phases & eclipses. full new quarter crescent
TRANSCRIPT
A Full Cycle
Start with a New Moon Light travels from Right to Left (←) Getting Full: Waxing Getting New: Waning
What causes the phases?
Light from the Sun – AT AN ANGLE!
Activity: Place the Moon phases in the correct location around the Earth, relative to the Sun.
=
How Long does it take the Moon to go through a cycle?
SYNODIC
One full Phase Cycle New to New Moon
29.5 Days(4-ish weeks)
SIDERIAL
360° Around the Earth NOT the same as a
phase cycle!
27.3 Days(a little less)
Why is Siderial shorter than Synodic? Because the Earth is moving! The Moon must play “catch up” to
return to the New Moon position..
Moons of the Month
January: Old Moon or “Moon after Yule”
February: Snow/Hunger/Wolf Moon
March: Sap/Crow/Lenten Moon
April: Grass/Egg Moon May: Planting/Milk Moon June: Flower/Strawberry
Moon
July: Thunder/Hay Moon
August: Grain Moon September: Harvest
Moon October: Hunter’s
Moon November: Frosty
Moon December: “Moon
Before Yule” or Long Night Moon
BTW: What is a BLUE Moon?
The second of two full moons in one month.
Only happens once every 2-3 years
Not actually blue…
Next one will be on: July 31st, 2015!
If the Moon & Earth line up twice a month, why don’t they block each other?
The orbit of the Moon is at a 5° tilt from the Earth/Sun orbit.
Very rarely, all three bodies actually line up…
Eclipses! Eclipse: “To obscure”
LUNAR
The Moon is Eclipsed by the Earth
The Earth’s shadow falls on the Moon
SOLAR
The Sun is eclipsed by the Moon
The Moon’s shadow falls on the Earth
Lunar Eclipses
The Earth casts partial and full shadow .
Penumbral Eclipse: Moon passes through the Penumbra.
Partial Eclipse: Part of Moon passes through the Umbra, a chunk is in shadow.
Total Eclipse: Entire Moon passes through the Umbra
Why does the Moon turn red? Light from the Sun is still hitting the Moon It is being refracted through the Earth’s
atmosphere Only long wavelengths can bend around the Earth
and pass through the atmosphere All the world’s Dusk & Dawn light!
Solar Eclipses
The Moon casts partial and full shadow .
Partial Eclipse: Observer is in the Penumbra
Total Eclipse: Observer is in the Umbra
You have to be lucky to be in the path of a solar eclipse!
The path of the eclipse is small and travels fast! The shadow moves across the face of the Earthat 1050 mph! Most solar eclipses last under 7 minutes.
Annular Eclipse!
The Moon’s distance from the Earth changes slightly over time
IF the Moon is particularly farther away from the Earth during a solar eclipse…
How often do Eclipses occur?
Solar: 2-5 times a year
Lunar: up to 3 times a year, sometimes none
NASA’s Eclipse Tracker