ESSENTIAL QUESTIONS:
1.Can you describe how the positions of the Sun, Moon, and Earth determine the type of eclipse? 2.Can you model how the shadow cast in an eclipse causes partial and total eclipses? Eclipse •The total or partial obscuring of a planet, star, or moon by another celestial object •The passing of a celestial object into the shadow of a planet, star, or moon •Types: solar and lunar Solar Eclipse •Occurs when the Moon passes between the Earth and the Sun totally or partially obscuring Earth’s view of the sun •The moon casts a shadow on part of the Earth. •Occurs during the new moon phase Occurs during daylight Lunar Eclipse •Occurs when the Earth passes between the Moon and the Sun. •The Earth casts a shadow on the Moon blocking all or a portion of it. •Occurs during the full moon phase Occurs at night Total Solar Eclipse •When the moon blocks out the Sun entirely Partial Solar Eclipse •When the moon blocks out a portion of the Sun Annular Eclipse •When the Moon is at its furthest point in orbit •Its shape will not cover the Sun completely. •This is when you can see a thin ring of light emerging from the outside rim of the moon. Total Lunar Eclipse •Occurs when the moon completely passes into the darkest part (umbra) of Earth’s shadow •Only occurs during full moon phase •Occurs at night Partial Lunar Eclipse •Occurs when the moon passes into the lightest part (penumbra) of Earth’s shadow. •Occurs only at Full moon phase •Occurs at night Umbra •The darkest part of a shadow •The cone-shaped region of full shadow cast by Earth and the Moon during an eclipse. Umbra/Solar Eclipse •When the umbra from the Moons shadow touches Earth, you have a total solar eclipse. •Point C in the diagram Umbra/Lunar Eclipse •The entire disk of the Moon is darkened as it passes through the umbra •The area of partial shadow surrounding the total shadow (umbra) cast by the Earth or Moon. Penumbra/Solar Eclipse •When the penumbra of the Moon’s shadow touches Earth you have a partial solar eclipse •Point B in the diagram Penumbra/Lunar Eclipse •When the penumbra of the Earth’s shadow touches the Moon you have a partial/penumbral lunar eclipse ESSENTIAL QUESTIONS:
1.Why does the moon look different every night? 2.Can you make predictions about the Moon’s appearance? Lunar Cycle – the change in appearance of the Moon as it makes one full revolution around the Earth. New Moon •The first phase of the Moon and it appears unlit from Earth. •The Moon is between the Earth and the Sun. Waxing Crescent •The lighted part of the Moon as seen from Earth is increasing. •The light on the right is new and bright. •Think about the shape of a crescent roll. First Quarter •The Moon is one quarter of the way through its cycle. •From the Earth it appears to be half lit on the right. Waxing Gibbous •From the Earth, the Moon appears to be more than half lit on the right. •The light is shaped like a football. Full Moon •From the Earth the Moon appears fully lit. •The Earth is between the Sun and the Moon. Waning Gibbous •From the Earth, the Moon appears to be more than half lit on the left. The lighted part is now decreasing Third or Last Quarter •The Moon is three-quarters of the way through its cycle. •From the Earth it appears to be half lit on the left. Waning Crescent •The lighted part of the Moon as seen from Earth is decreasing on the left. •The shape of the light is crescent. ESSENTIAL QUESTIONS:
1.What causes day and night? 2.What causes the seasons to change? Rotation •The action of spinning on an axis •Causes night and day •1 Earth day = 24 hours •Ex. Ferris wheel, pinwheel Revolution •The movement of one object around another •Earth orbits the Sun •The Earth is at a constant tilt of 23.5º •Revolution + Tilt = Seasons 1 year = 365 ¼ days Summer Northern Hemisphere •The northern hemisphere is tilted toward the Sun. •Most direct sunlight (focused light) •Longer days and shorter nights. •North pole has constant daylight Fall Northern Hemisphere •The axis is not pointed towards or away from the Sun. •Equal sunlight in both hemispheres •Equal length days and nights at the equator Winter Northern Hemisphere •The northern hemisphere is tilted away from the Sun. •Most indirect sunlight •Shorter days and longer nights •South pole has constant daylight Spring Northern Hemisphere •The axis is not pointed towards or away from the Sun. •Equal sunlight in both hemispheres •Equal length days (12 hours) and nights (12 hours) at the equator Seasons Southern Hemisphere •Opposite of northern hemisphere •Ex. If it’s summer in Dallas, then it’s winter in Rio de Janeiro. Solstices •The longest or shortest days of the year •The Sun reaches its highest or lowest point in the sky at noon. •Summer Solstice – about June 21st •Winter Solstice – about December 21st Equinoxes •Day and night are equal at the equator •Vernal equinox – about March 20th •Autumnal equinox – about September 22nd SCIENCE 8:
Tides •The alternate rise and fall of the oceans •Tides and waves are not the same thing •Tides rise and fall about every 12 hours due to the rotation of the Earth •2 high tides and 2 low tides every 24 hours Gravity and Tides •Gravity of the Moon and Sun cause the tides •The Moon is closer to Earth and has a much greater impact on the tides than the Sun. Low Tide •Beach and environment exposed Organisms have adapted to long periods with limited water High Tide •Environment becomes flooded with ocean water Organisms have adapted to long periods of immersion in saltwater Spring Tides •The Sun, Earth, and Moon are in a straight line. •Largest difference between high and low tides New or Full Moon Neap Tides •The Sun, Earth, and Moon form a ninety degree angle. •Smallest difference between high and low tides •1st or 3rd Quarter Moon |
Erik E. Mason
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