1. Eclipses and Tides Entry 9

2. What is an Eclipse? When Earth or the Moon temporarily blocks the sunlight from reaching the other.

3. Two Types of Eclipses- 1. Solar Eclipse- Moon comes between Sun and Earth and casts a shadow on Earth. 2. Lunar Eclipse- Earth comes between the Sun’s light and the moon and blocks the light from the moon.

4. Shadows of Eclipses- 1. Umbra- Darkest part of a shadow. 2. Penumbra- lighter portion of a shadow.

5. Solar Eclipse A solar eclipse can only occur when the moon is in its “new moon” phase.

6. Total and Partial Solar Eclipses

7. Lunar Eclipse A lunar eclipse can only occur when the moon is in its “full moon” phase.

8. Total Lunar Eclipse  Lunar eclipses occur because of the moon’s tilted orbit and only occur a couple times in a year  Feb 20, 2008- partial starts 8:43 total starts 10:00

9. What is a tide?  The rise and fall of the sea level.  Caused by the gravitational pull of the Sun and the Moon.  There are 2 high tides and 2 low tides daily.

10. Affect of Gravity on tides-  The moon’s gravity exerts a strong pull on the Earth causes the water to bulge outward at places.  The bulges of water are high tides & non-bulges are low tides.

11. Spring Tides-  When there is the greatest difference between high and low tides (high- highs and low-lows).  Occurs when moon is in a straight line with sun and Earth= New moon and Full moon.

12. Neap Tides-  When there is the little difference between high and low tides (almost equal).  Occurs when moon is at 90° with sun and Earth= 1 st and 3 rd quarter.