs to the “Virgo Supercluster” VOID: Near Empty spaces in the universe. THE VIRGO SUPERCLUSTER AND THE SUPERCLUSTERS IN THE UNIVERSE SO HOW BIG IS THE UNIVERSE? HUBBLE VOLUME: THE OBSERVABLE “MAP” OF THE UNIVERSE - according to this - The universe is about 93 BILLION LIGHT YEARS WIDE. SOME EVIDENCE THAT THE UNIVERSE IS EXPANDING: Expanding Universe In 1929, Edwin Hubble announced his significant discovery of the “redshift” and its interpretation that galaxies are moving away from each other, hence as evidence for an expanding universe, just as predicted by Einstein’s Theory of General Relativity. He observed that spectral lines of starlight made to pass through a prism are shifted toward the red part of the electromagnetic spectrum, example toward the band of lower frequency; thus, the inference that the star or galaxy must be moving away from us. Red shift as evidence for an expanding universe show positions of the absorptions lines for helium for light coming from the Sun are shifted towards the red end as compared with those for a distant star. A. B. Figure 2. Red shift as evidence for an expanding universe. A. The positions of the absorptions lines for helium for light coming from the Sun B. are shifted towards the red end as compared with those for a distant star. (Source: http://www.cyberphysics.co.uk/Q&A/KS4/space/diagrams/ spectra.png)  1. REDSHIFT Hubble noted that light from faraway galaxies appeared to be stretched to longer wavelengths, or reddened. Wavelength Shorter=Blue=object towards us Longer= Red= objects away from us 2. COSMIC MICROWAVE BACKGROUND (CMB) -leftover radiation from the Big Bang or the time when the universe began. ORIGIN OF THE UNIVERSE A. Non-scientific Thoughts 1. Ancient Egyptians believed in many gods and myths which narrate that the world arose from an infinite sea at the first rising of the sun. 2. The Kuba people of Central Africa tell the story of a creator god Mbombo (or Bumba) who, alone in a dark and water-covered Earth, felt an intense stomach pain and then vomited the stars, sun, and moon. 3. In India, there is the narrative that gods sacrificed Purusha, the primal man whose head, feet, eyes, and mind became the sky, earth, sun, and moon respectively. 4. The monotheistic religions of Judaism, Christianity, and Islam claim that a supreme being created the universe, including man and other living organisms. B. Scientific Thoughts 1. Steady State Model The now discredited steady state model of the universe was proposed in 1948 by Bondi and Gould and by Hoyle. It maintains that new matter is created as the universe expands thereby maintaining its density. Its predictions led to tests and its eventual rejection with the discovery of the cosmic microwave background. CMB explains that the universe should be filled with radiation that is literally the remnant heat left over from the Big Bang. 2. Big Bang Theory As the currently accepted theory of the origin and evolution of the universe, the Big Bang Theory postulates that 13.8 billion years ago, the universe expanded from a tiny, dense and hot mass to its present size and much cooler state. The theory rests on two ideas, the General Relativity and the Cosmological Principle. Figure 3: Big Bang Timeline (Source: http://futurism.com/wp-content/uploads/2015/11/big-bang-theory-timeline1.jpg) Evolution of the Universe according to the Big Bang Theory From time zero (13.8 billion years ago) until 10−43 second later, all matter and energy in the universe existed as a hot, dense, tiny state. It then underwent extremely rapid, exponential inflation until 10−32 second later after which and until 10 seconds from time zero, conditions allowed the existence of only quarks, hadrons, and leptons. Then, Big Bang nucleosynthesis took place and produced protons, neutrons, atomic nuclei, and then hydrogen, helium, and lithium until 20 minutes after time zero when sufficient cooling did not allow further nucleosynthesis. From then on until 380,000 years, the cooling universe entered a matter-dominated period when photons decoupled from matter and light could travel freely as still observed today in the form of cosmic microwave background radiation.  As the universe continued to cool down, matter collected into clouds giving rise to only stars after 380,000 years and eventually galaxies would form after 100 million years from time zero during which, through nucleosynthesis in stars, carbon and elements heavier than carbon were produced. From 9.8 billion years until the present, the universe became dark-energy dominated and underwent accelerating expansion. At about 9.8 billion years after the big bang, the solar system was formed. ***Universe started as a singularity (hot infinitely dense point- few millimeters wide and is like a supercharged black hole). The singularity violently exploded. From this, all matter, energy, space and time were created. What happened next were two major stages. TWO MAJOR STAGES OF BIG BANG - 1. Radiation Era 2. Matter Era DIVIDED INTO EPOCH KEY EVENTS OR STAGES UNDER RADIATION ERA (DOMINANCE OF RADIATION) A. PLANCK EPOCH PLANCK Temperature: 10^40Kelvin -No matter and Energy Existed - Big Bang: Immediate Time after the -FORCES OF NATURE *SUPERFORCE -Gravity -Strong Nuclear -Weak -Electromagnetic ***at the end of this stage Gravity split off from the Superforce B. GRAND UNIFIED EPOCH GRAND UNIFIED Temperature: 10^36Kelvin -Named from the three remaining forces of nature. Time after the Big Bang: 10^-43 seconds GRAND UNIFIED THEORY -Strong nuclear -Weak -Electromagnetic **at the end of this stage, Strong Nuclear broke away C. INFLATIONARY EPOCH Temperature: 10^33Kelvin Time after the Big Bang: 10^-36 seconds INFLATIONARY -Universe rapidly expanded -Temperature- is very hot and churned electrons, quarks and antiquarks. D. ELECTROWEAK EPOCH Temperature: 10^20Kelvin Time after the Big Bang: 10^-32 seconds ELECTROWEAK -Electromagnetic and weak force finally split off  E. QUARK EPOCH Temperature: 10^16Kelvin Time after the Big Bang: 10^-12 seconds QUARK -All universe’s ingredients were present but universe is still too hot and dense for subatomic particles to form F. HADRON EPOCH Temperature: 10^10Kelvin Time after the Big Bang: 10^-6 seconds HADRON -Universe cooled down enough for quarks to bind and formed neutrons and protons G. LEPTON Temperature: 10^12Kelvin LEPTON AND NUCLEAR Time after the Big Bang: about 1 second --Proton and neutron fused and created a nuclei—in doing so, it created the first chemical element “Helium” H. NUCLEAR Temperature: 10^9Kelvin Time after the Big Bang: about 100 seconds --Ending the Radiation era—with the elements being created a new era came (Matter era) KEY EVENTS OR STAGES UNDER MATTER ERA (DOMINANCE OF RADIATION) (PRESENCE AND DOMINANCE OF MATTER) A. ATOMIC EPOCH Temperature: 3,000 Kelvin Time after the Big Bang: 50,000 years ATOMIC --Universe cooled down-enough for electrons to bind with the nuclei- this process is called “Recombination” (this process also gave rise to the 2nd element “Hydrogen” B. GALACTIC EPOCH Time after the Big Bang: 200 million years GALACTIC --Helium and Hydrogen dotted the universe with atomic clouds. -within the clouds, small pockets of gas may have had enough gravity to cause atoms to collapse. -clusters of atoms formed during galactic epoch became seedlings to form galaxies  C. STELLAR EPOCH Time after the Big Bang: 3 billion GALACTIC --Inside the galaxies stars begun to form -The formation of stars caused a tremendous ripple years effect -The heat within the converted Helium and Hydrogen to almost all of the other elements. -The elements became the building blocks in the creation of planets, moons, life and everything we see today. THE SOLAR SYSTEM The solar system comprises the Sun, eight planets, dwarf planets such as Pluto, satellites, asteroids, comets, other minor bodies such as those in the Kuiper belt and interplanetary dust. The Kuiper belt lies beyond Neptune while the Oort cloud marks the outer boundary of the solar system and is composed mostly of icy objects. The solar system is located in the Milky Way galaxy - a huge disc- and spiral-shaped aggregation of about at least 100 billion stars and other bodies. This galaxy is about 100 million light years across.The solar system revolves around the galactic center once in about 240 million years; The Milky Way is part of the so-called Local Group of galaxies, which in turn is part of the Virgo supercluster of galaxies; Any hypothesis regarding the origin of the solar system should conform to or explain both large scale and small scale properties of the solar system. Figure 4: The Solar System Source: https://www.universetoday.com/36487/difference-between-geocentric-and-heliocentric/ Large Scale Features of the Solar System 1. Much of the mass of the Solar System is concentrated at the center (Sun) while angular momentum is held by the outer planets. 2. Orbits of the planets are elliptical and are on the same plane. 3. All planets revolve around the sun. 4. The periods of revolution of the planets increase with increasing distance from the Sun; the innermost planet moves fastest, the outermost, the slowest; 5. All planets are located at regular intervals from the Sun. Small scale features 1. Most planets rotate prograde (counterclockwise) 2. Inner terrestrial planets are made of materials with high melting points such as silicates, iron, and nickel. They rotate slower, have thin or no atmosphere, higher densities, and lower contents of volatiles - hydrogen, helium, and noble gases. 3. The outer four planets - Jupiter, Saturn, Uranus and Neptune are called "gas giants" because of the dominance of gases and their larger size. They rotate faster, have thick atmosphere, lower densities, and fluid interiors rich in hydrogen, helium and ices (water, ammonia, methane). ORIGIN OF THE SOLAR SYSTEM Any acceptable scientific thought on the origin of the solar system has to be consistent with and supported by information about it (e.g. large and small scale features, composition). There will be a need to revise currently accepted ideas if the data no longer support them. Many theories have been proposed since about four centuries ago. Each has weaknesses in explaining all characteristics of the solar system. A few are discussed below: 1. Nebular Hypothesis In the 1700s Emanuel Swedenborg, Immanuel Kant, and Pierre-Simon Laplace independently thought of a rotating gaseous cloud that cools and contracts in the middle to form the sun and the rest into a disc that become the planets. This nebular theory failed to account for the distribution of angular momentum in the solar system.  2. Encounter Hypotheses Buffon’s (1749) Sun-comet encounter that sent matter to form planet; James Jeans’ (1917) sun- star encounter that would have drawn from the sun matter that would condense to planets, T.C. Chamberlain and F. R. Moulton’s (1904) planetesimal hypothesis involving a star much bigger than the Sun passing by the Sun and draws gaseous filaments from both out which planetisimals were formed. 3. Protoplanet Hypotheses - Current Hypothesis About 4.6 billion years ago, in the Orion arm of the Milky Way galaxy, a slowly-rotating gas and dust cloud dominated by hydrogen and helium starts to contract due to gravity (fig. 7). As most of the mass move to the center to eventually become a proto-Sun, the remaining materials form a disc that will eventually become the planets and momentum is transferred outwards. Due to collisions, fragments of dust and solid matter begin sticking to each other to form larger and larger bodies from meter to kilometer in size. These proto-planets are accretions of frozen water, ammonia, methane, silicon, aluminum, iron, and other metals in rock and mineral grains enveloped in hydrogen and helium. High- speed collisions with large objects destroys much of the mantle of Mercury, puts Venus in retrograde rotation. Collision of the Earth with large object produces the moon. This is supported by the composition of the moon very similar to the Earth's Mantle. When the proto-Sun is established as a star, its solar wind blasts hydrogen, helium, and volatiles from the inner planets to beyond Mars to form the gas giants leaving behind a system we know today. THE PLANETS IN THE SOLAR SYSTEM A planet is a celestial body that is in orbit around the Sun, has sufficient mass for its self- gravity to overcome rigid body forces so that it assumes a nearly round shape; and has cleared the neighborhood around its orbit. Dwarf planets are celestial body that has not cleared the neighborhood around its orbit and is not a satellite while small solar system bodies are all other objects except satellites orbiting around the sun such as asteroids, comets, and other small celestial bodies. Planets Overview of the Planets INNER PLANETS 1. Mercury o Mercury is the closest planet to the Sun, at a distance of 57.91 million kilometers / 35.98 miles away. o It has a mass of about 3.285×1023 𝑘𝑔 or about 5.5% that of Earth. o The smallest planet from the Solar System, o It is the second hottest and the second densest planet in the Solar System, with a density of 5.43 g/cm³ after Earth. A year in Mercury is just 88 days long. 2. Venus o Venus is referred to as the Earth’s sister planet due to their similar size and mass. o It is also the second largest planet from the Sun; the second largest terrestrial planet and the 2nd brightest object in the night sky after the Moon. o It is also called the morning and evening star. o It has a distance of distance of 108.2 million km/ 67.24 mi receiving the sun’s light in 6 minutes. 3. Earth o Earth is the third planet from the Sun, at a distance of 147 million km / 91 million mi. o It is situated in the goldilocks zone where temperatures are just right for liquid water to exist and for life to evolve. The diameter of Earth is around 12.742 km / 7.917 mi being the fifth largest planet from the solar system, and the largest of the terrestrial planets (Venus, Mercury, Mars). o o It takes Earth 265,25 days to complete one trip around the Sun – year. In order for calendars to maintain their consistency with this orbit, every 4 years one day is added – this is called a leap day – as well as a leap year. 4. Mars o The 4th planet from the Sun o 2nd smallest planet in the solar system o Often described as the “Red Planet” due to its reddish appearance o Mars The Earth227.9 is about makesmillion a complete km / rotation on its axis 141.6 million once from mi away every the 23.9Sun. hours. o One rotation/day on Mars is completed within 24.6 hours while a whole trip around the Sun or year, is completed within 669.6 days. OUTER PLANETS/JOVIAN PLANETS 5. Jupiter o 5th planet from the Sun and the largest planet in our solar system o It is two and a half times more massive than all other planets in the solar system combined. o Made primarily of gases and is therefore known as a “gas giant” o 4th brightest object in the solar system o It is the biggest planet of the Solar System, with a mean radius of 43.440 miles / 69.911 km. Almost 11 times bigger than Earth. 6. Saturn o Saturn – also nicknamed the “Ringed Planet”. o 6th planet from the Sun and the most distant that can be seen with the naked eye o Though the volume of Saturn is about 764 times that of Earth, it is the least dense planet in the solar system due to its gaseous composition. o Saturn has the second-shortest day in the solar system, completing a rotation quite quickly, in about 10.6 hours. 7. Uranus o Uranus is the sky god and the first ruler o 7th planet from the Sun; has the 3rd largest planetary radius and 4th largest planetary mass in the Solar System o Coldest planet in the Solar system that has 27 moons. o The density of Uranus 1.27 g/cm3 makes it the second least dense planet, after Saturn. o The interior rotation of Uranus is completed in about 17 hours, 14 minutes.  8. Neptune Neptune is the fourth largest and the farthest planet of the Solar System with the most powerful wind speeds out of all the planets. o Neptune has an average distance of 2.8 billion miles/4.5 billion kilometers away from the Sun. o Can complete a trip around the Sun in about 165 years with a day completed in 16.11 hours. o It spins on its axis very rapidly and has similar composition with Uranus. DWARF PLANETS o Ceres is the largest object in the asteroid belt, but was reclassified a dwarf 1. Ceres planet in 2006 – even though it’s 14 times smaller than Pluto. o Pluto is smaller than Earth’s moon, Pluto was a planet up until 2006 and has 2. Pluto five of its own moons. o Haumea lives in the Kuiper belt and is about the same size as Pluto. It spins 3. Haumea very fast, which distorts its shape, making it look like a football. 4. Makemake o Also in the Kuiper belt, Makemake is the second brightest object in the belt, behind Pluto. Makemake (and Eris) are the reason Pluto is no longer a planet. 5. Eris o Eris is the same size as Pluto, but three times further from the Sun. remote dwarf planet. THE EARTH AS THE ONLY HABITABLE PLANET Two requirements for a planet to become habitable: 1. Star should survive long enough for its planets to develop life. - this indicates that massive stars would have the least possibility to have habitable planets since they only live for relatively period. - Sun- medium mass star can survive long enough for life to develop. 2. The planet should exist in a region where water could remain liquid. - The planet must be located in the Goldilocks Zone- orbits of planets that are neither too hot nor too cold for life to exist - A planet with the right temperature enables water to remain in its liquid form which is necessary to maintain life. Temperatures: a) High- would change the phase of water from liquid to gas , b.) Low- would change its phase from liquid to soild. - Carbon - has unique properties that are the basis of life. Has four valence atoms which enables it to easily bond with other carbon atoms and create long complex molecules and polymers Ex: lipids, carbohydrates, proteins and nucleic acids Planet’s features not suitable for life o Mercury & Venus - too close to the Sun, they receive too much heat contributing to the increase in temperature of their surfaces. o Mars, Jupiter, Saturn, Uranus and Neptune - their distances from the sun are so far that the energy they receive is very little, making these planets very cold o Venus – very hot because it has a lot of active volcanoes that produce a very thick atmosphere. The thick atmosphere contributes to an increase greenhouse effect making the surface temperature very hot. o Mars - Has very little volcanic activity, as a result, it has thin atmosphere and cold surface temperature. o Jovian Planets –the outer four planets - Mainly composed of gases, there are no land where organisms can live. EARTH SYSTEMS AND SUBSYSTEMS The Earth is subdivided into different spheres. These spheres interact with one another, enabling Earth to sustain life. The interaction of the spheres is what makes Earth system, where one sphere cannot act independently from the rest. Earth system is essentially a closed system. It receives energy from the sun and returns some of this energy to space. A closed system is a system in which there is only an exchange of heat or energy and no exchange of matter. Figure 3: The Earth system. (Source: https://www.earthonlinemedia.com)  1. Atmosphere ( air sphere) The atmosphere is the thin gaseous layer that envelopes the lithosphere. The present atmosphere is composed of 78% nitrogen (N), 21% oxygen (𝑂2), 0.9% argon, and trace amount of other gases. One of the most important processes by which the heat on the Earth's surface is redistributed is through atmospheric circulation. There is also a constant exchange of heat and moisture between the atmosphere and the hydrosphere through the hydrologic cycle. Divisions of the Atmosphere a.Troposphere o Is the bottom 16 to 18 km of the atmosphere where wind, clouds and water vapor are found. o Layer with the most abundant gas in the atmosphere. It is where weather phenomena occur. b.Stratosphere o Lies above the troposphere. It is where the jet stream is found close to the troposphere. Jet stream is a column of horizontal wind blowing west to east and vise –versa; that aids in high speed travel o Bottom part is the ozone layer. c.Mesosphere o Lies above the stratosphere: cleanest layer where air grows colder against almost uniformly as one goes up because gases in this do not absorb the sun’s rays. o Meteors burn in this layer due to friction and are seen as shooting stars. o Layer of the atmosphere next to mesosphere d.Thermosphere o hottest layer reaching up to 10000 C o Regions where charged particles called ions formed o layer that makes possible radio communication e.Ionosphere o This is where auroras are formed. Auroras are beautiful, colorful displays of light only seen in the northern(aurora borealis) and southern hemispheres( aurora australis). f. Exosphere o Outermost layer that extends to the outer space. o Satellites, space probes, shuttles and other space crafts stay. o Exo or Celestial Sphere -(Outside or heavenly sphere ) includes the whole universe beyond the top of the atmopshere - the sun, moon, and stars as well as the asteroids and the little bits of dust that make meteors when they hit the atmosphere. 2. Lithosphere/ Geosphere The lithosphere includes the rocks of the crust and mantle, the metallic liquid outer core, and the solid metallic inner core. The Plate Tectonics are important processes shaping the surface of the Earth. The primary driving mechanism is the Earth's internal heat, such as that in mantle convection. Internal Structure of the Earth A.) Crust- uppermost layer of the solid earth: extends down to 32-38 km - Oceanic Crust( 8-10 km thick)- structure is uniform - a layer of sediment covers three layers of igneous rock - Continental Crust – (70 km thick) B. ) Mantle- silica- rich layer lies between crust and core (40 km-2, 897 km below the surface) Mohorovicic Discontinuity- boundary between crust and mantle; temperature is about 2,2000 degrees Celsius. C.) Core- inner portion of the earth a) Outer core- made up of molten rock about 2, 250 km thick b.) Inner core – solid about 1, 150km thick with an extreme high temperature of 2,2000 C  - 3. Biosphere - Biosphere is the set of all life forms on Earth. - It covers all ecosystems—from the soil to the rainforest, from mangroves to coral reefs, and from the plankton-rich ocean surface to the deep sea. - For the majority of life on Earth, the base of the food chain comprises photosynthetic organisms. During photosynthesis, 𝐶𝑂2 is sequestered from the atmosphere, while oxygen is released as a by-product. The biosphere is a 𝐶𝑂2 sink, and therefore, an important part of the carbon cycle. - ANTHROPHOSPHERE- “Human Sphere” - includes all parts of the Earth that has been modified by humans. 4. Hydrosphere (the water portion) -- About 70% of the Earth is covered with liquid water (hydrosphere) and much of it is in the - form of ocean water - Only 3% of Earth's water is fresh: two-thirds are in the form of ice, and the remaining one- - third is present in streams, lakes, and groundwater. The oceans are important sinks for 𝐶𝑂2 through direct exchange with the atmosphere and indirectly through the weathering of rocks. Heat is absorbed and redistributed on the surface of the Earth through ocean circulation. CRYOSPHERE- (“icy cold sphere”)- Frozen part of the Earth; glaciers, icebergs at sea, and the huge ice caps in Greenland and Antarctica.