Earth Science

SCIENCE: EARTH SCIENCE Solar System Sun the luminous • Photosphere: surface layer of the sun or a star; what Earthlings see. Chromosphere: a stratum of the • upper atmosphere in which photochemical reactions are prevalent. • Corona: a colored circle around the sun; outermost part of the atmosphere. • Solar flares: a sudden temporary outburst of energy from a small area of the sun's surface. • Sunspots: dark spots on the surface; relatively colder than any part. • Prominence: a mass of gas resembling a cloud that arises from the chromosphere. wind: plasma • Solar continuously ejected from the sun's surface into and through interplanetary space. • Aurora borealis: occurs in earth’s northern hemisphere. • Aurora australis: occurs in earth’s southern hemisphere. The Terrestrial Planets • Mercury • Venus, The Morning Star • Rotates opposite to other planets (Sun rises in the west and sets in the East) • Day longer than year • Earth • Mars The Jovian Planets/The Gas Giants • Jupiter • Moons: Io, Callisto, Ganymede, Europa • Has the Big Red Spot (a storm) • Saturn - The Ringed Planet The Ice Giants • Uranus - axial tilt of 98º (spins on its side) • Neptune - blue because of methane The Kuiper belt • Pluto - no longer a planet Asteroid belt • Ceres Heavenly bodies Stars • Polaris - the northern star (where Earth’s axis points to); part of the Little Dipper’s handle • Sirius - the brightest night star; Dog Star • Alpha Centauri star system - the closest to the Solar system; triple star system • Alpha Centauri (A and B) - a binary pair • Proxima Centauri - the closest star to the sun; invisible red dwarf Constellations • Ursa Major - from the Latin word ursae meaning bear; contains the Big Dipper • Ursa Minor - contains the Little Dipper • Canis Major - from the Latin word canis meaning dog; contains Sirius • Canis Minor - the puppy • Orion - The Hunter The Zodiac Signs Aries - The Ram Taurus - The Bull Gemini - The Twins Cancer - The Crab Leo - The Lion Virgo - The Virgin Libra - The Scales Scorpio - The Scorpion Sagittarius - The Archer Capricorn - The Sea Goat Aquarius - The Water Bearer Pisces - The Fishes The Earth • Axial tilt: 23.5 degrees • Axial precession: 25,772 years (~26,000 years) • Days per revolution (Earth year): 365.2422 days (~ 365.25 days) • Seasons due to the axial tilt • Eclipses • Solar eclipse - sun-moonearth; moon covers the sun. • Lunar eclipse - sun-earthmoon; moon appears red. • Tides • Neap tide - weak; sun, earth, & moon form a 90degree angle. • Spring tide - strong; sun, earth, & moon are in a straight line. • Solstices & Equinoxes, caused by revolution. • Summer solstice - June 21 • longest daylight (northern hemisphere) • overhead sun at Tropic of Cancer (23.5º N) • Fall equinox - September 23 • Winter solstice - December 22 nighttime • longest (northern hemisphere) • overhead sun at Tropic of Capricorn (23.5º S) • Spring/Vernal equinox March 21 Planetary motions • Rotation - movement on an axis • Revolution - movement around a star • Precession - wobbling of the axis. The moon • “Luna” • No atmosphere • Revolution (with respect to the stars): 27.32 days In synchronous rotation • with the Earth, therefore it only shows one side (rotation period ≅ revolution period) • Soviet Lunar Program - first unmanned mission in 1959 • Apollo 11 - first manned landing in 1969 (Neil Armstrong) Phases of the moon Types of shadows • Umbra (Latin umbra meaning shadow) cone of • central darkness which tapers away from the Earth or Moon • • • total solar eclipse observed. Penumbra (Latin paena meaning almost) • outer cone of partial shadow which diverges instead oftapering • partial solar eclipse observed Antumbra • annular solar eclipse is observed (thin disk of light around the moon) Composition of the Earth • 71% water geology, a • In discontinuity is a surface at which seismic waves change velocity • The Earth’s Layers, from innermost to outermost • Inner core • Outer core • Gutenberg discontinuity • Mantle • Lower mantle • Upper mantle • Mohorovičić discontinuity • Crust • Rocks • Igneous • solidification of magma • oldest rocks • Examples: basalt, granite, rhyolite, obsidian, pumice • Sedimentary through • formed lithification • often found near water resources contains • sometimes fossils • Examples: conglomerate, breccia, sandstone, shale • Metamorphic through • formed recrystallization • often has foliation (parallel lines) • Examples: quartzite, marble, slate, phyllite, schist, gneiss The Earth’s Atmosphere Composition and layers • 77% Nitrogen, 22% Oxygen, 1% others • Troposphere - densest; where weather forms • Stratosphere - where airplanes fly; ozone layer • Mesosphere - where meteors burn; coldest • Thermosphere - contains the ionosphere; hottest • Exosphere - boundless; where artificial satellites are found Meteorology • study of earth’s atmosphere, weather, & climate • Weather - daily condition • Climate general condition of temperature andprecipitation (intertropical • ITCZ convergence zone) - where trade winds meet; usually where cyclones form boundary • Front separating masses of air with different densities (usually because of temperature) Clouds • Cirrus: ice crystals; means fair weather; highest • Cumulus: fluffy • Stratus: low-lying • Nimbo- (prefix): rain • Alto- (prefix): middle-altitude Monsoons in the Philippines • Amihan: Northeast monsoon • February to March • Habagat: Southwest monsoon • June to September/October Breezes • Air moves from high pressure to low pressure • Sea breeze (day) - HP: sea, LP: land • Land breeze (night) - HP: land, LP: sea Plate Tectonics Plate boundaries • Divergent • Oceanic-oceanic - mid-ocean ridges • Seafloor Spreading Theory (Harry Hess): • • • newest rocks are near the ridge Continental-continental valleys – Convergent • Oceanic-oceanic trenches, volcanic islands/island arcs (e.g. Hawaii) Oceanic-continental • mountain (range) & trench • Continental-continental mountain (range) Transform • forms a strike-slip fault (e.g. San Andreas fault) Continental drift theory • by Alfred Wegener striations • Glacial scratches on rocks because of moving glaciers • Tillites - glacial sediments in rocks • Pangaea/Pangea supercontinent that existed before continental drift • Laurasia included Asia, Europe, and North America • Gondwanaland included South America, Antarctica, Africa, Australia, and India Earthquakes • Magnitude scale - amplitude of ground motion; measured using a seismograph • Richter scale • 0.0 to 10.0 • a 1.0 increase means a 10 times stronger earthquake • Intensity scale - based on observations (i.e. damages); usesthe Mercalli scale • Terminology • fault - plate fracture • normal fault - footwall rises relative to hanging wall • reverse/thrust fault hanging wall rises relative to footwall • • focus/hypocenter origin of an earthquake along theplate epicenter - point on Earth’s surface directly above the focus Seismic Waves Body waves • P wave (primary) • Fastest to move • Can pass through solids and liquids Longitudinal wave (i.e. • wave propagation is in the same direction as particle movement) • S wave (secondary) • Second fastest to move • Can only pass through solids • Transverse wave (wave propagation perpendicular to particle movement) Surface waves • L/Q wave (Love) • Third fastest to move • Transverse waves • What most people feel during an earthquake, slow decay leads to most destructive effects • R wave (Rayleigh) • Slowest to move • Includes both longitudinal and transverse motions (sort of moves in a circular motion) Terms in Astronomy Light year - the distance light travels in an earth year Supernova - the explosion of a big star; star death Black hole - remnants of a supernova with a very strong gravitational force Meteors • Meteoroid - in space • Meteor - in Earth’s atmosphere • Meteorite - reached the Earth’s surface Perihelion • from the Greek peri, meaning around; and helios meaningsun • the point in the orbit of a planet, asteroid, or comet at which it is closest to the sun (for the Earth, it is at January 4) Aphelion • the point in the orbit of a planet, asteroid, or comet at which it is furthest from the sun (for the Earth, it is at July 4) Other Information Sputnik - first artificial satellite in space (by the Soviets) Valentina Tereshkova - first woman in space Yuri Gagarin - first human in space Laika - first dog in orbit Curiosity & Opportunity - rovers in Mars • the latter was temporarily shut down due to dust storms Diwata-1 - first satellite built and designed by Filipinos Diwata-2 - second Filipino microsat, launched on October 29, 2018 The Geological timescale Eon Phanerozoic Era Cenozoic (age of mammals) Period Quaternary Tertiary Subperiod Neogene Paleogene Epoch Holocene Pleistocene age) Pliocene (ice Miocene forests grasslands) Oligocene elephants trunks, horses, grasses) (kelp and Eocene Mesozoic (age of reptiles) Paleozoic (age of insects, fishes, invertebrates) Precambrian Proterozoic (bacteria, archaeans, eukaryotes) Archaean (toxic atmosphere) Paleocene Cretaceous Jurassic (land dinosaurs) *Breakup of Pangaea Triassic (ferns, conifers, etc) Permian (mass extinction) Carboniferous (insects, amniote egg) Devonian (fishes, vascular plants) Silurian (glacial melting, coral reefs, fish with jaws) Ordovician (Gondwanaland) Cambrian (explosion sudden increase in biodiversity) Pennsylvanian Mississippian Pridoli Ludlow Wenlock Llandovery Lopingian Guadalupian Cisuralian (first with early &