Moon Occurrences Eclipses Tides
Notes page:
What is an eclipse? An eclipse is an event during which one object casts a shadow onto another.
Two types of Eclipses Two types of Eclipses: Lunar Eclipse Solar Eclipse Eclipses happen because: The Sun, Moon and Earth occasionally line up causing an eclipse
Shadows of the Earth There are two parts of Earth s shadow that we will focus on, the umbra (UHM-bruh) and the penumbra (pih-nuhm-bruh) There is a third one, the Antumbra.
Words to Know Umbra the darkest part of the shadow during an eclipse (people in the umbra will see a total eclipse)
Words to Know Penumbra - the lighter part of the shadow during an eclipse (people in the penumbra will see a partial eclipse)
Earth moves between the Sun and the Moon Moon is in Earth s shadow this shadow darkens the moon Can only occur at a Full Moon About 2-3 lunar eclipses per year (Last up to 4 hours)
Images: Moon orbiting into shadows
Path of lunar eclipse (different view) Only in the umbra shadow will you have a total eclipse!
Total Lunar Eclipse in the middle of the umbra shadow
Why is it orange/red? Even though the Earth completely blocks sunlight from directly reaching the surface of the Moon, the Moon is still visible to the eye during a total lunar eclipse. This is because the Earth's atmosphere refracts sunlight and indirectly lights up the Moon's surface.
Notice the color based on where it is in the shadow path
Moon moves between the Earth and Sun The Moon s shadow covers part of the Earth Only happens during a New Moon Total solar eclipses are rare occurrences
Total Solar Eclipse the view Observers in the umbra shadow see a total eclipse (safe to view the Sun) Those in penumbra see a partial eclipse (NOT safe to look directly at Sun) Only lasts a few minutes Path of Totality about 10,000 miles long, only 100 miles wide
Photo of a Total Eclipse
Partial Solar Eclipse
You have 5 minutes to work in pairs to finish this page:
Answers:
Answers:
Solar:
Lunar:
Another Moon Occurrence Ocean Tides! Tides are very long-period waves in the ocean because of the forces of gravity from the sun and moon, and move toward coastlines. Water rises and falls every 12.5 hours This means that there are two high tides and two low tides every day
Tides happen every day Tides occur every day along coastal areas. In North America, tides fluctuate greatly Extremes in Alaska (west) and Novia Scotia (east) can be seen However, these tides are barely noticeable out in the ocean.
Tides
Tracking Tides Now, with the internet, you can find the tide for most areas.
Tidal Charts provide information about tides in a certain area, especially when low and high tide will be.
Why do we have tides? Tides are caused by the pull of Moon s gravity on Earth (and sometimes the sun as well) Two tidal surges a day, a low tide and a high tide
High tide: occurs in areas where side is facing Moon and the side away from Moon Known as Spring Tides Note write or draw this information on your notes page!
Low tide: occurs on sides of Earth Note write or draw this information on your notes page! Known as Neap Tides
The Moon s Gravity The Moon s gravity tugs on the Earth Tides occur mainly because of differences in how much the moon pulls on different parts of the Earth It pulls the most on the part of Earth closest, which raises the atmosphere, the oceans, and even the rocks (a little) It pulls the least on the part of Earth that s farthest away
High Tides and the Tide Cycle As Earth rotates, one high tide stays on the side of Earth facing the moon The second high tide stays on the opposite side of Earth Every location on Earth sweeps through those two high tides and two low tides in a 25-hour cycle
Make observations for neap and spring tides now!
Tides and the Lunar Cycle During New and Full Moon are Spring Tides greatest difference between high and low tide During First and Last Quarter - Neap Tides least difference between high and low tide
Spring Tide or High Tide The sun s gravity also pulls on Earth s waters During a New and Full moon - the Sun, Earth, and moon are nearly in a line (parallel) The gravity of the sun and the moon pull in the same direction The combined forces produce a tide with the greatest difference between low and high tide Occurs twice a month
The Sun, Earth and Moon are in a line
Neap Tides or Low Tides During First and Last Quarter moons - the line between the Sun, Earth, and moon is a right angle This arrangement produces a tide with the least difference between low and high tide (the size of the tide is lower)
The Sun, Moon and Earth are NOT in a line, but rather they are perpendicular
Animation:
Bay of Fundy (on the Atlantic coast, by Maine and Canada) Bay of Fundy Observations January 24, 2011 Famous for it s extreme tides! Fundy video
Tides video: Video link: https://www.youtube.com/watch?v=klwpf LfLFBI