General Science Pointers PDF

GENERAL SCIENCE POINTERS Oceanography: The exploration and study of the ocean. Science and Technology Paleontology: The science of the forms of Science...

GENERAL SCIENCE POINTERS Oceanography: The exploration and study of the ocean. Science and Technology Paleontology: The science of the forms of Science life that existed in prehistoric or geologic - is a systematic study that is concerned periods. with facts and principles, and methods that could be observed in our natural or physical Meteorology: The science that deals with and social environment. It comes from the the atmosphere and its phenomena, such as Latin word 'scire' that means 'to know’. weather and climate. - is both a body of knowledge and a process 3. Scientific Method – away of thinking, a way of solving problems is the logical method used by scientists to acquire knowledge that is used to explain The Branches of Science different phenomena in nature. A thing observed by the senses is called a 1. THE PHYSICAL SCIENCES phenomenon; a scientifically tested observation is called a fact. Physics: The study of matter and energy and the interactions between them. The scientific method has six basic Physicists study such subjects as gravity, steps, namely: light, and time. Albert Einstein, a famous physicist, developed the Theory of a. Identify and clearly state the Relativity. problem. Questions arise from something observed as unusual; problem that is Chemistry: The science that deals with the specific, measurable, and attainable is composition, properties, reactions, and the identified. structure of matter. The chemist Louis Pasteur, for example, discovered b. Gather information pertinent to the pasteurization, which is the process of problem. This is done by recalling past heating liquids such as milk and orange experiences concerning the problem, juice to kill harmful germs. interviewing people who are knowledgeable of the problem, and researching Astronomy: The study of the universe in libraries and research centers. beyond the Earth's atmosphere. c. Formulate hypothesis. Based on 2. THE EARTH SCIENCES information or data gathered, an 'educated guess' can be made. Geology: The science of the origin, history, and structure of the Earth, and the physical, chemical, and biological changes that it has experienced or is experiencing. d. Test the hypothesis. Carrying out 4. Energy experiments. The term energy is derived from the Greek Controlled experiment - manipulating one word, energeia (en meaning in and ergon , of the conditions or factors that may affect meaning work). Anything that is able to do the result of experiment. work possess energy. Energy is the ability to 1) Trials - number of times experiment is do work or the ability to exert force on an repeated. object and make it move. 2) Controls - factors that are kept constant FORMS OF ENERGY throughout the experiment a. Mechanical Energy 3) Variables - factors that change during the experiment. kinetic energy – energy possessed by an object or a body in motion Kinds: 1. Independent or experimental - factors that are changed. potential energy- energy possessed by a body because of its 2. Dependent - factors that change as a position or state result of changes in the independent b. Internal Energy or Thermal Energy e. Draw a generalization or – total energy coming from the attractive conclusion. and repulsive forces of all the particles or molecules in a body Conclusion - a statement about the result of the experiment. c. Heat Energy – energy which flows from one body to another due to a temperature Law - a statement which describes what difference between them, and the flow is happens but does not explain the cause of always from the hotter to the colder body the occurrence. d. Electrical Energy – electricity is the Theory - hypothesis that can be explained energy of electrons flowing through from observations. conductors, like copper wires and aluminum wires. f. Apply the principle (conclusion) to other situations. e. Chemical Energy – energy stored in matter due to forces of attraction and to the arrangement of subatomic particles in atoms and of atoms in the molecules of substances. f. Radiant Energy – energy of the 6. ENERGY RESOURCES electromagnetic waves , radio waves, infrared rays, visible light, ultraviolet rays, x a. Fossil Fuels rays and gamma rays. 1. Coal – being mined formed from trees g. Nuclear Energy – energy released from and other vegetation buried in swamps nuclear fusion or fission of atomic nuclei of crated by the heavy element or light element. encroaching sea 5. METHODS OF HEAT 2. Petroleum - a liquid mixture of gaseous TRANSFER liquid and solid hydrocarbons. Conduction 3. Natural Gas- composed entirely of carbon The molecules in a material are always and hydrogen. It is 50 to 94% methane and moving. When one part of a material is other hydrocarbons. heated, the molecules in that part move faster and collide with other molecules. As b. Hydroelectric Power this goes on, heat is conducted from Hydroelectric power pertains to the molecule to molecule until the heat is production of electricity by means of spread throughout the material. This is generators driven by water conduction. A conductor is the material turbines. through which heat passes easily. An insulator is a material that conducts heat c. Geothermal Energy - Thermal energy poorly. inside the earth, energy of steam from beneath the earth’s surface Convection d. Wind Energy- energy harnessed The movement of a gas or liquid brought through the windmill about by temperature differences creates a convection current. Heat is transferred by e. Solar Energy- energy from the sun, Convection when a gas or liquid moves from radiant energy. The visible light is one place to another. harnessed to produce the electricity by means of so-called solar cells or Radiation photovoltaic cells, which generate electricity when exposed to sunlight Heat transfer when heat is given of in all directions around them is radiation. The sun and other hot objects radiates energy.  7. Earth BIG BANG FORMATION OF SOLAR SYSTEM -In the beginning there is only a As matter began to condense and stars super-massive gaseous point in our empty began to form, one such star appeared universe. Instantaneously and randomly, where the Sun now appears within the enough energy is created to break the Milky Way Galaxy. After igniting with fusion gravitational bond holding this massive and burning its usable hydrogen and other body together, exploding the super-heated larger elements, the star exploded, sending particles throughout space. In less than one matter out in all directions. Once again, millionth of a second, protons, neutrons, through gravitational forces, this matter electrons, and their anti-particles begin to eventually cooled and collected in a few key form. areas, forming the planets and the asteroid belt. The asteroid belt is simply an early As time moves on, particles begin to cool by form of the collection of matter that was not giving off energy, which allows them to able to completely form a planet due to combine to create the first and most simple Jupiter's gravity. Some early planets may ion, hydrogen, as well as a few more massive have collided with other early planets, atoms. More time passes; the atoms are creating larger planets, moons, or possibly becoming more abundant in the universe. space rocks. In the meantime, a smaller star They begin to pull together through atomic began to form at the center of the previous forces and the gravitational force. Gaseous explosion and our Sun started its fusion bodies become more massive, attracting process again. more atoms and becoming more massive. The gravitational force of these early bodies is so great that they collapse in on themselves, beginning fusion. Hydrogen atoms combine, yielding larger atoms and enormous amounts of energy; enough energy to keep these stars from collapsing. Eventually, the fusion process has to end and the star will explode, sending out more massive atoms into the universe. Over time, these atoms collect and combine to create planets, smaller stars, asteroids, and numerous other solid bodies.  8. Earth’s Structure (2,900 km) thick and makes up nearly 80 percent of the Earth's total volume. The three main layers are the core,mantle and the crust. THE CRUST - The crust lies above the mantle and is the earth's hard outer shell, The earth is surrounded by the atmosphere. the surface on which we are living. In Till this moment it hasn't been possible to relation with the other layers the crust is take a look inside the earth because much thinner. It floats upon the softer, the current technology doesn't allow it. denser mantle. The crust is made up of solid Therefore all kinds of research had to be material but these material is not done to find which material the earth everywhere the same. There is an Oceanic consists, what different layers there are and crust and a Continental crust. The first one which influence those have (had) on the is about 4-7 miles (6-11 km) thick and earth's surface. This research is called consists of heavy rocks, like basalt. The seismology. Continental crust is thicker than the Oceanic crust, about 19 miles (30 km) thick. THE CORE - The inner part It is mainly made up of light material, like of the earth is the core. This part granite. of the earth is about 1,800 miles (2,900 km) below the earth's surface. The core is a Plate Tectonics dense ball of the elements iron and nickel. It is divided into two layers: the inner The earth's crust consists of a number of core and the outer core. moving pieces or plates that are always colliding or pulling apart. The Lithosphere The inner core - the center of consists of nine large plates and twelve earth - is solid and about 780 smaller ones. The continents are embedded miles (1,250 km) thick. in continental plates; the oceanic plates make up much of the sea floor. The study of The outer core is so hot that the metal Tectonic plates - called plate is always molten, but the inner core tectonics - helps to explain continental drift, pressures are so great that it cannot melt, the spreading of the sea floor, volcanic even though temperatures there reach eruptions and how 6700oF (3700oC). The outer core is about mountains are formed. 1370 miles (2,200 km) thick.Because the earth rotates, the outer core spins around the inner core and that causes the earth's Magnetism. THE MANTLE - The layer above the core is the mantle. It begins about 6 miles (10 km) below the oceanic crust and about 19 miles (30 km) below the continental crust (see The Crust). The mantle is to divide into the inner mantle and the outer mantle. It is about 1,800 miles Continental drift the Asthenosphere the subducted plate melts. At the surface an ocean trench is The drift of the plates across the surface of created, followed by an arc of islands. In this the earth has been going on over millions of area also volcanic activities and earthquakes years, which still changes the outward occur. appearance of the earth. When you look at the map of the world, you see how well the east coast of North and South America fits Seafloor Spreading into the west coast of Europe and Africa. Over millions of years these continents have Studies show that volcanic activity under slowly drifted apart. (continental drift). the sea causes magma from beneath the earth’s crust to rise to the surface, forming a Diverging plates very long ridge along the middle of the oceans that separate the large continents. Where plates pull apart, hot molten rock When continental plates collide, one of the (fluid magma) emerges as lava and so new plates splits up into two layers: a lower layer matter is added to the plates. In this way of dense mantle rock and an upper layer of new oceanic plates are formed. The place lighter crystal rock. As the mantle layer where this happens is known as a mid-ocean subducts, the upper layer is peeled off and ridge. Mid-ocean ridges are rarely more crumples up against the other plate, thus than about 4,920 ft. (1,500 m) high, but forming mountain ranges, like the Alps. they may snake along the ocean bed for These are called crumpled mountains. thousands of miles. Beneath each of the world's great oceans there is a mid-ocean DIASTROPHISM – the process which ridge. An example is the Mid-Atlantic Ridge involves movements of the earth’s crust in the Atlantic Ocean, which stretches from such that a portion is pushed up, push down the North Pole to the South Pole. Mid-ocean or forced sideways ridges are areas of much volcanic and earthquake activity. Folding – the process when the sideward forces acting on rocks deform the rocks into Converging plates: wavelike folds after tilting, bending of In many places the huge plates of the earth's wrinkling. surface are slowly moving together with unimaginable force.Sometimes the edge of Faulting sliding or moving over of rock one plate is gradually destroyed by the force layers over one another along the break or of collision, sometimes the impact simply fracture, may occur vertically or crimps the plates' edges, thereby creating horizontally. great mountain ranges.When one tectonic plate bends beneath the other, it is called subduction. Most of the time this happens because a dense oceanic plate collides with a lighter continental plate. You can see this along the Pacific coast of South- America. The oceanic plate dips beneath into the Asthenosphere. Through the heat of  9. Volcanoes Composite volcano: These are also built up from alternate layers of lava and A Volcano is a gap in the earth where ash but, besides its main crater, it has many molten rock and other materials come to the little craters on its slope. earth's surface.Some volcanoes are just cracks in the earth's crusts. Others are weak Caldera volcano: An older volcano with a places in the earth's crust, which occur on large crater which can be 62 miles(100km) places where magma bubbles up through wide. In this crater many little new craters the crust and comes to the earth's surface. are formed. Magma is molten rock that occurs by partial melting of the crust and the mantle by high 10. Earthquakes temperatures deep down in the ground. Once magma comes to the earth's surface it An Earthquake is in fact the shaking of the is called lava. ground caused by sudden movements in the earth's crust. The biggest earthquakes are ACTIVE AND NON-ACTIVE set off by the movement of tectonic plates. VOLCANOES Some plates slide past each other gently, but others can cause a heavy pressure on the There are volcanoes in different phases of rocks, so they finally crack and slide past activity: each other. By this,vibrations or shock waves are caused, which go through the Active volcanoes- are likely to erupt at ground. It is these vibrations or seismic any moment waves which cause an earthquake. The closer to the source of the earthquake (the Dormant volcanoes-lie dormant for focus or hypocenter), the more damage centuries, but then erupt suddenly and occurs. Earthquakes are classified according violently to the depth of the focus. Extinct volcanoes-ones no longer likely to The closer the focus to the surface, the erupt. heavier the earthquake. The earthquake is always the most intense on the surface TYPES OF VOLCANOES: directly above the focus (Epicenter). In general big earthquakes begin with light Shield volcano: This is a broad, shallow vibrations (foreshocks). These are the initial volcanic cone, which arises because the fractures in the rocks. After the main shock, running lava, which is fluid and hot, cools there may be minor aftershocks, most of the slowly. time for months. This occurs as the rocks settle down. Dome volcano: This one has a steep, convex slope from thick, fast- cooling lava. Ash-cinder volcano: Throws out - besides lava - much ash into the air. Through this the volcanic cone is built up from alternate layers of ash and cinder.  11.)Rocks rocks begin to melt. Partially molten metamorphic rocks are known as Rocks are classified in three types based on migmatite. As melting proceeds with how they are formed. increasing temperatures and depths of burial, eventually the rock becomes molten a. Igneous rocks are formed when molten and becomes magma, which cools and rock (magma) from within Earth cools and crystallizes to form plutonic igneous rock, or solidifies. There are two types: intrusive which is erupted onto the Earth's surface as igneous rocks solidify beneath Earth's lava, and cools and crystallizes to form surface; extrusive igneous rocks solidify volcanic igneous rock. Further at the surface. Examples: Granite, basalt, complications within the rock cycle include obsidian (1) weathering of sedimentary and metamorphic rocks (in addition to igneous b. Sedimentary rocks are formed when rocks), and (2) metamorphism of igneous sediment (bits of rock plus material such as rocks and repeated metamorphism of shells and sand) gets packed together. They metamorphic rocks. can take millions of years to form. Most rocks that you see on the ground are WEATHERING – Breaking down of rocks sedimentary. Examples: Limestone, brought about by either physical or chemical sandstone, shale means giving rise to sediments or theIr rock fragments. c. Metamorphic rocks are sedimentary or igneous rocks that have been transformed Types of Weathering by heat, pressure or both. Metamorphic rocks are usually formed deep within Earth, A. Physical or mechanical weathering during a process such as mountain building. Examples: Schist, marble, slate Frost wedging - water expands when it freezes THE ROCK CYCLE The three major types of rocks, igneous, Exfoliation or unloading -rock breaks off sedimentary, and metamorphic rocks are into leaves or sheets along joints which interrelated by a series of natural processes. parallel the ground surface caused by Igneous rocks form from the cooling and expansion of rock due to uplift and erosion; crystallization of hot molten lava and removal of pressure of deep burial; magma. Igneous rocks undergo weathering and erosion to form sediments. Sediments Thermal expansion - are deposited and lithified by compaction and cementation to form sedimentary rocks. -repeated daily heating and cooling of rock; Sedimentary rock become buried by -heat causes expansion; cooling causes additional sedimentary deposition, and contraction. when they are deep within the Earth, they are subjected to heat and pressure which -different minerals expand and contract at causes them to become metamorphic rocks. different rates causing stresses along With further burial and heating, the mineral boundaries. metamorphic B. Chemical weathering 2. Oxidation Rock reacts with water, gases and solutions (may be acidic); will add or remove -Oxygen combines with iron-bearing silicate elements from minerals. minerals causing "rusting" 1. Dissolution (or solution) - Iron oxides are produced. Iron oxides are -Several common minerals dissolve red, orange, or brown in color in water halite - Mafic rocks such as basalt (which may calcite contain olivine, pyroxene, or amphibole) weather by oxidation to an orange color Limestone and marble contain calcite - "Georgia Red Clay" derives its color from and are soluble in acidic water the oxidation of iron bearing minerals Marble tombstones and carvings are 3. Hydrolysis particularly susceptible to chemical weathering by dissolution. Note that the urn C. Biological weathering and tops of ledges are heavily weathered, Organisms can assist in breaking down rock but the inscriptions are somewhat sheltered into sediment or soil. and remain legible. 1. Roots of trees and other plants Caves and caverns typically form in 2. Lichens, fungi, and other microorganisms limestone speleothems are cave formations 3. Animals (including humans) speleothems are made of calcite form a rock called travertine EROSION- the process by which rock stalactites - hang from ceiling fragments and sediments are carried along stalagmites - on the ground by such agents as wind and running water Karst topography forms on limestone terrain and is characterized by: DEPOSITION- the process by which rock caves/caverns, fragments and sediments ae carried by sinkholes, agents of erosion are disappearing streams dropped or deposited in other places. springs COMPACTING – the process by which rock fragments and other materials that accumulated, usually at the bottom of a thick column of water, get cemented together and harden into rock METAMORPHISM - a change in constitution of a rock brought about by pressure, heat and chemical action resulting in a more compact and highly crystalline condition of the rock. 12. Minerals and Gems The Troposphere is the layer where the weather happens. Above this layer is the Minerals are solid, inorganic (not living) Stratosphere and in between them is the substances that are found in and on earth. Ozone layer, that absorbs the sun's harmful Most are chemical compounds, which ultraviolet rays. Above the Stratosphere is means they are made up of two or more the Mesosphere, the Thermosphere elements. For example, the mineral including the Ionosphere - and the sapphire is made up of aluminum and Exosphere. The atmosphere measures about oxygen. A few minerals, such as gold, silver 500 miles (800km). and copper, are made from a single element. Minerals are considered the building blocks Layers of the Atmosphere of rocks. Rocks can be a combination of as many as six minerals.Many minerals, such THE TROPOSPHERE as gold and silver, are very valuable because they are beautiful and rare.Limestone, clay The Troposphere is the lowest layer of the and quartz are other examples of minerals. atmosphere and measures about 7 miles(12 km). It contains over 75 percent of all the Gems are minerals or pearls that have been atmosphere's gases and vast quantities of cut and polished. They are used as water and dust. As the sun heats the ground, ornaments, such as jewelry. it keeps this thick mixture churning. The weather is caused by these churnings of the Precious stones are the most valuable mass. The troposphere is normally warmest gems. They include diamonds, rubies and at ground level and cools higher up where it emeralds. reaches its upper boundary (the tropopause). The tropopause varies in 13. Atmosphere height. At the equator it is at 11.2 miles(8 km) high, at 50 N and 50 S, 5.6 miles(9 km) What is Atmosphere? and at the poles 3.7 miles(6 km) high. The earth is surrounded by all kind of gases. STRATOSPHERE This layer is called the earth's Atmosphere. Without this atmosphere life on earth isn't The Stratosphere extends from the possible. It gives us air, water, heat, and tropopause up to its boundary (the protects us against harmful rays of the Stratopause), 31 miles(50 km) above the sun and against meteorites. Earth's surface. In this layer there is 19 percent of the atmosphere's gases and it This layer around the earth is a colorless, contains little water vapour. Compared to odorless, tasteless 'sea' of gases, water and the troposphere it is calm in this layer. The fine dust. The atmosphere is made up of movements of the gases are slow. Within the different layers with different qualities. It stratosphere is the ozone layer, a band of consists of 78 percent nitrogen, 21 percent ozone gas, that absorbs harmful ultraviolet oxygen, 0.93 percent argon, 0.03 percent rays of the sun. The higher you get in the carbon dioxide and 0.04 percent of other atmosphere, the warmer the air gets. gases. MESOSPHERE EXOSPHERE The mesosphere is the next layer above the The Exosphere is the outermost layer of the stratopause and extends to its upper atmosphere and extends from 430 miles boundary (the Mesopause), at 50 miles(80 (700 km) to 500 km) above the ground. The gases in the miles (800 km) above the ground. In this mesosphere are too thin to absorb much of layer gases get thinner and thinner and drift the sun's heat. Although the air is still thick off into space. enough to slow down meteorites hurtling into the atmosphere. They burn up, leaving fiery trails in the night sky. The 14. Air temperatures in the mesosphere drop to -184 oF(-120 oC) at the mesopause. AIR MOVEMENT THERMOSPHERE Warm air is less dense than cold air. Thus, warm air rises above cold air making the The Thermosphere is the layer above the pressure below lower. The horizontal mesopause. The gases of the thermosphere movement of air from high pressure area to are even thinner lower pressure area produces wind. than those in the mesosphere, but they absorb ultraviolet light from the sun. SEA BREEZES AND LAND BREEZES Because of this, the temperatures rise to 3,600 oF (2,000 oC) at the top. This When spending a day at the beach, a is at a height of 430 miles (700 km) of the noticeable drop in temperature may occur earth's surface. In the during the early afternoon as a cool breeze thermosphere is a separate layer, the begins to blow off of the water. This wind is Ionosphere. This layer extends of 62 known as the "sea breeze", which occurs in miles(100 km) to 190 miles(300 km) response to differences in temperature of the earth's surface. between a body of water and neighboring land. IONOSPHERE Sea-breeze circulations most often occur on The ionosphere is part of the thermosphere. warm sunny days during the spring and It is made of electrically charged gas summer when the temperature of the land is particles (ionised). The particles get this normally higher than the temperature of the electric charge by ultraviolet rays of the sun. water. During the early morning hours, The ionosphere has the important quality of the land and the water start out at roughly bouncing radio signals, transmitted from the same temperature. On a calm morning, the earth. That’s why places all over the a given pressure surface will be at the same world can be reached via radio. height above both the land and water. A few hours later, the sun's energy begins to warm the land more rapidly than the water. By later in the day, the temperatures of the a. Cirrus clouds are thin and wispy land increases while the temperature of the clouds that are blown by high winds. water remains relatively constant. This They usually mean the day will have occurs because water, especially large fair or pleasant weather, and follow bodies of water like a lake or ocean, are able the direction that the air moves at to absorb more energy than land without the altitude they are found at. warming. b. Cirrostratus clouds are like very It is important to remember that the air is thin sheets of clouds that cover large not heated directly from above by the sun. parts of the sky. In fact, most of the incoming solar energy actually passes right through the c. Cirrocumulus clouds look like atmosphere. However, as the land absorbs small round puffs in the sky. this energy, heat is radiated back into the Sometimes they are called mackerel atmosphere (from the earth), warming the clouds because they look similar to overlying air. Some of this heat is fish scales. transported to higher levels in the atmosphere through convection. d. Altostratus clouds are made up of ice crystals and water droplets. They On the other hand, since the temperature of can cover the entire sky and form the water remains relatively constant before rain storms. throughout the day, the air over the water is not heated from below (as over land), e. Altocumulus clouds are resulting in lower air temperatures over the composed of water droplets and are water. On clear, calm evenings, temperature gray and puffy. These clouds are differences between a body of water and usually seen on warm and humid neighboring land produce a cool wind that summer mornings and are usually a blows offshore. This wind is called a "land sign that thunderstorms will follow breeze". Land breezes are strongest along later in the day. the immediate coastline but weaken considerably further inland. f. Nimbostratus clouds are dark gray clouds that produce falling rain 15. Weather and Climate or snow. WEATHER- describes the condition of the g. Stratus clouds are among the atmosphere in a particular time (cool and low-lying clouds. They are gray dry, humid, windy, rainy, or stormy) clouds that cover the entire sky and can be the result of very thick fog CLIMATE- average weather in a region lifting in the morning. over a number of years or usually decades (tropical) h. Stratocumulus clouds are low, lumpy, and gray. They are the most CLOUDS - little drops of water or ice common clouds. Often they do not hanging in the atmosphere. A ceilometer produce precipitation. When they do measures the height of clouds. it’s light rain or snow.  The lightning is seen before the thunder is WIND SYSTEMS heard because light travels faster than sound. a. Northeast Trade Winds – from north, north east and east Thunderstorms need three things: b. Southwest Monsoon (habagat) – Moisture—to form clouds and rain. originates from Southeast Trade winds south of the equator Unstable Air—relatively warm air that can rise rapidly. c. Northeast monsoon (amihan)- from east, south east Lift—fronts, sea breezes and mountains are capable of lifting air to help form CYCLONES – low pressure areas in the thunderstorms. tropics Lightning a. tropical depression- with wind speed of less than 63 kph The action of rising and descending air within a thunderstorm separates positive b. tropical storm – with wind speed of and negative charges. Water and ice 63-118 kph particles also affect the distribution of electrical charge. Lightning results from the c. typhoon – with wind speed of more than buildup and discharge of electrical energy 118 lph between positively and negatively charged areas. Most lightning occurs within the Thunderstorms cloud or between the cloud and ground. Thunderstorms affect small areas when Astronomy compared with hurricanes and winter storms. The typical thunderstorm is 15 miles The Universe in diameter and lasts an average of 30 minutes. Nearly 1,800 thunderstorms are How old is the universe? What is it made of? happening at any moment around the 13.7 billion years: Age of the universe world. That's 16 million a year! 200 million years: Interval between the Despite their small size, all thunderstorms Big Bang and the appearance of the first are dangerous. Every thunderstorm stars produces lightning, which kills more people 4%: Proportion of the universe that is each year than tornadoes. Strong winds, ordinary matter hail, and tornadoes are also dangers 23%: Proportion that is dark matter associated with some thunderstorms. 73%: Proportion that is dark energy You can estimate how many miles away a storm is by counting the number of seconds between the flash of lightning and the clap of thunder. Divide the number of seconds by five to get the distance in miles. COLORS OF THE UNIVERSE The Milky Way is our own galaxy. Just about all that you can see in the Blue Planets - Earth, Neptune, and sky belongs to our galaxy—a system Uranus are all blue because of gases of roughly 200 billion stars. The in their atmosphere. Milky Way is a spiral-shaped galaxy about 100,000 light-years in Blue Stars - These are the hottest diameter and about 10,000 stars, with a surface temperature of light-years in thickness. more than 37,000°F. The solar system is made up of the Yellow Stars - These are warm stars, Sun (solar means sun) at its center, such as the Sun. Their temperature the nine planets that orbit it, and the is about 10,000°F. various satellites, asteroids, comets, and meteorites that are also Red Stars- The coolest stars are red. controlled by the Sun's gravitational Their surface temperature is less pull. than 5,500°F. Red Shift - When light coming from The Sun is the closest star to Earth a distant star is seen through a and the center of our solar system. spectroscope (an instrument that Every second, it converts 49 million separates light into its different tons(45 million metric tons) of colors); the light we receive matter into pure energy, which continues to shift toward the red reaches us in the form of light. The area of the spectrum, whichis the Sun weighs morethan 300,000 least powerful. This means that, times as much as Earth and is 109 since the light is becoming weaker times larger. and weaker, the stars must be traveling away from us. This makes Sunspots appear as dark spots on the scientists believe that our universe is Sun, and are believed to be cooler expanding. than the rest of the Sun. They appear in 11-year cycles. Red Spot - A swirling cloud on the planet Jupiter is a raging storm of Planet is the term used for a body in gases, mainly red phosphorus. orbit around the Sun. The word comes from the Greek planetes, and Galaxies are immense systems means“wanderers.” Our solar system containing billions of stars. has nine planets: Mercury, Venus, Astronomers have estimated that the Earth, Mars, Jupiter, Saturn, universe could contain 40 to 50 Uranus,Neptune, and Pluto. billion galaxies. Galaxies have different shapes: some are spiral, others are elliptical, or oval-shaped, and some are irregular.  Satellite (or moon) is the term for a Our Sun is the nearest star. Stars are body in orbit around a planet. As very large — some are even bigger long as our own Moon was the only than planets. Our Sun has a moon known, there was no need for diameter of 865,400 miles—making a general term for the moons of it a comparatively small star. planets. But when Galileo Galilei discovered the four main moons of White dwarfs occur when a star runs the planet Jupiter, Johannes Kepler out of energy and shuts down. The wrote Galileo a letter suggesting he force of gravity at its center pulls the call them “satellites” (from the Latin mass of the star in on itself, forcing it satelles, which means attendant). to collapse. It resembles the glowing The word means the same thing as cinders of a fire that has died “moon.” down.It is called a white dwarf because it emits a white glow. Orbit is the term for the path traveled by a body in space. It comes Brown Dwarfs are also called failed from the Latin orbis, which means stars. They lack enough energy to be circle.Some orbits are nearly true stars but are also too massive circular, but the orbits of most and hot to be planets. planets are ellipses—shaped like ovals. A supernova is an extremely large exploding star. Just before the star Asteroids, also known as the minor dies, it releases huge amounts of planets, are small bodies orbiting the energy,briefly becoming millions of Sun that resemble planets. More times brighter than it was. Then it than 5,000 asteroids have been immediately shrinks. discovered, and most are found between Mars and Jupiter. Neutron stars are formed after a supernova explodes and shrinks. The Comets are made up of frozen dust shrunken form of the star becomes and gases, and have been described incredibly dense and compact as as large, dirty snowballs with icy gravity pulls all of its matter inward. centers. They often travel on It becomes so compressed that a extremely elongated orbits around million tons of its matter would the Sun. hardly fill a thimble. This density crushes together the electrons and Meteors are fragments of comets, protons that makeup its atoms, planets, moons, or asteroids that turning them into neutrons. have broken off.Those that do not disintegrate completely but fall to Pulsars are believed to be rapidly Earth are called meteorites. spinning neutron stars that give off bursts of radio waves at regular Stars are composed of intensely hot intervals.Pulsar is a shortened gasses, deriving their energy from version of pulsating star. nuclear reactions going on in their  Quasars (quasistellar objects) are believed to be the most remote Mercury objects in the universe. Despite their small Mercury, the planet closest to the Sun, has almost no atmosphere, and its dusty surface A black hole is created by the total of craters resembles the Moon. The planet gravitational collapse of a massive was named for the Roman god Mercury, a star or group of stars. It is the final winged messenger, and it travels around the phase of some stars, in which gravity Sun faster than any other planet. Mercury is sucks the star in on itself—it difficult to see from Earth—in fact, the implodes rather than explodes. This famous astronomer Nicolaus Copernicus, makes it so dense that not even light for all his years of research and observation, can escape its gravitational field. never once was able to see Mercury. A nebula is a giant glowing cloud Venus thought to be made up of dust and gas. Venus is often called Earth's twin because the two planets are close in size, but that's Corona - The very hot outermost the only similarity. The thick clouds that layer of a star's atmosphere. Our cover Venus create a greenhouse effect that Sun's corona can only be seen during keeps it sizzling at 864°F. Venus, a total solar eclipse. named after the Roman goddess of love and beauty, is also known as the “morning star” Solar Flares - A magnetic storm on and “evening star” since it is visible at these the Sun's surface which shows up as times to the unaided eye. Venus appears as a a sudden increase in brightness. bright, white disk from Earth. Solar Prominences - Gases trapped Earth at the edge of the Sun which appear to shoot outward from the Sun's Earth is not perfectly round; it bulges at the surface. equator and is flatter at the poles. From Solar wind - A continuous stream of space the planet looks charged particles which are released blue with white swirls, created by water and from the Sun and hurled outward clouds. into. Sunspot - A magnetic storm on the Sun's surface which appears as a dark area. THE PLANETS There are nine planets in our solar system including Earth. So far, no life as we know it exists on any planet other than our own.  Mars Uranus Because of its blood-red color (which comes Uranus is a greenish-blue planet, twice as from iron-rich dust), this planet was named far from the Sun as its neighbor Saturn. for Mars, the Roman god of war. Mars is the Uranus wasn't discovered until 1781. Its fourth planet from the Sun, situated discoverer, William Herschel, named it between Earth and Jupiter. Three-quarters Georgium Sidus (the Georgian star) after red, Mars also has dark blotches on it and the English king, George III. Later its name white areas at the poles—these are white was changed to Uranus, after an ancient polar ice caps. Greek sky god, since all the other planets had been named after Roman and Greek Jupiter gods. It has 27 moons and 11 rings. A belt of asteroids (fragments of rock and Neptune iron) between Mars and Jupiter separate the four inner planets from the five outer Neptune, named for an ancient Roman sea planets. Jupiter, the largest planet in our god, is a stormy blue planet about 30 times solar system, was named for the most farther from the Sun than Earth. Neptune important Roman god because was discovered when astronomers realized of its size. About 1,300 Earths would fit into that something was exerting a gravitational it. Viewed through a large telescope, Jupiter pull on Uranus, and that it was possible that is stunningly colorful—it is a disk covered an unknown planet might be responsible. with bands of blue, brown, pink, red, Through mathematical calculations, orange, and yellow. Its most distinguishing astronomers determined there was indeed feature is “the Great Red Spot,” an intense an undiscovered planet out in space—a year windstorm larger in size than Earth, which before it was actually seen for the first time has continued for centuries without any through a telescope (in 1846). It has 13 signs of dying down. It has 63 moons and 4 satellites and 4 rings. rings. Pluto Saturn Pluto, named after the Roman and Greek Saturn, the second-largest planet, has god of the underworld, is the coldest, majestic rings surrounding it. Named for smallest, and outermost planet in our solar the Roman god of farming, Saturn was the system. Pluto and its moon, Charon, are farthest planet known by the ancients. called “double planets” because Charon is so Saturn's seven rings are flat and lie inside large it seems less of a moon than another one another. They are made of billions of ice planet. Pluto was predicted to exist in 1905 particles. It has 31 moons and about 1000 and discovered in 1930. It is the only planet rings. that has not yet been studied closely by a space probe. During each revolution around the sun, Pluto passes inside Neptune's orbit for 20 years, making Neptune the outermost planet for that time.  THE MOONS The moons of Jupiter: Jupiter has 63 Earth's Moon is a small ball of gray rock moons. 45 of these moons were discovered revolving 239,000 miles around Earth. It is between 2000 and 2003. Astronomers just one of many in the solar system. The believe that the moon count of Jupiter could Moon has no air and no water. It is about go as high as 100. The newer moons were one-fourth as large as Earth.The Moon named after members of the god Jupiter's travels around Earth in an oval orbit at (Zeus to the Greeks) entourage, among 36,800 kilometers per hour. The Moon does them : Themisto, Iocaste, Harpalyke, not have an atmosphere, so temperatures Praxidike, Taygete, Chaldene, Kalyke, range from -184 degrees Celsius during its Callirrhoe, Megaclite, Isonoe, and Erinome. night to 214 degrees Celsius during its day except at the poles where the temperature is The moons of Saturn: Saturn has 31 a constant -96 degrees Celsius. The Moon is moons. 12 of them were discovered in late actually a little lopsided due to the lunar 2000 and another one was announced in crust being thicker on one side than the 2003. other. When you look at the Moon, you will see dark and light areas. The dark areas are The moons of Uranus: Uranus has 27 young plains called maria and are composed moons. Astronomers detected five of them of basalt. The basalt flowed in and flooded between 1787 and 1948. The space probe the area created by a huge impact with an Voyager discovered 10 more in 1985 and asteroid or comet. The light areas are the 1986. highlands, which are mountains that were uplifted as a result of impacts. The The moons of Neptune: Neptune has 13 lunar surface is covered by a fine-grained moons, with Triton the largest. It is covered soil called “regolith” which results from the with a frosty crust, where active volcanoes constant bombardment of the lunar rocks by shoot crystals of nitrogen that look like small meteorites. geysers. The surface temperature of Triton is –390°F, making it the coldest object in “Full Moon and No Moon the solar system. Five new Neptunian describe two phases of the Moon as it orbits moons were discovered in 2002. Earth. When the Moon is between the Sun and the Earth, its sunlit side is turned away from the Earth and we say there is no Moon. When the Earth is between the Sun and Moon, we can see the entire sunlit side of the Moon and call it a full Moon. The Far Side of the Moon is always facing away from Earth because of the force of gravity. So when we look at the Moon, we always see the same side.