The Moon It's Just a Phase It's Going Through...
Moon • Our planet's large natural satellite, the Moon, is the easiest astronomical object to observe. • The only "scientific instrument" you'll need at first is a pair of eyes. Picture from NASA
The Moon's Orbit • Rotation • Moon is spinning on its axis • Revolution • The moon orbits around the Earth • It takes the moon approximately one month to go around the Earth.
Why do we never see the DARK SIDE? • Synchronous Rotation is the reason we never see the dark side of the moon. • The Moon has become "locked" into a special kind of motion around the Earth. • It rotates on its axis at the same pace as it revolves around the Earth • As a result, the Moon keeps the same face toward us throughout its orbit.
Phases • The illuminated side of the moon always faces the sun.
E New Moon What we see • New moon occurs when the moon is between the sun & the Earth. • The entire dark side of the moon is facing the Earth. • The New Moon rises and sets with the sun. What is happening from above. Sunlight
E Full Moon What we see • The full moon occurs when the Moon & the Sun are on opposite sides of the Earth. • The entire illuminated side of the moon is facing Earth. • The Full moon rises and sets opposite of the sun. What is happening from above. Sunlight
Full Moon (you do not have to write this page) • The full moon is given different names, depending on when it appears. For example, the "Harvest moon" is the full moon that appears nearest to the Autumnal Equinox, occurring in late September or early October. Some other full moon names (by month) include • January Moon After Yule, Wolf Moon, or Old Moon • February Snow Moon or Hunger Moon • March Sap Moon, Crow Moon, or Lenten Moon • April Grass Moon or Egg Moon • May Milk Moon or Planting Moon • June Rose Moon, Flower Moon, or Strawberry Moon • July Thunder Moon or Hay Moon • August Grain Moon or Green Corn Moon • September Fruit Moon or Harvest Moon • October Harvest Moon or Hunter's Moon • November Hunter's Moon or Frosty Moon, • December Moon Before Yule or Long Night Moon.
Blue Moon • When there is more than one full moon in a month, the second moon is called a blue moon. • A blue moon happens every two years on average. • The phrase, “Once in a blue moon” means very rarely or very seldom or almost never.
E First QuarterMoon What we see • The First quarter moon occurs when the moon is halfway between new and full. • As seen from the Earth, half the moon’s disk is illuminated. What is happening from above. Sunlight
E Third QuarterMoon What we see • The Third or last quarter moon occurs halfway between the full moon & the new moon. • As seen from the Earth, half the moon’s disk is illuminated. What is happening from above. Sunlight
Waxing • When the moon is between new & full, the visible part of the moon is increasing. • This is called waxing • “Light on the right, it’s getting bright” in the Northern Hemisphere
Waning • When the moon is between full & new, the visible part of the moon is decreasing. • This is called waning. • The illuminated part is on the left in the Northern Hemisphere.
E Crescent Moon Full Moon • When the moon is between New & 1st Quarter it is called a waxing crescent. • When the moon is between 3rd & New it is called a waning crescent. 3rd Quarter 1st Quarter Waning Crescent Waxing Crescent New Moon Sunlight
E Gibbous Moon Full Moon Waning Gibbous • When the moon is between 1st Quarter & Full it is called a waxing gibbous. • When the moon is between Full & 3rd it is called a waning gibbous. 3rd Quarter 1st Quarter Waning Crescent Waxing Crescent New Moon Sunlight
TIDES • Tides occur because of the pull of gravity of the Moon and the Sun on the Earth's oceans. • Because the Moon is closer to the Earth, it has the greatest effect on our tides. • There are approximately 2 high tides and 2 low tides every 24 hours.
Spring Tides • Spring tides occur at New Moon and Full Moon when the Sun, the Moon and the Earth are all in line. • This forms extremely high high-tides and extremely low low-tides
Neap Tides • Neap tides occur at First Quarter and Third Quarter, when the Sun, the Earth and the Moon are at right angles. • This forms low high-tides and high low-tides.
Sun – Moon – Earth review • The Moon revolves around the Earth • The Earth revolves around the Sun • The Moon doesn’t shine on its own; it reflects sunlight back to Earth
Phases: New Waxing Crescent 1st Quarter Waxing Gibbous Full Waning Gibbous 3rd Quarter Waning Crescent New
The Sun shines on the Moon. • When the sunlight reflects off the Moon’s far side, we call it a New Moon • When the sunlight reflects off on the Moon’s near side, we call it a Full Moon • Between New and Full, we see different parts of the daytime side of the Moon.
Eclipses • The Sun and Moon occasionally line up so that we have an eclipse.
When the Earth’s shadow covers the Moon, we have a lunar eclipse • Lunar Eclipses only happen during a full moon
Why is the moon red during a lunar eclipse? • The Earth’s atmosphere filters some sunlight and allows it to reach the Moon’s surface • The blue light is removed—scattered down to make a blue sky over those in daytime • Remaining light is red or orange • Some of this remaining light is bent or refracted so that a small fraction of it reaches the Moon • Exact appearance depends on dust and clouds in the Earth’s atmosphere
Solar Eclipse • When the Moon’s shadow covers part of the Earth • Only happens at New Moon • Three types: Annular, Partial, and Total
Solar Eclipse • The Sun is about 400 times larger than the Moon, but it is also about 400 times further away. • As a result of this coincidence, the Moon can completely cover the Sun, producing a total solar eclipse.
Solar Eclipse • A total solar eclipse occurs about once every 18 months somewhere in the world. • At any given location, a total solar eclipse occurs once every 360 years. • The next total solar eclipse in the U.S. will be Aug. 21 2017.
Solar Eclipse • Observers in the “umbra” shadow see a total eclipse; can see the corona (outer part of 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