Download Investigation 1 Solar Nebula Theory Student Guide 3_16_13_draft

INVESTIGATION #1: BIRTH OF STARS AND PLANETS
INVESTIGATING THE SOLAR NEBULA THEORY
Scientists believe that some 13.7 billion years ago all
matter, energy and our universe itself was formed
from of a huge sudden expansion now known in
theory as the “Big Bang”. The matter created from this
genesis eventually cooled off, condensed and formed
the most basic building blocks of matter known as the
elements. In space these elements are found in huge
clouds of gas, dust and ice called nebulae. For
centuries, astronomers have believed that planets
and stars form from these nebulae. This idea was
called the “solar nebula theory.” Since 1990, a variety
of new telescopes in space and on the ground have provided a great deal of
visual evidence which has supported the basic idea of the solar nebula theory.
Using recent technologies, scientists are now able to capture high resolution
images within nebulae that reveal distant solar systems in various stages of
formation.
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What caused our sun and solar system to form?
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What are the stages of solar system development?
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What evidence supports the Solar Nebula Theory?
GOALS:
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In this investigation, you will …
Use photographs showing various distance scales to develop an
understanding of the process of solar system formation.
Recognize that gravity is the driving force behind solar system formation.
Recognize that the matter and the elements that make up a nebula are
conserved during the formation of a solar system.
Recognize that density of the elements plays a role in the arrangement of
the formation of a solar system.
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INVESTIGATION OVERVIEW:
A synopsis of this lesson is as follows…
In this investigation, we will examine Hubble telescope photographs of the
Orion Nebula in various stages of condensation. The Orion Nebula is
approximately 1500 light years away from Earth and provides scientists with a
view that is relatively close compared to other observable nebulae. Using these
detailed photographs we can develop an understanding of the progression a
nebula takes from being a cloud of gas and dust to a star and its system of
orbiting planets. We will examine the role that careful visual observations of the
Orion Nebula have played in our understanding of solar system formation. The
development of new technology allows for more and more data to be gathered
and also for more precise analysis of that data. This allows scientists to improve
their models and explanations hence giving further support to the solar nebula
theory.
CONNECTIONS AND CROSS CUTTING CONCEPTS
Scientific Content  Gravity is a pulling force that acts over extremely great distances.
 Gravity pulls particles of nebular dust together to form stars and planets.
 The process of star and solar system formation is overwhelmingly long.
 Observing, inferring, and communicating scientific information.
 As the technology for observation improves, so does our knowledge of
astronomy.
Energy and Matter  The same elements found in a nebula are the same elements found in a
solar system from which it was made. - Law of Conservation of Matter
Scale Proportion and Quantity –
 Distance Scaling
 Dimensional Analysis
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Let’s Investigate … How does gravity make stars and planets?
Part A:
Within the Milky Way Galaxy, towards one of the outer edges, is a
relatively small star, our Sun. If we were to focus more closely around the parts
of the galaxy near our Sun, we see evidence of eight planets that are in orbit
around the Sun. These planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Uranus and Neptune), with the Sun, comprise our solar system. (see D in the
following picture).
In the solar nebular theory, astronomers, scientists that study the stars,
planets and universe, describe how the force of gravity makes immense clouds
of dust and gas condense, or become smaller (A in the picture below). As these
clouds under the continuing forces of gravity, become smaller and smaller, they
flatten into slowly spinning disks (B in the picture below). Most of the mass in
these disks ends up in the center of the disk, forming a dense blob of matter that
eventually becomes a star (C in the picture below). Some of the matter in these
disks condenses to form planets, which then orbit the star. An example of this is
our solar system shown in D in the picture below.
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In the 8th grade, you learned a lot about the gravity. In the Planetary
Systems unit, a video showed you how gravity keeps planets in orbit and acts on
stars and planets. You whirled a ball around your head to see how gravity kept
the moon in orbit around the earth, and keeps planets in orbit around the sun.
Some activities showed you how the force of gravity has different strengths on
different planets.
It certainly makes sense that gravity could act as described in the paragraphs
above in order to make stars and planets. But scientists are not satisfied with
speculation that this simply seems to make sense. Astronomers want to see
more direct visual evidence that the ideas outlined above are actually occurring.
Shown in the following sequence of images are examples various stages in the
development of stars and planetary systems within the Orion Nebula. These
images have come from the Hubble Telescope that has been collecting data on
our universe for the past 20 years.
This is the type of data that
astronomers use as evidence
supporting the solar nebular
theory. Your teacher will help you
to identify some of the features
shown in these images.
Shown here in Image 1 is the
Orion Nebula in its entirety. The
Orion Nebula stretches 24 light
years across. Light-years are a
unit of measurement that
astronomers use to describe
distance in the universe. A lightyear is the distance that light can
travel in one year. Recall from
your 8th grade unit on the
transformation of energy that light
travels at 300,000,000 (or 3x108)
meters per second. There are
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Image 1
86,400 seconds per day (60 seconds per minute x 60 minutes per hour x 24
hours per day) and 31,536,000 seconds per year (86,400 seconds per day x 365
days per year). That means that in one year light travels about
9,460,800,000,000,000 meters (about 5,900,000,000,000 (or almost 6 trillion
miles)!
Image 2 (below) is taken from a smaller, more condensed section located near
the center of the Orion Nebula.
Image 2
The image directly below is
taken from an even smaller
section from the image at
left and only shows about
.4 light years from left to
right.
Image 3
.4 Light Years
0.14 Light Years
12.8 Light Years
Image 3: This picture is 0.14 light years across. It would fit in the tiny box shown
inside Image 2. Five stars are in the process of being born in this part of the
Orion Nebula. The largest object in Image 3 shows a blob of luminous gas
surrounding the object that is becoming a star.
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Journal Reflection: Within Image 3 there is evidence suggesting the formation
of stars. With help from your teacher, describe in your journal what this evidence
might be. Be sure to justify why you think your evidence suggests the formation
of stars.
Below: Images 1, 2 and 3 of the Orion Nebula to scale.
Image 3 is indicated by a small black square inside of Image 2
Image 1
Image 2
■
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Answer the following questions in your journal:
Question #1: Does gravity act to cause nebula to grow larger by expanding, or
to grow smaller by contracting? Provide evidence to support your answer.
Question #2: If gravity does influence the nebula, then which of the three
images, 1,2 or 3 best represents the earlier stage of formation for stars and
planets? Justify your answer.
Question #3: If gravity continues to act upon the nebula, what do you predict will
happen to the gas clouds? Justify your answer.
Applying what you have learned …
The following three images are of other nebulae that are in different stages of
solar system formation. After reading the descriptions of each image apply what
you have learned about the effect that the force of gravity plays in the formation
of stars and solar systems to determine which of these images should come first
(earliest), which second, and which last (latest) in a sequence of star/solar
system formation
.
Image 3 – The dark cloud in the center of this image contains a lot of dust. It is
visible as a dark spot because it is in front of a gas cloud which is being lit up by
a star. This dark cloud of dust is about one light-year (6 trillion miles) across.
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Image 4 – This image is 2.5 light years (about 15 trillion miles) across. The light
colored areas are gas, re-emitting light from stars, some of which you can see in
the picture. The dark colored areas are dust.
Image 5 – A Hubble Space Telescope picture of a ring of dust around the bright
star Fomalhaut, located in the constellation of the Southern Fish. Fomalhaut is
visible as a faint, whitish dot in the center of the picture. This ring of dust is 0.002
light years (approximately 2 billion miles) across. As a comparison with the
distance that this dust ring is from Fomalhaut, Pluto’s orbital distance from the
Sun would be about 7 billion miles.
Question #5: Which of the images shows a star/solar system in the earliest
stages of formation? Justify your answer.
Question #6: Which of the images shows a star/solar system in the latest stages
of formation? Justify your answer.
Journal Reflection: Based on your answers to the above questions, describe in
your journal how astronomers can use evidence from the Hubble Telescope to
determine how stars and solar systems form.
Summary of Investigation …
In your journal, write a concise summary of this investigation. Be sure to
address the following questions and use your data to support your responses.
 What force is responsible for the formation of stars and planets from
interstellar gas?
 Describe the process in which a star system is created.
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Investigating Further …
Using your textbook, notes and the World Wide Web, gather information
before answering the following questions. Be sure to cite your sources.
ELEMENTAL MATTERS
1. The Law of Conservation of Matter states that all matter can be changed
into different forms but cannot be destroyed or created. How does the
solar nebula theory follow the law of conservation of matter? What
elements are present in the nebula / solar system before and after the
formation of a solar system. Provide evidence to support your answer.
2. How do the atomic masses / densities of the elements within the nebula
contribute to the layout of the solar system itself ? (Order of planets, Star
Location, Orbits, etc) Provide evidence to support your answer.
3. Scientists have recently discovered “blue bullets” within the Orion Nebula.
As you read the following article complete your RARE graphic organizer
as you think about the following:
A. What elements are present within the nebula?
B. What is creating the blue bullets?
C. Describe the advancements in telescope technology that made this
observation possible?
Click Picture
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