Earth & Space

• ACTIVITIES ON THE SUN

  • solar wind - stream of high-energy particles sent into space; causes the light displays aurora borealis (if seen from Northern Hemisphere) and aurora australis (Souther Hemisphere)
  • prominences - storms that look like huge arches; may last several dages
  • solar flares - more intense than prominences; lasts only about 15 minutes
  • sunspots - cool black storm areas
• comets


  "dirty snowballs"; heads of ice and rock, tails of dust and gases forced from the head by solar radiation; tail always points away from the sun
• • meteoroid - chunk of rock or metal smaller than an asteroid
  • meteor - a meteoroid as it burns up in the atmosphere; "shooting star"
  • meteorite - a meteoroid that does not completely burn up
• KINDS OF TIDES

  1. Spring tides - strongest tides; when the sun, Earth, and moon are in a straight line; the sun's and the moon's gravities add up; highest and lowest tides
  2. Neap tides - weakest tides; when the sun, Earth, and moon form a right angle; the sun's and the moon's gravities cancel out one another; moderate tides
• Tidal bulges on Earth occur at opposite sides of the planet because the oceans are pulled toward the side facing the moon and away from the side turned away from the moon.
• Asteroids are small bodies orbiting the Sun between Mars and Jupiter. They are made mostly of rock and metal.
• COMMON STARS & CONSTELLATIONS

  1. Polaris - North Star; tip of Little Dipper's "handle"
  2. Sirius - brightest star in the night sky; "Dog Star"
  3. Ursa Major - Big Bear; contains the Big Dipper
  4. Ursa Minor - Little Bear; contains the Little Dipper
  5. Canis Major - Big Dog; contains Sirius
  6. Canis Minor - Little Dog
  7. Orion - The Hunter
  8. Proxima Centauri - closest star to Earth but is too small to be seen in the night sky
  9. Alpha Centauri - closest star to Earth that is visible in the night sky
  10. Pegasus - the Winged Horse
• Nebulae are clouds of gas and dust where new stars may form.
• OTHER TERMS

  • light year - the distance that light travels in one year
  • Milky Way - the galaxy where the solar system is
  • supernova - the explosion of a big star
  • black hole - remains of a supernova explosion with very strong gravity from which nothing can escape
• PLATE BOUNDARIES

  • Divergent - plates move away from one another, forming mid-ocean ridges
  • Convergent - plates move toward each other
  • oceanic-oceanic - one of the two oceanic plates is subducted into the mantle, magma rises, forming volcanoes, also creates trenches
  • oceanic-continental - oceanic plate is subducted into the mantle, magma rises, forming mountain ranges usually containing volcanoes
  • continental-continental - neither plate is fully subducted; the plates are forced into one another, forming tall mountains
  • Transform - plates slide past one another, causing earthquakes
• EARTHQUAKES

  • magnitude - "size" of an earthquake or energy released; measured by
  • Richter scale - 1 to 10 wherein magnitude 2 is ten times stronger than magnitude 1, and so on
  • Moment Magnitude scale - now more commonly used because of higher precision
  • intensity - amount of damage; measured using the Mercalli scale 1 to 12
  • focus - an earthquake's point of origin
  • epicenter - the point on the earth's surface directly above the focus
• TYPES OF ROCKS

  • igneous - from lava; e.g. granite, basalt
  • metamorphic - from other rocks that were changed due to intense heat and pressure; e.g. marble, slate
  • sedimentary - from sediments which were eroded to lower places; forms fossils; e.g. sandstone, shale
• clay -> silt -> sand -> pebbles -> gravel

  increasing particle size

  decreasing water-holding capacity
• Theory of Continental Drift - by Alfred Wegener (1912), the theory of the movement of the continents relative to each other; some evidences are:

  • fossils in Africa and South America
  • positions of mountain ranges
  • glacial striations - scratches in rock caused by movement of glaciers
  • tillites - glacial sediments buried in rock
• Theory of Plate Tectonics - theory that tectonic plates move; explains continental drift

  1. Pangaea - the "supercontinent" that existed during the Paleozoic and Mesozoic eras; broke up into Laurasia in the North and Gondwanaland in the South during the Mesozoic era
  2. Laurasia - started breaking up into Asia, Europe, and North America during the Cenozoic era
  3. Gondwanaland - started breaking up into Africa, Australia, Antarctica, and South America during the Mesozoic era
• ENERGY SOURCES

  • renewable energy sources - will not run out due to continuous use (e.g. solar, hydroelectric, geothermal)
  • non-renewable energy sources - in danger of running out (e.g. fossil fuels)
  • fossil fuels - energy sources that were formed by nature for hundreds of millions of years but which people are exploiting and may run out in just a few more years (e.g. petroleum, coal, natural gas)
• Global Warming

  the heating up of the earth's surface due to a build-up of greenhouse gases (e.g. carbon dioxide) in the atmosphere
• EFFECTS OF GLOBAL WARMING

  1. melting of polar ice caps - causing excessive flooding and even the loss of low-lying land
  2. climate change - e.g. increase in the number and intensity of typhoons and a shortening of the wet season
• WEATHER INSTRUMENTS

  1. barometer - air pressure
  2. anemometer - wind speed
  3. hygrometer - humidity
  4. wind vane - wind direction
  5. rain gauge - amount of rainfall
• KINDS OF STORMS

  • thunderstorms - clouds become electrically charged, producing lightning and thunder
  • tropical depression - up to 63 km/hr winds
  • tropical storm - 63-117 km/hr winds
  • typhoons - Pacific Ocean origin
  • hurricane - Atlantic Ocean origin
  • cyclone - Indian Ocean origin
  • tornadoes - small but about 500 km/hr
• LAYERS OF THE ATMOSPHERE

  1. Troposphere - life forms, weather, densest layer
  2. Stratosphere - ozone layer, airplanes
  3. Mesosphere - coldest, meteors burn up
  4. Thermosphere - ionosphere, hottest
  5. Exosphere - man-made satellites