Science

• Earth is locked in an elliptical path around the sun which is known as the orbit
• Earth travels around the sun along an orbit and completes one revolution in approximately 365 days and six hours which is equivalent to one year
• The moon revolves around the earth in about 27.322 days
• Eclipse


  Examples of formation of shadows in space
• Sun


  Luminous and the source of light in space
• Earth and moon


  Non-luminous and opaque
• Types of eclipse

  • Solar eclipse
  • Lunar eclipse
• Solar eclipse


  1. Moon comes between the sun and the earth

  2. Shadows of the moon falls on the earth
• Umbra


  Part of the moon's shadow that fully covers the sun
• Antumbra


  Area of the shadow beyond the point of umbra where the moon is fully in front of the sun but doesn't cover the total part
• Penumbra

  Area of the shadow where only a small portion of the moon is in front of the sun
• Lunar eclipse

  1. Earth situated between moon and the sun

  2. Earth blocks out the sun's rays shining on the moon

  3. Moon appears reddish in colour
• Partial lunar eclipse


  When it looks like someone has taken a bite out of the moon
• Total lunar eclipse


  When the full moon is visible
• During solar eclipse


  Order is sun, moon, earth
• During lunar eclipse


  Order is sun, earth, moon
• Lunar eclipses are quite frequent and can be seen at any part of the world at night time
• Solar eclipses are less frequent than lunar eclipses
• Joanna, Grade 7 Super Science Teacher: 'Always remember that learning becomes easy once you explore'
• Seasons


  Different periods of the year that are distinguished by special weather and climate conditions
• Seasons


  • Spring
  • Summer
  • Autumn
  • Winter
• Seasons


  • Different amount of light received from the sun
  • Different temperatures
  • Different weather conditions that repeat
• Axis


  An imaginary line passing through the center of the earth that goes through both the north pole and the south pole
• Rotation


  The spinning motion of earth around its axis
• Revolution


  The movement of the earth around the sun
• It takes 24 hours or one day for the earth to completely rotate around on its axis
• It takes 365 and 1/4 days or one year for the earth to move around the sun
• Earth's axis


  • Tilted at an angle of 23.5 degrees
• Earth's axis is tilted


  Different parts of the earth receive different amounts of sunlight as the earth revolves around the sun
• Different amounts of sunlight


  Results in different temperatures and different weather conditions we call seasons
• Solstice


  When the axis of the earth points forward or away from the sun
• Summer solstice occurs on June 21 or 22, winter solstice occurs on December 21 or 22
• North pole tilted toward the sun in June


  Northern hemisphere tilted toward the sun, receives more direct rays, experiences longer daytime and warmer temperatures
• North pole tilted away from the sun in December

  Northern hemisphere receives less direct rays, experiences shorter daytime and cooler temperatures
• Equinox


  When the axis of the earth does not point either toward or away from the sun, resulting in equal day and night
• Vernal equinox is on March 21 or 22, autumnal equinox is on September 21 or 22
• Philippines climate


  Only experiences wet and dry seasons, not four seasons, due to location near the equator
• Rainy season in Philippines is from June to November, dry season is from December to May</b>
• Seasons occur due to tilt of earth's axis, revolution of earth around sun, and direct rays of sun
• The earth is constantly moving around the sun and the moon is constantly moving around the earth