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Introduction:
Ancient civilizations attached much importance
to sun, moon and star watching. The motion of these celestial bodies
was used to determine both agricultural and religious events. These
observations provided practical information for planting and harvesting
crops and preparation for seasonal changes. The astronomy also indicated
when rituals would be practiced, and war should be fought.
Mayan civilization had a very sophisticated understanding of celestial
motion. The Sun, Moon, and Venus were particularly important to their
cosmology. The Mayans attached a great deal of importance to the Zenial
passage when the sun would be directly overhead. Since most Mayan
cities lie south of 23 degrees North, the sun would be directly overhead
twice a year near to the solstices. The Mayans also worshipped the
Milky Way and had a sophisticated understanding of the ecliptic. The
Mayans, like all ancient civilizations, had a geocentric view of the
universe. The Earth was the fixed location from which to watch the
moving objects in the sky.
Their astronomical observations were included in a complex calendar.
The ritual calendar was composed of 260 days. 260 days is the
length of time Venus appears as a morning star and then 50 days later
as an evening star. Venus was closely watched by the Mayans and was
central to their mythologies of death and resurrection. The vague
calendar contained 365 days, comparable to our year and ran
concurrently with the 260 day calendar. In addition, the Mayan calendar
had a lunar component. The lunar count alternated between 29
and 30 days, thus coming close to the lunar synodic period of 29.5
days. The Mayans made accurate predictions of eclipses.
The methodology of these ancient astronomers predates the scientific
methods developed by Galileo and Newton. However, the methods used
by the Mayans, Babylonians and others laid the foundation for modern
astronomy. The ancient astronomers used naked eye observations, recorded
systematic data over time and used the observed patterns to make accurate
predictions. These practices are part of modern astronomy today.
Today's
astronomy rests on the observations and practices of these ancient
cultures. By making observations using simple tools, students will
not only replicate some of the Mayan observations, they will also
get a deeper understanding of the natural cycles they are part of.
Prior Knowledge:
•Students
should know that the Sun is the center of solar system and that the
Earth and other 8 planets revolve around the Sun.
•
Students should know latitude and longitude measurements.
•
Students should know the location of the equator, North Pole, South
Pole and Tropics.
•
Students should know the difference between revolution and rotation.
Big Idea/Theme/Essential Questions:
1.
How do the Sun, Moon and Earth move in relationship to one another?
2. How do we identify the patterns of movement of the Sun, Moon and
Earth?
3. How does the motion of the Sun and Moon relate to events on Earth?
4. How did ancient civilizations use knowledge of these movements
to build their civilizations and cultures?
Lesson Objectives:
Students will
•
Reflect on the differences between modern astronomy and ancient astronomy.
•
Model direct
observations of the motion of the sun and moon in a similar fashion
to Mayan astronomers.
•
Draw conclusions
about the sun and moons motion and position in relationship to Earth
based on their observations.
•
Model the
ecliptic and analyze the position of the Sun and Earth relative to the
constellations.
•
Connect Mayan
astronomy to their architecture, myths, calendar and agriculture.
Length of Lesson:
5
periods
Opening Activity:
Literacy Strategy
Graphic Organizer- T Chart
Students make a T-chart listing the differences between ancient civilizations
and modern civilization, including differences in how we do astronomy.
Students use science and social studies books to assist them. Possible
answers
T-Chart
After brainstorming,
explain to students that they will be studying the heavens in similar
ways as the ancient Mayans. Share some of the information from the
introduction to explain the significance of astronomy to the Mayans.(see
attachment).
Cross-curricular Connection Activity:
The
Mayan View of Earth: The Mayans viewed the Earth as flat and four
cornered, with one corner in each cardinal direction. Each direction
had a color: red for east, white for north, black for west, yellow
for south and green for the center. The sky was supported by four
trees, one in each corner and one at the center. The trees were all
different colors. The Earth was on the back of a giant crocodile resting
in a pool of water lilies. The crocodile's counterpart in the sky
was a double-headed serpent. This is probably because the Mayan word
for sky was close to the Mayan word for snake. Heaven had 13 layers.
Each layer was associated with a different god. The underworld had
nine layers, each associated with a Lord of the Night. The underworld
was a cold and unhappy place. Most Mayans went to the underworld after
their death (from
http://www.astronomy.pomona.edu/archeo/index.html)
The
Way Mayans Viewed the Earth image
Procedure:
Have students fill out the chart while teachers discuss how Mayans
viewed the earth.
Activity 1: Tracking the Sun’s Movement
Introduction:
Many different civilizations used a simple tool, a
stick oriented perpendicular to the ground, to record and observe
the Sun’s progress by observing the shadow of the stick. This
shadow casting stick is called a gnomon. Because the Mayans
and other ancient civilizations only used their eyes to observe the
Sun and other objects, they relied on fixed locations to give them
information about the changes in motion and to find patterns
Part A
(In class)
Materials:
For each student
•
a toothpick
•
index card
•
tape
•
Elmer’s glue or small amount of modeling clay
•
flashlights
(one per team)
•
light sockets with bulbs (one per team if possible)
Procedure:
1. Fold a corner of the index card on the diagonal
and cut off the hanging edge to make a square.
2. Draw the two intersecting diagonals to find the center and tape,
glue or use clay to attach the toothpick perpendicular to the card’s
surface.
3. Use a flashlight to shine a light on the toothpick from different
directions and angles. Observe changes in the shadow cast.
4. Make sketches and notes about what you observed.
5. Using the light bulb and socket, orient your toothpick card on
a flat surface. Make a mark on the side facing the bulb. Now move
the card around the bulb, keeping the correct orientation. Carefully
record changes in the shadow.
6. Tilt the index card at about a 20 degree angle, pointing the toothpick
towards the bulb; again move the card around the bulb. Carefully record
your observations.
Reflections and Summary:
Have students individually respond to the following writing prompt:
Explain what happened in your model. How did this activity model the
relationship of the Sun and Earth? What part of the model was the
Sun? the Earth? What conclusions can you come to about the Sun/Earth
relationship from this model?
After students write their reflections, have them share in their teams
and then conduct a whole class discussion.
(Additional activities and explanations of the use of sundials and
gnomons can be found at Me and My Shadow: Making the Earth Sun Connection
http://www.wsanford.com/~wsanford/exo/sundials/shadows.html)
Part B: (outside, minimum of two days)
Materials and Preparation:
•Meter
sticks or dowels anywhere from 18 cm. to one meter, either empty gallon
water or milk containers with sand or gravel in them or for small
sticks, empty soup cans with plaster of Paris to set sticks in. If
you use plaster of Paris, make it the day before so that the dowels
are set. The stick should be as close to perpendicular to the ground
as possible or alternatively, each group of students has a straw attached
with some modeling clay to the center of a square of cardboard. Make
sure the cardboard or tag board piece is big enough so that the shadow’s
end will be on it.
Procedure:
a) Observing the actual movement of the Sun, by observing its shadow
This activity can be done whole class with one meter stick, or students
can work in teams with meter stick gnomons or using the straw gnomons.
The recording can be done directly on the asphalt with chalk or paint,
if permitted to do so. Alternately, you can put big pieces of butcher
paper under the gnomon. If students are working in teams with the
cardboard, they can record right on the cardboard.
Make sure and trace the position of the gnomon on the asphalt so that
you can place it in the correct location and orientation on subsequent
days of observation. If students are using the straws they should
mark the cardboard, using a compass, to indicate north.
Position the gnomon in an open, sunny location. Every five minutes
have students mark the top of the shadow. They can also record the
time. Each period could do this in the same spot and by the end of
the day you would have a day’s worth of records. SAFETY NOTE:
Caution students never to look directly at the Sun.
After the shadows
are recorded, have students observe the pattern and make some observations
about what this tells us about the Sun’s apparent motion. Reinforce
the idea that the Earth is actually moving, not the Sun although the
Mayans, like all ancient peoples, thought the Earth stood still.
Remove the
gnomon and use the center of its position as the center of a circle.
Use string to draw a circle that will go through the shadows. Find
the shortest shadow and note the time. The shadow at solar noon should
be the shortest. If it is winter, this shadow is pointing north. If
it is summer, the shadow is pointing south. Label this point on the
shadow north and draw a straight line from it through the center of
the circle to the opposite side of the circle and label that point
South. To mark East and West, connect the end points of equal length
shadows.
Discussion Questions:
1. Why is the shortest shadow at noon?
2. Why is it pointing north?
3. Why do the long shadows start in the West and end in the East,
if the Sun rises in the East?
4. What does this motion tell us about the rotation of the Earth on
its axis?
5. How would the Mayans use this information to help them grow crops,
lay out their fields, orient their temples and houses?
Students should record all observations, reflections, conclusions
and questions in their journals.
Note: The observations using the gnomon can be repeated weekly. Students
can note changes in the position of the shadow and length of the shadow
at different times of the day as the year progresses. These types
of observations over a year’s time were used to chart seasonal
changes, predict solstices, and make calendars.
For more activities on developing the compass rose and finding the
azimuth of the Sun’s location see Astronomy with a Stick at http://www.nsta.org/320/.
Activity 2: The Analemma
Introduction:
The Analemma is the figure 8 path that the Sun traces on the
Earth’s surface as the Earth revolves around the Sun. The most
Northern point of the curve corresponds to the Summer solstice in
the Northern Hemisphere and the most Southern point corresponds to
the Winter solstice. The Mayans had a very sophisticated understanding
of the path of the Sun throughout the year. They built temples at
a distance from their observatories to serve as false horizons above
the forest so they could observe the Sun’s position on the horizon
daily. In addition, most Mayan cities were South of the 23 1/3 degrees
North latitude. Therefore, the sun would pass directly overhead twice
a year near the solstices. This event is called the Zenial passage
and can only be observed in the tropics. These days were associated
by the Mayans with a special god, called the Diving God. At the temple,
Chichen Itza, the spring and summer equinoxes cause a sun serpent
to rise up the side of the stairway called El Castillo. Temples in
Guatemala are built to align with the sun during the summer solstice,
the equinox and the winter solstice.
Materials:
•Small
foam balls (approximately 2 inches in diameter)
•colored
sticky dots
•
a bare light bulb in a light socket
•
an extension cord
•
a copy of the analemma for each student
•
cardboard or tag board the same size as the analemma
•
colored push pins or alternately colored pencils
•
glue sticks.
Procedure:
Part A: Modeling
Earth’s Rotation Around the Sun
1. Give each student a foam ball and have them place it on the top
of a pencil. Ask students to hold the ball vertically and draw an
approximate equator. Have the students mark or put a colored dot at
the location of the North Pole. Have them place another dot at approximately
the location of Los Angeles (34 degrees north of the equator).
2. Place
the light bulb and socket in the middle of the room, high enough so
that the light will reflect on the foam balls when the students are
standing. Have students form a wide circle around the bulb. Indicate
a location in the room that will serve as the North Star. This can
be a sign that you have posted or use the classroom clock or flag.
Have the students tilt their Earth modules so that the North Pole
is pointing to the North Star. Emphasize that students have to keep
their Earth modules in that orientation.
3. Turn
off the lights and have students walk slowly around the light bulb.
They are to observe the position of the brightest light on the Earth
as they move. The observations might be easier if they actually look
at the ball that is opposite them in the circle. What do they notice
about the light as the Earth revolves around the Sun? In what location
is it the brightest above the equator? Below the equator?
Discussion Questions:
Have students write about the model in their journal, what were we
observing.
1. Why was
the Earth pointed towards the North Star?
2. When the journey around the Sun was there summer in the Northern
Hemisphere? Winter?
3. Discuss the seasons and the apparent path of the Sun. Was the Sun
or Earth moving?
4. On Earth’s surface what appears to be moving?
Part B
Procedure:
1. Give students the Analemma. If using pushpins, have
them glue it onto cardboard or tag board.
2. Explain that this represents the apparent path of the Sun over
Earth’s surface. Have students identify the equator and the greatest
latitudes North and South.
3. Discuss Los Angeles’ location and have students figure out
when our days would be the longest based on the analemma. Identify
that date, June 21, as the summer solstice. Have students locate the
autumn solstice. Have students mark these dates with a push pin or
a colored pencil. Find the equinoxes by locating the time when the
Sun is directly over the equator. How many hours of daylight are there
on the equinox?
4. With a pin or colored pencil, mark the approximate location of
today’s date. Then have students mark their birthday. Will the
daylight hours be longer or shorter than today on their birthday.
Continue to let students find significant dates such as various holidays,
parents’ birthdays, etc. and analyze where they fall on the analemma
and the amount of daylight.
5. Relate various locations on the analemma with the seasons in our
local. What season is it when the sun is below the equator? Above
the equator?
6. Finally, if a Mayan village was located at 20 degrees North latitude.
What two days would the sun be directly overhead? How would the Mayan
astronomers know that the Sun was directly overhead? Share with students
the significance of these days in Mayan culture and astronomy.
Performance Task:
Have students reflect on their observations and the Sun’s apparent
motion. Ask them to contrast our modern understanding that the Earth
revolves around the Sun which is relatively fixed in its position
to the Mayan understanding that the Earth is fixed and the Sun is
moving. Have students reflect on the importance of knowing the patterns
of the Sun’s movement to the Mayans in particular to agriculture
and preparing for seasonal change.
Additional information about the analemma, including an interactive
site can be found at
http://www.analemma.com/Pages/framesPage.html and
http://www.analemma.com/SunGraph/index.html.
Activity 4: Moon Watching
Introduction:
The Mayans had a lunar component to their calendar. They made very
accurate observation and records of the moon and predicted eclipses.
Their predictions are recorded in the Dresden Codex.
Materials:
•
Foam balls (use the same ones as used for activity 3)
•
a light socket and bulb
•
extension cord
Procedure:
Part A: Long term moon watching
Students will get many benefits from directly observing the moon every
night or day for a month. After the initial introduction, it is a
homework assignment. Choose a day to begin this assignment about a
month before teaching the unit. Choose a day when the Moon is visible
during the day (check the newspaper or watch the moon yourself). (SAFETY
NOTE: Caution students never to look directly at the Sun.)
Show students
how to locate the moon. Explain that the moon is visible at different
times of the day. Their assignment is to locate the moon and to sketch
its appearance. Since the Moon’s position moves, they have to
note its appearance relative to a location on Earth. Show students
how to select a fixed point such as a tree or building. Have them
use their fists to measure how many fists above that point the Moon
is. Make their first recording.
Students
are then assigned to record the position of the Moon and its shape
every day or night for a month. The drawing should always include
their fixed point and the Moon’s relationship to it. Note: The
times of the Moon’s rising and setting are printed in the newspaper,
along with the phase that the Moon is in. You may want to tell students
where to get this information or you may not want them to know until
they have done some observations on their own. Alternately, you can
post the times for the students without the accompanying picture.
Part B: Moon watching in the classroom
Procedure:
1. First review the terms revolution and rotation
with a short simulation. Have a student stand in front of the room
facing the back wall. Have them turn, rotate, counterclockwise. The
student will face the back wall, then the left wall, then the front
wall, then the right wall. Define this movement as a rotation. Then
have two students come to the front. One is the Earth and the other
the Moon. In this simulation the Earth stays stationary and the Moon
moves. The Earth faces the back of the room. The Moon stands behind
the Earth also facing the back of the room. The Moon moves around
the Earth. This motion is revolution. Now repeat, the movement, but
this time the second student faces the Earth and always stays facing
the Earth. In the second simulation, the Moon revolves and rotates
once just like the actual Moon’s motion about Earth.
2. If students have done the month long observations of the moon,
have them create a class chart of the position and shape of the moon.
Discuss their observations thoroughly before doing the simulation.
Hand out the foam balls, place the light in the middle of the room
and have the students face the light holding their Moons toward the
light. Tell students that the balls now represent the Moon and their
heads are the Earth. Students should hold the ball in front of them
facing the light. Can they see the light face of the ball? Now have
them slowly move the ball around their head in a counterclockwise
motion. They should note when they can see a lit section of the ball
and what it looks like. Have them complete the revolution several
times slowly and help them identify the Moon phases. What is the position
of the Earth, Moon and Sun when there is a full moon? When there is
a new moon? When there is a quarter moon? Where does the light of
the moon come from?
Discussion:
Have students enter their observations in their journals along with
pictures and diagrams. Discuss how this information would be useful
to ancient civilizations.
1. What
would be beneficial about being able to predict eclipses?
2. Why were Moon phases important to the Mayans? Extension: Have students
draw a rabbit on the moon as the Meso-Americans did.
Many views of the Moon, Earth and Sun can be found at
http://www.fourmilab.ch/earthview/vplanet.html.
(This activity is adapted from the GEMS guide, Earth,
Moon and Stars by Cary I. Sneider.)
Activity 5: Tracing the Ecliptic
Introduction:
Earth revolves around the Sun along a two dimensional path called
the ecliptic. Therefore, the Sun appears in front of a fixed
order of constellations in the night sky. These constellations were
identified and named by the Babylonians and later by the Greeks. The
Babylonians called these 12 constellations the Zodiac. The Mayans
also identified the ecliptic and it was pictured as a double-headed
serpent. The Mayans identified their own patterns and names with the
stars in these constellations. They have a scorpion and to the Mayans,
what the Greeks called Gemini they identified as a pig. They also
have ecliptic constellations identified as a jaguar, a serpent, a
bat, a turtle and shark or sea monster.
Materials:
•A
large area for the simulation
•Names
of the Zodiac constellations or pictures of the constellations on
posters
•Sun
and Earth posters.
Data
Table for the Zodiac Constellations:
Procedure:
1. Share the information about the ecliptic and its
importance to the Mayans.
2. Move to an open area to do the simulation.
3. Choose one student to be the Sun and one to be the Earth. Choose
twelve students to form the Zodiac. Each student will hold one of
the signs. Have the 12 students form a large circle with the Sun in
the center. The student playing Earth should move in a counterclockwise
movement and should begin with Pisces behind the Sun. The student
playing Earth revolves around the Sun and states what constellations
s/he sees partially covered by the Sun. Have students change roles
and do the simulation a few times.
Discussion:
Students should record their observations. Make sure they record what
was moving. 1. Did the constellations move?
2. Did the Sun move? Discuss the relative size of the Sun to the stars
in the constellations. The ancient Mayans thought the Earth stood
still. Therefore what appeared to be moving to them?
3. The Babylonians used the Zodiac to predict human events. What could
be the importance of the ecliptic constellations to the Mayans?
Extension:
Have students research their Zodiac constellation and make a poster
explanation the constellation and its significance historically.
This activity
was adapted from Project ASTRO Resource Notebook from the Astronomical
Society of the Pacific.
More information
on the ecliptic can be found at Zodiac Constellations: Explanations
of the Greek legends, pictures of the constellations.
http://homepage.mac.com/kvmagruder/bcp/zodiacal/zoo.htm
Astrology: Contains star maps of the zodiac constellations in the
night sky
http://www.dacha.freeuk.com/zodiac/
The constellations
of the Zodiac are along the orange dotted line. Note the order.
The
Analemma Curve
Web Sites and Other Resources:
Me
and My Shadow: Making the Earth Sun Connection
http://www.wsanford.com/~wsanford/exo/sundials/shadows.html
The Analemma:
Advanced explanation, including videos and math equations that calculate
real sun location as opposed to mean sun location based on tilt of
the earth’s axis. Also links to a downloadable analemma that
students can manipulate to find sun’s location on various dates.
http://www.analemma.com/Pages/framesPage.html
Cyber sleuth Kids:
Ancient Civilizations: Student friendly web site with good information
about Mayan civilization
http://cybersleuth-kids.com/sleuth/History/Ancient_Civilizations/Mayans/
Zodiac Constellations:
Explanations of the Greek legends, pictures of the constellations.
http://homepage.mac.com/kvmagruder/bcp/zodiacal/zoo.htm
Astrology: Contains
star maps of the zodiac constellations in the night sky
http://www.dacha.freeuk.com/zodiac/
Mesoamerica: Pictures
and articles
http://www.jqjacobs.net/mesoamerica/index.html
Archaeoastronomy:
Relates Earth’s movement around the sun to solstice, equinox,
etc.
http://www.archaeoastronomy.com/
Ancient Astronomy
Web Site with interactive map
http://www.astronomy.pomona.edu/archeo/index.html
Archaeoastronomy
Index: Excellent articles by teachers on history of ancient civilizations
astronomy as well as related lessons
http://www.unm.edu/%7Eabqteach/ArcheoCUs/index.htm
Mayan Culture:
Good brief descriptions of the importance of various astronomical
observations for Mayan cosmology.
http://www.michielb.nl/maya/
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