Download 30galaxies and the universe

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30 GALAXIES AND THE UNIVERSE 165 points
SECTION 30.1 The Milky Way Galaxy
In your textbook, read about discovering the Milky Way. (20 points)
For each item in Column A, write the letter of the matching item in Column B.
Column
Column B
A
a. Cepheid variables
______ 1. Stars in the giant branch of the H-R diagram
b. luminosity
that pulsate in brightness because of the expansion
c. RR Lyrae variables
and contraction of their layers
______ 2. Stars that have periods of pulsations between 1.5 d. Sagittarius
e. variable stars
hours and 1.2 days, and on average, have the same
luminosity
______ 3.
______ 4.
Stars with pulsation periods between 1 day and more than 100 days
By measuring a star’s period of pulsation, astronomers can determine
this
Date
Period
In your textbook, read about the mass of the Milky Way.
Use each of the terms below just once to complete the passage.
2.6 million
stellar remnants
100 billion
halo
dark matter
supermassive black hole
galaxy
The mass located within the circle of the Sun’s orbit through the
galaxy is about (12) ______________________ times the
mass of the Sun. Because the Sun is of average mass, astronomers
have concluded there are about 100 billion stars within the disk of
the (13) ______________________.
Astronomers have found evidence that much more mass exists in
the outer galaxy. Evidence indicates that as much as 90 percent of
the galaxy’s mass is contained in the (14) ____________ .
This mass is not observed in the form of normal stars, and
astronomers hypothesize that some of this unseen matter is in the
______ 5.
form of dim (15) ______________________ , such as
white dwarfs, neutron stars, and black holes. The remainder of this
In your textbook, read about the shape of the Milky Way.
For each statement below, write correct or not correct. If the statement is not correct, use
proofreading marks to make it correct.
mass, usually called (16) ______________________ , is a
mystery.
Studies of the motion of stars that orbit close to Sagittarius A
Direction of the center of the Milky Way is toward
this constellation
___________ 6.
indicate that this area has about (17) _________________
times the mass of the Sun, but is smaller than our solar system.
Astronomers believe that Sagittarius A is a (18)
___________ 7.
______________________ that glows brightly because of
Radio waves are used to map the Milky Way because they
can penetrate the interstellar gas and dust without being scattered
or absorbed.
Measurements of star luminosity at different distances
provide a hint of the Milky Way’s spiral arms.
the hot gas surrounding it and spiraling into it.
___________ 8.
Around the Milky Way’s nuclear bulge and disk is the halo,
where the globular clusters are located.
___________ 9.
Five major spiral arms and a few minor arms were identified
in the Milky Way..
__________ 10.
The Sun is located in the Milky Way’s minor arm Orion at a
distance of 26,000 ly from the galactic center.
__________ 11.
In its 5-billion-year life, the Sun has orbited the galaxy
approximately 100 times.
In your textbook, read about the formation and evolution of the Milky
Way and maintaining spiral arms.
19. What two theories explain how the spiral arms are
maintained?
What two theories explain how the spiral arms are maintained?
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Name_______________________________________________
SECTION 30.2 Other Galaxies in the Universe
In your textbook, read about discovering other galaxies. (8 points)
Circle the letter of the choice that best completes the statement or answers the question.
1. The question about other objects existing in the sky was answered by
Edwin Hubble in 1924. What did he discover in the Great Nebula in the
Andromeda constellation?
a. Cepheid variable stars
c. RR Lyrae variables
b. a supernova
d. a black hole
2. Disklike galaxies with spiral arms are divided into which of the
following two subclasses?
a. normal spirals and flat spirals
c. flat spirals and barred spirals
b. normal spirals and barred spirals d. loose spirals and flat spirals
3. Galaxies that are not flattened into disks and do not have spiral arms
are called
a. dwarf galaxies.
c. elliptical galaxies.
b. barred elliptical galaxies.
d. nebular galaxies.
4. Galaxies that do not fit into the spiral or elliptical classifications are
called
a. dwarf galaxies.
c. barred galaxies.
b. Hubble galaxies.
d. irregular galaxies.
In your textbook, read about the expanding universe, active galaxies, and quasars.
For each item, write the word from the box
_____________
5. Feature in the spectra
of galaxies that indicates that
they are moving away from
Earth
_____________
_____________
6.
_____________
Hubble constant
quasars
radio galaxies
redshift
About 70 km per second per megaparsec
7. Extremely bright galaxies that are often
giant elliptical galaxies emitting as much or more
energy in radio wavelengths than in wavelengths
of visible light
Date
Period
SECTION 28.1 Solar System Overview
25 points
In your textbook, read about collapsing interstellar clouds and Sun and planet
formation.
For each item, write the word from the box
inner planets
hydrogen
planetesimals
gravity
interstellar cloud
Jupiter
_____________
1. Gas and dust from which stars
and planets form
_____________
2. Force that pulls matter together
_____________
3. Solid bodies hundreds of
kilometers in diameter that
merged to form the planets
_____________
4. Believed to be the first large planet to develop
_____________
5. Main element in early interstellar clouds
_____________
6. Lacking in satellites because of proximity to the
Sun
Sequence the events of a collapsing interstellar cloud.
_____ The cloud becomes denser at the center.
_____ Rotation slows and the cloud flattens
_____ The cloud spins faster and faster.
_____ The cloud becomes a rotating disk.
_____ The collapse of the cloud begins to accelerate.
Describe the nebular theory of solar system formation and the
evidence supporting it. (6 points)
8. Starlike objects with emission lines in their
spectra
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SECTION 30.3 Cosmology (30 points)
In your textbook, read about models of the universe.
Use each of the terms below just once to complete the passage.
open
closed
The study of the universe, including its current nature, its origin,
2.725 K
compressed
and its evolution is called (1)
. The fact
cosmology
background noise
that the universe is (2)
implies
radiation
that it had a beginning. The theory that the universe began as a
density
point and has been expanding ever since is called the
Big Bang
lower
(3)
theory. The (4)
expanding
Wilkinson Microwave Anistropy Probe
of the universe determines the outcome
cosmic background radiation
of the Big Bang. In a(n) (5)
Date
Period
In your textbook, read about the Big Bang model.
Answers each question.
14. Name the three possible outcomes for the universe.
__________
_____________
___________
15. Describe the premise of the rate of expansion that these three possible
outcomes for the universe are based on?
16. Evidence suggests that the universe contains a great amount of
________________
17. The universe began as a point and has been expanding ever since is
called the
________________
____________
universe the expansion will never stop. In a(n) (6)
universe the expansion stops and becomes a contraction.
18. When the rate of expansion of the universe is known, it is possible to
calculate the
According to the more accepted theory, the Big Bang Theory, if the
________________
universe began in a highly (7)
state, it would
have been very hot, and the high temperatures would have filled it with (8)
________________. As the universe expanded and cooled, the
radiation would have been shifted to (9) ___________ energies and
longer wavelengths. In 1965, scientists discovered a persistent (10)
________________ in their radio antenna. The noise was caused
by weak radiation called the (11) ____________ It appeared to
19. Based on the best value for H that has been calculated, the age of the
universe is hypothesized to be about
20. Illustrate a star moving away from you and another star moving
toward you. Show how waves are shortened and elongated.
Label redshift and blueshift.
come from all directions in space and corresponded to an emitting object
___________
having a temperature of about (12)
, which is close to
the temperature predicted by the Big Bang theory. An orbiting observatory
________________, launched
called the (13)
the radiation in detail.
in 2001, mapped
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GALAXIES AND THE UNIVERSE
Reviewing Vocabulary
(35 points)
For each item in Column A, write the letter of the matching item in Column B.
______
______
Understanding Main Ideas
In the space at the left, write correct if the statement is correct; if the statement is
not correct, change the italicized word or phrase to make it correct.
1. The Milky Way is a spiral galaxy.
___________
3. Edwin Hubble measured the redshifts and
distances of many galaxies and found that the
redshift of a galaxy depends on its distance from
Earth.
___________
4. Cosmic background radiation provides
information about conditions now in the expansion
of the universe.
___________
5. One way to estimate the fate of the universe is to
measure how much acceleration has occurred in its
expansion.
___________
7. Persistent noise discovered in 1965 that is caused
by weak radiation from all directions in space
6. A key goal of the Fermilab is to gather data that
would help to pinpoint the value for H, the Hubble
constant.
___________
8. Model that says the universe will stop expanding and
begin to contract
7. Heavy elements found on Earth are formed in
stars.
___________
8. Our sun produces Helium by fusion of Lithium
atoms.
____________________
Column B
1. Study of the universe
a.
b.
c.
d.
3. Gigantic formation of
clusters of galaxies hundreds of e.
millions of light-years in size
f.
g.
4. A value of approximately
70 kilometers per second
h.
per megaparsec
2. Core of a galaxy in which
highly energetic objects or
activities are located
closed universe
cosmology
Big Bang theory
cosmic background radiation
open universe
Hubble constant
active galactic nucleus
superclusters
______
5. States that the universe began as a point and has been
expanding ever since
______
______
6. Proposes that the universe will never stop expanding
______
Period
___________
___________
Column A
______
______
Date
9. Describe the big bang theory and the two important pieces of
evidence that supports this theory.
___________
2. Studies provide evidence that there is a great
amount of unseen matter called dark matter
composed of dim stellar remnants that have no mass.
9. According to the redshift of spectral analysis
starlight, all of the galaxies are moving toward each
other.
___________
10. The fact that there are elements larger than Iron
on Earth provides evidence that a Supernova once
happened in this section of the Universe billions of
years ago.
___________
11. Radioactive decay suggests that the earth and
solar system are 4.6 billion years old.
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Name_______________________________________________
Date
Applying Scientific Methods
Period
Answer the following questions. (15
points)
1. What is a black hole?
2. In the chart, what unit of
measurement is used to show black hole
mass?
3. What do each of the three columns in
the chart show?
4. What is the mass of the largest black
hole on the chart?
What is the mass of the smallest?
5. According to the article, what did
astronomers once believe about black
holes?
Black Holes: One Size Does Not Fit All
Astronomers are concluding that monstrous black holes were not born that big, as once believed, but
instead grew on a diet of gas and stars controlled by their host galaxies in the beginning years of the universe.
An initial look at 30 galaxies indicates that black holes do not precede a galaxy’s birth, but instead evolve
with the galaxy by trapping an amazingly exact percentage (0.2) of the mass of the stars and gas in a galaxy.
Black holes in the centers of giant galaxies—some more than one billion solar masses—had enough
infalling gas to once blaze as quasars. The final mass of a black hole is not primordial, but instead is
determined during the galaxy formation process. This shows that there is a close relationship between the
black hole mass and the stars that comprise an elliptical galaxy or central bulge stars of a spiral galaxy. In
most cases, the black holes not only bulked up through the accretion of gas, but also through mergers of
galaxies in which pairs of black holes combined.
The Hubble Space Telescope precisely measures the speed of gas and stars around a black hole. This
measurement provides clues for the existence of a black hole. Astronomers determine the mass of each black
hole by measuring the motion of stars swirling around it. The closer a star is to the black hole, the faster is its
velocity.
6. What have astronomers learned from
the more than 30 black holes they now
study?
7. Other than accruing gas and stars,
how else can black holes increase in size?
8. How does the Hubble Space
Telescope measure black holes if black
holes cannot be seen?
Page 5
1. expansion of the universe
stops and begins to contract
back to original point of origin
2. when C is fused and energy
production ends expels outer
layers
3. Unknown component that makes
up about 23% of all matter in
the universe
4. expansion of the universe
slows to a halt, but never
contracts
6. star that is fusing H into He
9. stable final stage of a star
made of C
11. extremely dense final stage
of a star
17. used as evidence for the Big
Bang Theory
18. expansion of the universe
never stops
Down
Created by Puzzlemaker at
DiscoveryEducation.com
Big Bang Theory
Life Cycle of Stars
20 points
Date
12. cloud of interstellar gas
and dust which collapses on
itself as a result of gravity
13. end result of massive
star with so much pressure
pulling on gravity that light
cannot escape
14. star that has burned all
H into He and now begins
fusing He into larger
elements
15. theory that the universe
began as a point and has been
expanding ever since
16. hot condensed center
where fusion may begin
Across
5. study of the universe, its
nature, origin, and evolution
7. spinning neutron star that
pulsates a pattern of light
8. an explosion that blows away the
outer portion of a star fusing
together the heavier elements
9. probe launched by NASA to map
cosmic background radiation
10. massive star that fuses
elements up to Ni into layers
Across
Name_______________________________________________
Period
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