1 / 31

Cycles of the Sun

Cycles of the Sun. Length of Days & Nights Seasons. Length of Days & Nights. The Earth rotates on its axis A complete rotation takes a little over 24 hours (1 day) One side of the Earth is always facing the Sun. Length of Days & Nights. The side of the Earth facing the Sun has day

kim
Download Presentation

Cycles of the Sun

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Cycles of the Sun Length of Days & Nights Seasons

  2. Length of Days & Nights • The Earth rotates on its axis • A complete rotation takes a little over 24 hours (1 day) • One side of the Earth is always facing the Sun

  3. Length of Days & Nights • The side of the Earth facing the Sun has day • The side of the earth facing away from the Sun has night

  4. As the Earth Rotates… • The side of the Earth in the sunlight spins away and becomes night • The side of the Earth in the dark spins toward the Sun and becomes day

  5. Changing Length of Day & Day • The number of hours of daylight received each day depends on the latitude. • The equator receives about 12 hours of daylight all year long

  6. Changing Length of Day & Day • The hemisphere that is tilted toward the Sun gets more hours of daylight that the hemisphere tilted away from the Sun • Latitudes closest to the equator have less change in hours of daylight • Latitudes further from the equator have more dramatic changes in hours of daylight

  7. Seasons • The Earth is tilted on its axis

  8. Seasons • The tilt does not change – it always remains pointed in the same direction

  9. Seasons • As the Earth revolves around the Sun, the tilt sometimes points toward the Sun, sometimes away from the Sun, and sometimes neither away nor toward the Sun

  10. Seasons • The hemisphere that is tilted toward the Sun has summer • Longer days (more hours of sunlight) • Warmer weather

  11. Seasons • The hemisphere that is tilted away from the Sun has winter • Shorter days (less hours of sunlight) • Cooler weather

  12. Seasons • When the Earth is positioned so that the tilt is neither towards nor away from the Sun, we have Spring and Fall • Moderate temperatures • Days and nights of similar length

  13. Seasons: Summer(Northern Hemisphere) • Position of the Earth is such that the northern hemisphere is tilted toward the Sun • Summer Solstice (1st day of summer) • Sun at highest point (over Tropic of Cancer) • Most hours of sunlight (longest day) • About June 21

  14. Seasons: Fall(Northern Hemisphere) • Position of the Earth is such that the northern hemisphere is tilted neither towards nor away from the Sun • Autumnal Equinox (1st day of fall) • About 12 hours of sunlight • About September 22

  15. Seasons: Winter(Northern Hemisphere) • Position of the Earth is such that the northern hemisphere is tilted away from the Sun • Winter Solstice (1st day of winter) • Sun at lowest point (over Tropic of Capricorn) • Fewest hours of sunlight (shortest day) • About December 21

  16. Seasons: Spring(Northern Hemisphere) • Position of the Earth is such that the northern hemisphere is tilted neither towards nor away from the Sun • Vernal Equinox (1st day of spring) • About 12 hours of sunlight • About March 21

  17. Energy from the Sun(Insolation)

  18. Summing Up: Winter - Earth tilted away from Sun, fewer hours of sunlight, less direct sunlight (insolation) Spring – Earth neither tilted away nor toward the Sun, equal hours of daylight and night Summer – Earth tilted toward the Sun, more hours of daylight, more direct sunlight (insolation) Fall - Spring – Earth neither tilted away nor toward the Sun, equal hours of daylight and night

  19. Watch this animation:http://www.shsu.edu/%7Echm_tgc/sounds/flashfiles/earth.swf

  20. Works Cited • http://www.wrh.noaa.gov/hnx/newslet/spring03/dryjanuaries.htm • http://www.nasa.gov/worldbook/wbkids/k_dayandnight.html • http://www.lpi.usra.edu/education/skytellers/day_night/activities/cycle_of_light.shtml • http://www.nps.gov/lacl/graphics/sun_earth2.jpg • http://www.learner.org/jnorth/images/imageshtml/earth-tilt.gif • http://costa-rica-guide.com/travel/index.php?option=com_content&task=view&id=365&Itemid=604&limit=1&limitstart=4 • http://www.windows.ucar.edu/tour/link=/earth/climate/cli_seasons.html • http://www.worldbook.com/features/seasons/assets/tilt4.gif • http://www.springboardmagazine.com/SpringImages/seasons.gif • http://www.nmm.ac.uk/upload/img/latitude.gif • http://www.astro.virginia.edu/class/oconnell/astr121/im/hours-of-daylight-v-date.jpg • http://en.wikipedia.org/wiki/Summer_Solstice

More Related