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8E.4A.2
8.E.4A.2 Construct and analyze scientific arguments to support claims that the universe began with a period of extreme and rapid expansion using evidence from the composition of stars and gases and the motion of galaxies in the universe.

Essential Knowledge
The universe is composed of matter and energy. All of the matter in the universe now was in the universe when it formed. There is evidence to support that scientists are able to estimate the age of the universe in two ways
o by looking for the oldest stars
o Nebula (gas and dust) exist in space and are remnants from the formation of the universe.
o Stars undergo a life cycle based on the composition of the gases within them. As stars age the amount of hydrogen in the star changes, therefore changing the color and brightness of the star.
o by measuring the rate of expansion of the universe
o Astronomers determined the galaxy is expanding based on the color of light emitted from galaxies and stars. o As the universe expands and galaxies move apart, the wave-length of light emitted from those galaxies is stretched. This shifts the light toward the red end of the spectrum and is called “redshift”. The more distance or faint a galaxy the more rapidly it is moving away from Earth.
Extended Knowledge
o Knowledge of the movement of galaxies and stars has advanced as we have made developments in space technology.
o Students can use spectrometers to measure emission lines from stars.
o Students can develop models to show how expansion results in an increase in wavelength which produces red-shift. * Students can research additional resources regarding the evidence scientists use to support the argument that the universe is expanding as well as the age of the universe.
8.E.4B.1 Obtain and communicate information to model and compare the characteristics and movements of objects in the solar system (including planets, moons, asteroids, comets, and meteors).
Objects found in the solar system have characteristics based on surface features and atmosphere (if there is one).
These objects move via orbit/revolution and/or rotation.
Planets
 Planets may have either a terrestrial/rocky surface or a gaseous surface. Gaseous planets are
considerably larger than terrestrial planets.
 Planets may have rings or other unique surface characteristics.
 Movement of planets is based on revolution around the Sun and rotation on the planet’s axis.
Moons
 Moons are studied in relation to the planet they orbit. Not all planets have moons.
 Most are rocky bodies covered with craters, but some have unique characteristics.
 Movement of moons is based on revolution around their planets and rotation on their axis.
Asteroids
 Most asteroids are rocky bodies that orbit in a region in the solar system known as the Asteroid Belt
between Mars and Jupiter.
 They vary in size and shape.
 Movement is based on their revolution around the Sun.
 Some asteroids outside the asteroid belt have orbits that cross Earth’s orbit, which require scientists to
monitor their positions.
Comets
 Comets have a main body or head (ice, methane and ammonia and dust) and a tail that emerges as the
comet gets closer to the Sun during its orbit.
 The effects of the solar winds result in the tail always points away from the Sun.
 Comets have long, narrow, elliptical orbits that cause them to cross paths with other objects in the solar
system.
 Most comets originate from regions of the solar system that lie beyond the orbit of Neptune.
Meteors
 Meteors are chunks of rock that burn upon entering a planet’s atmosphere.
 Prior to entering the atmosphere the chunks of rock move about within the solar system and are known
as meteoroids.
 When the chunk of rock strikes the surface of a planet or moon it is known as a meteorite.
Extended Knowledge
 Factors affecting the appearance of impact craters include the size, mass, speed and angle of the falling
object.
 The solar system consists of the Sun and a collection of objects of varying sizes and conditions—
including planets and their moons—that are held in orbit around the Sun by its gravitational pull on
them.
 Planetary motions around the Sun can be predicted using Kepler’s three empirical laws, which can be
explained based on Newton’s theory of gravity.
 Students can research the likelihood that Earth will be struck by a large object from space, what might
be the outcome of such a collision (students can look at historical impacts as well as predict the results
of future impacts), what we are doing to identify those objects, and what we might be able to do to avoid
such collisions.
 Students can describe the unique characteristics of the planets and/or of the major moons that are found
in our solar system.
Students can research dwarf planets and argue from scientific information as to whether or not this new
classification is needed.
8.E.4B.2 Construct explanations for how gravity affects the motion of objects in the solar system and tides on Earth.
Tides and planetary orbits are caused by the pull of gravity.
Effects of Mass and Distance on Gravitational Force
 The more massive an object, the greater it’s gravitational pull.
 The closer the distance between objects, the greater the gravitational pull
 The gravitational pull between the Sun and the planets and between Earth and its Moon cause distinct
motions between and among these bodies
Effects of Gravity on Planetary Orbits
 The Sun’s gravitational attraction, along with the planet’s inertia (continual forward motion), keeps the
planets moving in elliptical orbits (Earth’s orbit is slightly oval) and determines how fast they orbit.  Planets nearer the Sun move/orbit faster than planets farther from the Sun because the gravitational
attraction is greater.
 When a planet is farther from the Sun, the gravitational attraction between them decreases and the planet
moves/orbits slower.
Effects of Gravity on Tides
 Since the Moon is closer to Earth than the Sun (distance), the Moon has the greatest pulling effect on
tides, the rise and fall of Earth’s waters.
 The Sun also pulls on Earth and
o can combine its force with the Moon causing even higher tides, spring tides
o or can be a right angles, pulling against the Moon’s pull, causing very little tidal change, neap
tides.
8.E.4B.3 Develop and use models to explain how seasons, caused by the tilt of Earth’s axis as it orbits the Sun, affects the length of the day and the amount of heating on Earth’s surface.
Earth’s axis remains pointed in the same direction at all times as the Earth revolves around the Sun.
 The combination of the revolution around the Sun and the fixed angle of the Earth’s axis result in the
following seasonal changes: temperature changes, angle of sunlight, number of daylight hours.
 As Earth revolves around the Sun, the tilt of its axis (23½ degrees) determines the amount of time that
the Sun is shining on a specific portion of Earth. The tilt remains at the same angle and points in the
same direction as Earth revolves around the Sun. This difference in the amount of time that an area
receives sunlight results in changes in the length of day.
 When the tilt of Earth is toward the Sun in a particular hemisphere, there is a longer length of day and
the season is summer.
 When both hemispheres are receiving the same amount of sunlight, the length of day and night is equal.
This occurs in fall/autumn and spring.
 When the tilt of Earth is away from the Sun in a particular hemisphere, there is a shorter length of day
and the season is winter.
 The combination of direct rays from the Sun that strike Earth at higher angles (closer to 90 degrees) and
more daylight hours causes the hemisphere of Earth tilted toward the Sun to have warmer temperatures.
 The combination of indirect rays from the Sun that strike Earth at lower angles and less hours of
daylight in the hemisphere of Earth angled away from the Sun have cooler temperatures.
Extended Knowledge
 At latitudes beyond 66.5 degrees north and south (the Arctic Circle and Antarctic Circle), there are
“days” and “nights” that last for a month or for months. During the “day” period, the Sun never fully
sets and during the “night” period the Sun never fully rises.
 The only region of the Earth that ever receives sunlight at 90 degrees is between the Tropics of Cancer
(23.5 degrees north) and Capricorn (23.5 degrees south).
 The changes in seasons affect living things in many different ways. These changes can stimulate living
things to enter dormancy or hibernation, enter into courtship behaviors, develop structures for
reproduction, and/or many other responses.
 Over the course of Earth’s history, the Earth’s axis has wobbled. This means that the Earth’s axis has not
always been pointed in the same direction. When combined with variations in the tilt of the Earth’s axis
and the distance the Earth is from the Sun, the result is an approximately 100,000 year cycle of ice ages.
 Migratory animals sense the change in the amount of daylight (photoperiod) and respond by migrating.
8.E.4B.4 Develop and use models to explain how motions within the Sun-Earth-Moon system cause Earth phenomena (including day and year, Moon phases, solar and lunar eclipses, and tides).
Essential Knowledge
All bodies in the solar system are in constant motion.
Day
 The Earth rotates on its axis as it revolves around the Sun. It takes approximately 24 hours, a day, for a
complete rotation to occur. This counterclockwise motion occurs from west to east, causing the Sun to
appear to rise in the east and set in the west.
Year
 While the Earth rotates on its axis, it is also revolving around the Sun. It takes 365 ¼ days, a year, for
this motion/orbit to occur.
 The Earth revolves around the Sun in an elliptical orbit.
Lunar Movement
 The Moon rotates on its axis and revolves around the Earth as the Earth revolves around the Sun.
 It takes about 27 Earth days for the Moon to rotate on its axis and about 29 ½ Earth days (month) for it
to revolve around the Earth.
 Because the Moon’s period of rotation on its axis and period of revolution around the Earth are nearly
the same, the same side of the Moon always faces Earth.
 Changes in the Moon’s position as it revolves around the Earth results in more or less of the sunlight
reflected form the Moon being visible when observing the Moon from the Earth. This causes the Moon
to appear to change shape.
Phases of the Moon
 New Moon- The Moon is positioned between the Sun and the Earth so that the side of the Moon that is
viewed from Earth is cannot be seen. Because of this, there appears to be no Moon in the night sky.
 Full Moon- The Sunlit portion of the Moon is facing the Earth while the Earth is positioned between
the Sun and Moon. The Moon is visible in the sky.
 The Sunlit portion of the Moon that is visible from Earth appears to either increases (waxes) or
decreases (wanes), as the Moon orbits the Earth.
 Crescent Moon-either waxing or waning; less than ½ of the Sunlit portion of the Moon is visible.
 Gibbous Moon-either waxing or waning; Greater than ½ of the Sunlit portion of the Moon is visible.
 First/Third Quarter-1/2 of the Sunlit portion of the Moon is visible.
o A first quarter follows the waxing crescent.
o A third quarter occurs when ½ of the Moon is visible.
Eclipses
 Eclipses occur when an object in space passes directly between two other objects or between the object
and the viewer.
 A solar eclipse occurs when the Moon passes directly between the Sun and Earth, blocking the Sun’s
light and casting a shadow over a certain area on Earth. This can only occur during a New Moon.
 A lunar eclipse occurs when Earth passes directly between the Sun and the Moon, blocking the Sun’s
light so that Earth’s shadow hits the Moon casting a shadow over the Moon. This can only occur
during a Full Moon.
 An eclipse does not occur at every New Moon and Full Moon because of the angle of the Moon’s orbit
around the Earth.
Tides
 Tides are the rise and fall of the surface levels of Earth’s ocean water caused by the gravitational effects
of the Sun and Moon on Earth. The effects of tides are most noticeable along ocean shorelines.
 As the Moon orbits Earth, the waters of Earth closest to the Moon bulge outward toward the Moon.
This bulge is the high tide. Another high tide occurs on the opposite side of Earth. Low tides occur in
the areas between the two high tides.
 As the Earth rotates on its axis, any given location will rotate into and out of the tidal bulge. This
results in the changes between high and low tides over the course of 24 hours.
 When the Sun and the Moon are aligned so that the Moon is between the Sun and the Earth (New
Moon) or the Earth is between the Sun and the Moon (Full Moon) high tides are higher and the low
tides are lower. These are called spring tides. When the Sun and the Moon are at right angles to each
other (first and last quarter), lower high tides and higher low tides are experienced. These tides are
called neap tides.
Extended Knowledge
Scientists can study the top layer of the Sun during some solar eclipses. The Moon blocks the brightest rays of
sunlight. This makes it easier for scientists to see the top layer of the Sun.
If the Earth had no atmosphere, then the Moon would be completely black during a total eclipse. Instead, the
Moon can take on a range of colors from dark brown and red to bright orange and yellow. The exact appearance
depends on how much dust and clouds are present in Earth's atmosphere. Total eclipses tend to be very dark
after major volcanic eruptions since these events dump large amounts of volcanic ash into Earth's atmosphere.
The orbit of the Moon around the Earth is inclined about 5.1 degrees when compared to the Earth’s orbit around
the Sun. This is the reason that eclipses do not occur with every New and Full Moon; the shadows do not line
up.
The Moon orbiting the Earth affects the timing of high and low tides. This results in these tides occurring at
different times every day,
8.E.4B.5 Obtain and communicate information to describe how data from technologies (including telescopes, spectroscopes, satellites, space probes) provide information about objects in the solar system and the universe.
Astronomers use telescopes, satellites, space probes, and spectroscopes to make observations and collect data
about objects inside the solar system and outside the solar system. These tools and the associated technology
that allow astronomers to analyze and interpret the data help scientists learn about the solar system and about
the universe.
Telescopes
 Refractor telescopes use convex lenses to bend and focus light rays to produce images of objects in
space
 Reflector telescopes use mirrors to focus light rays to produce images of objects in space.
 Radio telescopes receive radio waves emitted from objects in space, including waves from very distant
stars and galaxies. Then the radio waves are used to produce images of the objects from sound waves.
Radio telescopes receive information in any weather and during day or night.
 Other telescopes “read” infrared or x-ray signals but have to be placed where Earth’s atmosphere does
not block or absorb the signals.
Satellites and Space Observatories
 Satellites are placed in orbit around Earth with special instruments and telescopes that collect
information from space. The information is sent back to Earth where it is interpreted.
 Space Observatories are telescopes or other instruments that have been launched into outer space to
collect data on distant planets, galaxies, and other celestial bodies. The Hubble Space Telescope is an
example of a space observatory.
 Data gathered from satellites and space observatories are not hampered by Earth’s atmosphere.
Space probes
 Space probes contain instruments to collect data and travel out of Earth’s orbit to explore places that
would be too dangerous for astronomers; the instruments that a probe contains depends upon the space
mission.
Spectroscopes
 Spectroscopes collect the light from distant stars and separate that light into bands of different colors;
by studying these bands, astronomers identify the elements in a star.
8.E.4B.6 Analyze and interpret data from the surface features of the Sun (including photosphere, corona, Sunspots, prominences, and solar flares) to predict how these features may affect Earth.
 The photosphere is the visible surface of the Sun that emits the light that we see. It is the lowest layer
of the Sun’s atmosphere.
 The corona, the outer most layer of the Sun’s atmosphere, also emits light but is only visible as a white
halo during a solar eclipse.
 Sunspots appear as dark spots on the photosphere. They are actually moving areas of magnetic activity
with temperatures that are cooler than the area of the photosphere in which they are located.
Astronomers study Sunspot cycles to learn how changes in solar activity affect life on Earth.
 Prominences are bright arch-like loops that may erupt from the photosphere into the corona. Often
associated with Sunspot activity, they release large amounts of energy into outer space.
 Solar flares occur near Sunspots and are sudden, intense explosions that result in changes in brightness
when magnetic energy is released. The charged particles released by solar flares are often detected in
Earth’s atmosphere. The energy released from solar flares can cause damage to the International Space
Station, disrupt radio and electrical transmissions on Earth, and cause displays of bright lights, auroras,
that appear to “dance” in the skies near the North and South Poles.
Extended Knowledge
Students can research how Sunspots, prominences, and solar flares are related.
Students can explore solar wind and describe how it can affect conditions on Earth and cause atmospheric
phenomena.
Students can describe how these activities can release energies and particles that can interact with living things
and man-made objects.
WOAs Feb 5
My Planet Diary pg 224
Feb 7
Roper Mountain Science Center Trip
Feb 8
Piedmont Technical College Trip
Feb 20
Benchmark Testing
Feb 21
Benchmark Testing
Feb 22
Benchmark Testing
Missing Work
Tide Interpret and Experiment Station
Oreo Moon Phase Model