Planet Earth Science Presentation PDF

Our planet is a remarkable place, full of diverse and interconnected systems that work together to sustain life as we know it. From the air we breathe to the water we drink, the Earth's atmosphere, hydrosphere, geosphere, and biosphere all play important roles in creating the environment that we ca...

Our planet is a remarkable place, full of diverse and interconnected systems that work together to sustain life as we know it. From the air we breathe to the water we drink, the Earth's atmosphere, hydrosphere, geosphere, and biosphere all play important roles in creating the environment that we call home.  EONS ERAS PERIODS EPOCH “CHAOTIC EON” - 4.54 - 4.0 GA THE SURFACE OF THE EARTH WAS BOMBARDED BY METEORITES SEVERE VOLCANISM FREQUENT PLANETISIMAL COLLISIONS THE CORES AND CRUST STABILIZED FORMATION OF MOON Diameter: Approx. 3,476 kilometers Mass: Approx. 81 quintillion pounds Distance (Earth): Approx. 384,400 kms. Orbital Period: Approximately 27.3 Earth days Gravity: Approximately one-sixth of Earth'sgravity - 4.0 - 2.5 GA FOSSIL EVIDENCE OF EARLIEST LIFE FORM; PROKARYOTIC MICROBES ATMOSPHERE CONTAINED MOSTLY METHANE RECORDED PRIMITIVE OCEAN AND ATMOSPHERE (ARCHEAN OCEAN) NO EVIDENCE OF GLACIATION “EON OF GREAT CHANGES” - 2.5 GA - 541 MA ORIGIN OF EUKARYOTIC LIFE APPEARANCE OF OXIGEN- DEPENDENT ORGANISMS (EDIACARA FAUNA) OXYGENATION OF ATMOSPHERE FORMATION AND BREAK UP OF SUPERCONTINENTS GLACIATION PALEOZOIC ERA (541 MA - 252 MA) BEGINS WITH CAMBRIAN EXPLOSION - MARINE SHELLED INVERTIBRATES SILURIAN: LEAFLESS VASCULAR PLANTS AND INVERTEBRATE ANIMALS WERE ESTABLISHED ON LAND DEVONIAN: VERTEBRATE ANIMALS TRANSIT TO LAND VIA EVOLUTION OF AMPHIBIANS FROM AIR BREATHING FISH PALEOZOIC ERA (541 MA - 252 MA) MISSISSIPPIAN: LARGE AMOUNT AMPHIBIANS, SHARK ABUNDANCE PENNSYLVANIAN: LARGE NONFLOWERING PLANTS CARBONIFEROUS: FLIGHT WAS FIRST ACHIEVED PERMIAN (end of Palezonic Era): - 95% marine invertebrate extinction - rise of reptiles MESOZOIC ERA (252 MA - 66 MA) TIME OF DINOSAURS TIME OF GEOLOGICAL AND BIOLOGICAL TRANSITION TRIASSIC: THERAPSIDS AND THECODONTS DOMINATION APPEARANCE OF THE FIRST MAMMAL (MEGAZOSTRODON) JURASSIC AND CRETACEOUS: DINOSAURS DOMINATION MESOZOIC ERA ENDED WITH MASS EXTINCTION CENOZOIC ERA (66 MA - PRESENT) FORMATION OF MOUNTAIN RANGES AND CANYONS (HIMALAYANS) GLACIERS COVERED THE NORTHERN HEMISPHERE TREMENDOUS DIVERSIFICATION OF LIFE (MAMMOTH, MARSUPIAL KANGAROO) PLEISTOCENE: RECORDED EARLY HUMAN LIFE MAJOR EXTINCTION OF MAMMALS 10,000 - 8,000 YEARS AGO The Ever-Evolving Planet  However, since earth is also rotating, the centrifugal force (a force pulling away The current shape of the from the center) planet earth is not a distorts the sphere, perfect sphere, but an which in effect causes oblate spheroid. Earth the area near the obtained this shape specifically because of its equator to be bulging gravity and rotation. Same outward compared to with the other planets, the other portions of gravity pulls the mass the sphere, and closer to its core, which in almost flattened at its the Earth’s case, the core is the center of its gravity. poles.