Remember that as the Earth revolves around the Sun, its axis points in the same direction. This is why during some seasons, the northern hemisphere gets more direct sunlight, and in others, the southern hemisphere gets more sunlight.
Solstice: The longest day of the year (for Northern hemisphere = June 21) The shortest day of the year (for Northern hemisphere = December 21)
Solstice: Summer Solstice: “The longest day of the year” means when the Earth is getting the most direct sunlight for the longest period of time - Means that the Northern hemisphere is facing as close to the sun’s direct rays as possible
Summer Solstice 2012: In Washington, D.C. Sunrise: at 5:43 am Sunset: 8:37 pm Length of daylight hours: 14 hours, 54 minutes
Solstice: Winter Solstice: December 21 st “the shortest day of the year” –this means that the Northern hemisphere is getting the least amount of direct sunlight during daylight hours – Meaning the Northern Hemisphere is tilted as far away from the sun’s direct rays as possible
Winter Solstice 2012: In Washington, D.C. Sunrise: 7:24 am Sunset: 4:50 pm Length of daylight hours: 9 hours, 26 minutes
An equinox is when the sun is directly hitting the equator, which means that the Northern and Southern hemispheres are getting about the same amount of sunlight Both the Northern and Southern hemispheres have 12 hour days (equal amount of day and night)
Equinox Fall Equinox: September 21 (in Northern Hemisphere) – first day of Fall Spring Equinox: March 21 (in Northern Hemisphere) –first day of Spring
Note: A season cannot officially change without a solstice or an equinox!
Challenge Trivia: If during the winter, the Northern Hemisphere is facing away from the sun and does not get direct sunlight, why do we still have daylight during those months?
Answer: Rotation! Remember that while the Earth is revolving around the sun every 365 days, it is rotating on its own axis every 24 hours! So for about 12 hours, the planet still is exposed to daylight, just NOT at a direct angle.
Rotation Counterclockwise! THE OPPOSITE OF HOW A CLOCK’S HANDS MOVE
Did you know the seasons influenced how we count days, months, and years? A year is 365 ¼ days because people noticed that there were 4 seasons With each season change, the moon went through its full cycle 3 times 4 season x 3 moon cycle per season = 12 months
Bill Nye http://www.youtube.com/watch?v=C2C2Jy2T Aew http://www.youtube.com/watch?v=C2C2Jy2T Aew