D4
It is expected that students will:
Explain astronomical
phenomena with reference to
the Earth/moon system
Students who have fully met the prescribed learning outcome are able to:
- describe the formation of the Earth’s moon, with reference to
supporting evidence - describe the significance of Earth’s rotation, revolution, and
axis tilt (e.g., seasons, day/night) - describe the celestial sphere in relation to constellations and
their locations - explain the apparent motion of constellations, planets, the
Sun, the moon, asteroids, and comets - explain and illustrate solar and lunar eclipses (moon phases)
photo: blondie38@morguefile
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RESOURCES
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Planning for Assessment / Assessment Strategies
Ask students to brainstorm ideas as to why
Earth has such a large moon compared to its
size (in relation to the other terrestrial
planets). Explain that many hypotheses have
emerged over the years, but current thinking
is that during the early stages of formation, a
large body collided with Earth, sending a
large molten chunk of the mantle into orbit
around the Earth, eventually forming the
moon.
Given a list of several scenarios for explaining the
formation of the Earth-Moon system, have
students
- list the relative strengths or weaknesses of
each hypothesis
- rank the credibility of each hypothesis and
explain the rationale for their ranking
Note that the list is subjective, and a student
should not be penalized for their choices so long
as the explanations are reasonable.
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Ask students the following questions:
- What causes day and night?
- What causes seasons?
- What causes stars and constellations to
change position in the sky throughout the
night?
- Except for circumpolar constellations,
why don’t we see the same constellations
at night throughout the year?
- Why doesn’t the north star change
position (i.e., except over thousands of
years)?
Explain that all of these apparent motions and
phenomena are due to three factors: Earth’s
revolution around the Sun, its rotation on an
axis, and the tilt of its axis relative to its
orbital motion.
Assess students on their ability to correctly list
and explain the factors that cause each
phenomena to exist:
- day and night: rotation
- seasons: all three factors
- changing position of stars/constellations:
rotation
- changing view of constellations throughout
the year: revolution and rotation
- stationary north star: tilt of axis
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Show students a star map. Have them locate
and identify some major stars and
constellations, including: Polaris, the Big
Dipper (Ursa Major), the Little Dipper (Ursa
Minor), Cassiopeia, Orion, Deneb, and one or
two zodiac constellations. Then, have
students research which celestial bodies are
visible in early evening at their present date.
Finally, organize a night gathering in early
fall or late winter, when the Sun is fully set in
the evening on a clear night. Bring a good
telescope and have students locate and
observe various stars, constellations and
planets, including the one they were expected
to see. Have students construct field notes
that include a sky map illustrating direction
and labelling several significant objects
observed.
Students will be expected to produce a detailed
set of notes describing the location of the
gathering, date and time, as well as a well-drawn
map accurately showing correct locations of the
objects observed, relative to north.
RESOURCE:
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Shine a bright light on a golf ball against the
blackboard. Point out the dark interior
shadow and the more faded outer shadow of
the golf ball. Draw a ray diagram illustrating
the full interior shadow as well as the partial
outer shadow. Next, ask students to relate
these shadow regions to total and partial
eclipses of the Sun and Moon by drawing ray
diagrams and noting the Sun-Earth-Moon
positions in each case.
Assess students’ ability to draw
- a solar eclipse, with Sun, Earth, and Moon in
correct positions, and rays showing regions of
total and partial eclipse
- a lunar eclipse, with Sun, Earth, and Moon in
correct positions, and rays showing regions of
total and partial eclipse
