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Investigate Meteorites
amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
OverviewStudents will understand where meteorites come from,
what they are made of, and what they tell scientists about
planetary formation and Earths interior.
Before Your Visit: Students will read and discuss an
informational text on the clues that meteorites provide about
planetary formation and Earths interior.
During Your Visit: In the Arthur Ross Hall of Meteorites,
students will explore and take notes on meteorites in three
sections of the hall. Then, in the Gottesman Hall of Planet Earth,
students will sketch and gather evidence about what meteorites
reveal about planetary formation and Earths interior.
Back in the Classroom: Students will use what they learned from
the reading and notes from their visit to the Museum to produce an
illustrated text that defines meteorite; indicates where meteorites
come from; and presents evidence on how different types of
meteorites help us understand planetary formation and Earths
interior (core, mantle, and crust).
Background for EducatorsThe most important clues from the early
stages of the solar system come from meteorites. Some meteorites
are older than the formation of Earth. They reveal how smaller
bodies coalesced to form planets, and how our own planet developed
after it formed.
Before Your VisitActivity: Reading
In this activity, students will read and discuss an
informational text on the clues that meteorites provide about
planetary formation and Earths interior.
Have students read What Is a Meteorite? independently. Ask them
to use the large margin on the right-hand side of the page for note
taking as they read. For example, ask them to underline and star
key passages in the text and use the margin space to paraphrase the
information they think is the most important. They may also use the
space to draw diagrams of the processes they are reading about, or
to write down questions about part of the text they dont
understand.
Then use the prompts below to guide a class discussion:
What is a meteorite? (A meteorite is a rock that falls to Earth
from space and refers only to those bodies that survive the trip
through the atmosphere and reach Earths surface.)
How can studying meteorites from planets, the Moon, and some
large asteroids help scientists understand Earths interior? (As the
solar system formed, objects collided and stuck together, forming
larger and larger bodies such as asteroids, planets, and the Moon.
All of these partially or completely melted, and layers sepa-rated
out. Dense, metallic materials sank to the center to form the core,
while lighter materials formed the mantle. Further melting formed
the rocky crust. This process is called differentiation. Study of
meteorites from these differentiated bodies can help us to
understand Earths interior since it too went through this
process.)
What is an iron meteorite? What does studying this type of
meteorite tell scientists about Earths core? (Iron meteorites are
shattered fragments of the metal cores of differentiated asteroids
or proto-planets. Scientists know from studying these meteorites
that Earth has a center, or core, made of nickel and iron metal and
that other planets have metal cores as well.)
NYS Science Core CurriculumPS 1.1c: The Sun and the planets that
revolve around it are the major bodies in the solar system. Other
members include comets, moons, and asteroids.
Plan how your students will explore the Arthur Ross Hall of
Meteorites using the student worksheets.
Distribute copies of the worksheets to students before coming to
the Museum. You may want to review the worksheets with them to make
sure they understand what they are to do.
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amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
What are the two types of stony meterorites? What do they tell
us about the solar system and Earth? (Unmelted stony meteorites
called chondrites tell us about the early solar system because they
have remain unchanged. Partially melted stony meteorites, called
achondrites, show that when planets and asteroids melted, they
separated into metal and stony parts.)
What are stony-iron meteorites made of? What do some scientists
theorize that pallasites show about Earths formation? (Stony-iron
meteorites are a mixture of metal and rock. Some scientists
theorize that pallasites are samples of the boundary between the
metal core and the olivine-rich mantle around it.)
What are some things that the study of meteorites has helped
scientists understand our solar system? (They provide evidence for
the beginnings of our solar system, how planets and asteroids
formed, and how impacts of large meteorites have altered Earths
history and life on our planet.)
Activity: Explore Density
In this activity, students will investigate why some materials
sink to the core of a planet while others float to the crust. This
experiment uses marshmallow fluff and molasses to illustrate the
concept of planet differentiation.sHave students determine the
density of marshmallow fluff and molasses by filling identical
beakers to the same level with each material and weighing both
beakers. Then, place a dome of marshmallow fluff in the bottom of a
clear bowl. Have students thin out fluff near edges and add
molasses until it is about 3 deep. Ask students to predict what
will happen and why. Then, observe what happens. Which material
ends up on top? Why? Discuss the results with students and have
them draw conclusions about why dense material is at the core of
differentiated planets.
During Your Visit Arthur Ross Hall of Meteorites 1st floor
(30-40 minutes)
In the Building Planets section of the hall, students will use
the worksheet to sketch and gather evidence about what meteorites
reveal about planetary formation and Earths interior.
Gottesman Hall of Planet Earth 1st floor (30 minutes)
Students will explore various sections of the hall to gather
additional evidence about how scientists understand Earths
interior:
In the How Earth Formed section, have students explore the
density blocks and diagrams to understand more about how Earths
layers are organized.
In the Earthquakes section, have students examine what seismic
waves tell us about the make-up of Earths interior.
In the Volcanism sections, have students watch videos of
scientists visiting lava flows to explore how lava flows help
scientists understand the make-up of Earths interior.
Back in the ClassroomActivity: Write an Illustrated Text
Using what theyve learned from the pre-visit reading and their
Museum visit, have students create an illustrated text that:
defines meteorite indicates where meteorites come from presents
evidence on how different types of meteorites help us understand
planetary formation and Earths
interior (core, mantle, and crust)
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Student Reading
amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
Meteorites: Clues to Planetary Formation
What is a meteorite?
In simplest terms, a meteorite is a rock that falls to Earth
from space. The word meteorite refers only to those rocks that
survive the trip through the atmosphere and reach Earths
surface.
Meteorites are rocks, but not like Earth rocks. Most meteorites
are far older. They provide some of the only samples we have of
other objects planets, asteroids, and possibly comets in our solar
system. Some meteorites even contain tiny particles that formed
around other stars that existed before our Sun. Studying meteorites
helps us understand how the solar system and the bodies in it
formed.
Where do meteorites come from?
Our solar system began to take shape some 4.6 billion years ago.
At that time, the Sun and planets as we know them now did not
exist. Back then a large cloud of gas and dust known as the solar
nebula swirled around the developing Sun.
As the solar system formed within this swirling cloud, countless
small objects collided and stuck together. Gradually, they formed
larger and larger bodies such as asteroids and planets.
An artists rendering of the early solar system.Photo William K.
Hartmann
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amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
Some meteorites are pieces of planets, the Moon, and some large
asteroids that show evidence of partial or complete melting within
those bodies. This melting was the result of intense heat and
pressure that occurred as the objects accreted. Accretion is when
materials come together under the influence of gravity to form a
planet, moon, asteroid, or comet. When the materials came together
and the body increased in size, the heat and pressure increased.
This caused melting. As this melting occurred, layers separated out
in a process called differentiation. Dense metallic materials sank
to the center where it crystallized to form the core. Less dense
materials formed the mantle. Further melting formed the outer rocky
crust. Meteorites from these differentiated bodies are rare finds
but very valuable because they help us understand how planets
formed and what their deep interiors are made of. What does
studying different types of meteorites tell us?
Meteorites are all rocks from space. But they are not all alike.
There are three main groups: iron meteorites, stony meteorites, and
stony-iron meteorites. Each group of meteorites is split into many
more classes and types. The class or type depends upon the minerals
they contain, their chemistry and their structure. The different
types provide us with information about a range of processes that
occurred earlier in our solar systems history.
1. Stony Meteorites
The most common meteorites are stones. They could easily be
mistaken for ordinary rocks from Earth. Stony meteorites fall into
two main groups. Chondrites the more common type, are the oldest
rocks formed in our solar system. These ancient stones offer a
record of the solar system in its infancy. Since many have not
changed, scientists use the age of these rocks to determine the age
of our solar system. They are clues to what conditions were like
when the solar system was young. They also give us hints about the
elements that exist in our solar system.
Achondrites are pieces of planetary bodies that partially melted
while they were in space, as described above. Studying these
meteorites teaches us about the history of melting planetary bodies
like Earth, the Moon, and the other rocky planets and moons.
Meteorites: Clues to Planetary Formation page 2
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amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
2. Iron Meteorites
The meteorites known as irons are more than 98 percent metal.
Almost every iron meteorite comes from the iron core of an asteroid
or planetary bodies. As described above, the iron core formed when
the asteroid differentiated. Study-ing these meteorites is one of
the ways that scientists know that Earth has a core made of nickel
and iron metal. The other planets have metal cores as well.
3. Stony-Iron Meteorites
Stony-iron meteorites are a mixture of metal and rock. There are
two different kinds: mesosideroites and pallasites. The Stony-Iron
meteorites called mesosiderites form when asteroids collide. In the
crash, the molten metals and solid pieces of sili-cate rocks of
both asteroids get mixed. Because of that, mesosiderites may record
the history of both meteorites.
Other stony-iron meteorites are called pallasites. Pallasites
contain green crystals of the mineral olivine that are surrounded
by metal. These meteorites are extremely rare. They make up less
than one percent of all known meteorites. Some scientists think
that they resemble the material that makes up the boundary between
Earths core (made of metal) and mantle (made mostly of
olivine).
Meteorites: Clues to Planetary Formation page 3
Photo AMNH/D.Finnin
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Go to the Building Planets section of the hall.
1. In the Crust exhibit, select a meteorite. Sketch and label
it. What is the common rock type in these
meteorites?
Why did the rocky material rise to the surface
when the planets formed?
2. In the Mantle exhibit, select a meteorite. Sketch and label
it.
What are these Stony-Iron Pallasite meteorites made of?
Where do they come from?
3. In the Core exhibit, select a meteorite. Sketch and label
it.
What are these meteorites made of?
Where do they come from?
Student Worksheet
amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
-
Go to the Building Planets section of the hall.
1. In the Crust exhibit, select a meteorite. Sketch and label
it. What is the common rock type in these
meteorites?
(basalt) Why did the rocky material rise to the surface
when the planets formed?
(It rose because it was less dense.)
2. In the Mantle exhibit, select a meteorite. Sketch and label
it.
What are these Stony-Iron Pallasite meteorites made of?
(iron mixed with Olivine crystals)
Where do they come from?
(These meteorites come from the region between the crust and the
core of a differentiated asteroid.)
3. In the Core exhibit, select a meteorite. Sketch and label
it.
What are these meteorites made of?
(iron) Where do they come from?
(These meteorites come from shattered fragments of the metal
cores of differentiated asteroids.)
Student Worksheet
amnh.org/meteorites
ARTHUR ROSS HALL OF METEORITES Grades 6-8
2013 American Museum of Natural History. All rights
reserved.
Answer Key