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Happy Haunted Homeroom October 9, 2012. Today is Tuesday, you have academic and I.S. with your Period 2 teacher. October 9, 2012 – WARM-UP Which of the following four diagrams most accurately depicts the Earth's orbit around the Sun?. Take out notes page 17.
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Happy Haunted HomeroomOctober 9, 2012 Today is Tuesday, you have academic and I.S. with your Period 2 teacher
October 9, 2012 – WARM-UP Which of the following four diagrams most accurately depicts the Earth's orbit around the Sun?
Take out notes page 17 9 The Solar System from “Overhead” • 91,369,000 miles on Jan 4 (minimum) • 94,776,000 miles on July 4 (maximum) • average distance is 92,918,000 miles • Varies +/- about 2% from a perfect circle
When is the Earth closest to the Sun? • Winter • Spring • Summer • Fall
HMWK – page C27 page 18 in notebook • What causes day and night? As Earth rotates, different areas face away and toward the sun.
HMWK – page C27 2) How are the time zones organized to help us know times around Earth? There is a difference of one hour between each time zone.
HMWK – page C27 3) How can you tell the difference between summer and winter by the sun? The sun is higher above the horizon in the summer, and it remains there longer each day than in the winter.
HMWK – page C27 4) How is the sun a source of energy for Earth? Light from the sun is needed to grow plants. All other life gets the Sun’s energy indirectly. The sun also provides the energy in fuels and energy for the water cycle. Earth absorbs some energy from the sun and changes it to heat that warms water, land , and the air.
Note Check • The Earth orbits the Sun in ___________(revolves) • The Earth spins around _______ each day (rotates) • The Moon orbits the Earth about once a month (revolves)
BRAIN POP! http://www.brainpop.com/science/weather/seasons/ http://www.youtube.com/watch?v=ndlQNicOeso&feature=related
Kinesthetic Seasons • Page 19 in notebook
POLARIS??? Polaris - commonly known as the North Star is very close to the north celestial pole
Solstices and Equinoxes Equinox: An equinox is when the length of day and night are approximately equal Solstice: A solstice is either of the two times of the year when the sun is at its greatest distance from the equator. Ecliptic Plane Spring Equinox Winter Solstice Fall Equinox • Spring Equinox ~ March 21 • Summer Solstice ~ June 21 • Fall Equinox ~ September 22 • Winter Solstice ~ December 21. Fall Solstice
Solstices and Equinoxes The dates of the equinoxes and solstices are only approximate dates. • The actual length of a year is about 365 ¼ days (365 days, 5 hours, 49 minutes), not exactly 365 days. We have to add an extra day to a year every four years to keep the seasons synchronized with the seasons (leap year). Over a longer period of time, we need to skip a leap year to compensate the extra minutes we add in every leap year to keep the calendar in sync.
Solstices and Equinoxes Some exceptions to this rule are required since the duration of a solar year is slightly less than 365.25 days. Years that are integer multiples of 100 are not leap years, unless they are also integer multiples of 400, in which case they are leap years.[3][4] For example, 1600 and 2000 were leap years, but 1700, 1800 and 1900 were not. Similarly, 2100, 2200, 2300, 2500, 2600, 2700, 2900 and 3000 will not be leap years, but 2400 and 2800 will be.