[SCIENCE] 4QE - Sun-Moon-Earth

• The Sun

  • center of the solar system; medium-sized star
  • 150,000,000 km away from Earth
  • hydrogen (75%) & helium (24%)
• Outer Layers of the Sun

  • photosphere - glowing layer on sun’s surface (visible & orange)
  • chromosphere - layer above photosphere
  • corona - outer layer of the sun; seen during solar eclipses
• Inner Layers of the Sun

  • core - innermost layer; greatest amount of energy
  • radiative zone - passageway for all energy released at core
  • convection zone - outermost layer of sun
• • sunspots - dark areas found in photosphere; cooler than rest of sun
  • solar flares - stream off the sun (explosions)
  • prominences - loop-like
• The Earth

  • only planet to maintain life; 4.5 billion years old
  • third planet in the Solar System
  • ”one astronomical unit”
• Inner Core - Layers of the Earth

  • solid, hot, dense ball of iron

  Outer Core - Layers of the Earth

  • liquid iron and nickel
• Layers of the Earth

  • mantle - makes up most of interior; layer of molten rock between solid crust and hot, dense core
  • gutenbag - core and mantle
  • mohorovicic - mantle and crust
  • crust - outermost layer; makes up 1% of Earth’s mass; made up of solid rocks and minerals
  • continental crust - older, thicker
  • oceanic crust - younger, denser
• The Moon

  • sole natural satellite
  • Giant Impact Theory (Theia)
• Moon’s Orbit & Rotation

  • rotating at same rate around Earth - synchronous rotation
  • one complete orbit in 27 days
  • from our perspective, Moon appears every 29 days
• Surface of the Moon

  • solid, rocky surface from asteroids, meteorites & comets
  • thin and negligible atmosphere (exosphere)
  • lunar regolith - charcoal-gray, powdery dust, rocky debris
  • highlands - light areas of the moon
  • maria or mare - darks features of the moon
• Layers of the Moon

  • crust - outermost layer w/ dusty & rocky outer layer (regolith)
  • mantle - divided into two;
  • rigid lithosphere - upper mantle
  • athenosphere - lower mantle (hot enough to flow)
  • core - innermost layer; solid, iron-rich part surrounded by liquid iron core in turn is surrounded by partially molten layer
• Earth’s Rotation

  • rotation of the Earth divides it into lit-up half and dark half, which causes day and night
  • Earth takes 24 hours to complete one rotation - counterclockwise
  • Earth’s axis of rotation is 23.5 (causing different seasons)
• Earth’s Revolution

  • movement of the Earth around the Sun in a fixed path (west to east)
  • Earth takes one complete revolution in 365 1/4 days
  • called an orbit, Earth’s orbit is elliptical
  • solstice - a day with longest or shortest
  • equinox - a day with equal duration of day and night
• Eclipses & Tides

  • eclipse - occurs relative to the positions of Earth, Sun & Moon; Solar Eclipse & Lunar Eclipse
• Solar Eclipse

  • occurs when moon is positioned between Earth & Sun
  • total solar eclipse - when moon exactly covers Sun
  • partial solar eclipse - only a portion of Sun is blocked by moon
  • annular solar eclipse - disk is seen to be surrounded by a thin ring
• Lunar Eclipse

  • occurs when moon moves within Earth’s shadow
  • total lunar eclipse - the moon is entirely on umbra of Earth’s shadow
  • partial lunar eclipse - only a part of moon passes through umbra
  • penumbral lunar eclipse - moon passes only through penumbra
• Tides

  • regular fluctuations in ocean sea levels where water level is high or low
  • caused by combined gravitational force of sun and moon
  • however, since moon is closer to earth, it is the main cause of tides