Download Chapter 5 Notes

Chapter 5 Notes/Section 1: Stars
A. Patterns of stars – ____________
1. Ancient cultures used _________ or
everyday items to name constellations
2. Modern astronomy studies
_____constellations
3. Some constellations are not ______ all
year because Earth revolves around the
Sun
Chapter 5 Notes/section 1: Stars
4. ________ __________ in the northern sky
appear to circle around Polaris and are visible
all year.
B. Star ___________
1. __________ ___________– measure of the
amount of light a star actually gives off.
2. ____________ ___________ – measure of
the amount of a star’s light received on Earth
Chapter 5 Notes/Section 1: Stars
C. Space _____________
1. Astronomers measure a star’s
_________ –shift in its position when
viewed from two different angles.
2. Distance is measured in ___________ –
the distance light travels in a year.
Chapter 5 Notes: Section
3/Evolution of Stars
A. Classifying stars – Ejnar Hertzsprung
and Henry Russell ___________ stars
by temperature and absolute magnitude
in a H-R diagram
1. _______ ___________- diagonal band
on H-R diagram
a. Upper left – hot, _______, bright stars
b. Lower right - ______, red, dim stars
Chapter 5 Notes: Section
3/Evolution of Stars
c. Middle – average _________ stars like
the Sun
2. __________ and ________ - the 10% of
stars that don’t fall in the main sequence
B. __________ of hydrogen occurs in star
cores releasing huge amounts of energy
Chapter 5 Notes: Section
3/Evolution of Stars
C. _____________ of stars
1. A __________ contracts and breaks apart from
the instability caused by gravity
a. ___________ in each nebula chunk increase
as particles move closer together
b. At 10 million K _________ begins and energy
from a new star radiates into space
Chapter 5 Notes: Section
3/Evolution of Stars
2. The new main sequence star _________
pressure from fusion heat with gravity
a. Balance is lost when core hydrogen fuel
is ________ ____.
b. Core contracts and heats up causing
outer layers to _______ and cool
c. Star becomes a _______ as it expands
and outer layers cool
Chapter 5 Notes: Section
3/Evolution of Stars
d. Helium nuclei fuse to form core of
_________
3. A ____________ _________ forms from
the giant star
a. Helium is exhausted and outer layers of
giant ________ into space
b. Core contracts into hot, dense, small star
Chapter 5 Notes: Section
3/Evolution of Stars
4. In massive stars fusion causes higher
temperatures and greater expansion into
a _________
a. Eventually fusion stops as iron is formed
b. The core crashes inward causing the
outer part to explode as an incredibly
bright ____________
Chapter 5 Notes: Section
3/Evolution of Stars
5. The collapsed core of a supernova may
form a __________ _______ of
extremely high density
6. A tremendously big supernova core can
collapse to a point with no volume
forming a __________ _________.
a. _____________ is so strong not even
light can escape
Chapter 5 Notes: Section
3/Evolution of Stars
b. Beyond a black hole’s _________
__________ gravity operates as it would
before the mass collapsed
7. Matter emitted by a star over its life time
is recycled and can become part of a new
__________
Chapter 5/Section 4: Galaxies of
the Universe
A. __________ gravity holds together a large
collection of stars, gas, and dust
1. Earth galaxy is Milky Way which is part of a
galaxy cluster named the ______ _____.
2. _______ _______ - spiral arms wind out from
inner section; some have barred spirals with
stars and gas in a central bar
3. _______ _________ - large, three-dimensional
ellipses; most common type
Chapter 5/Section 4: Galaxies of
the Universe
4. ________ ________- smaller, less
common galaxies with various different
shapes
B. The Milky Way Galaxy – usually
classified as a _______ ______ _____
1. Contains more than 200 ______ stars
2. About 100,000 light-years ______
3. Sun orbits galaxy’s core every 240
million years
Chapter 5/Section 4: Galaxies of
the Universe
C. Theories on the ______ of the universe
1. ________ ________ _________ universe has always existed just as it is
now
2. __________ _______ - universe
expands and contracts repeatedly over
time
Chapter 5/Section 4: Galaxies of
the Universe
D. Universe is __________
1. ________ ______ - light changes as it
moves toward or away from an object
a. Starlight moving toward Earth shifts to
_____ - ______ end of spectrum
b. Starlight moving away from Earth shifts
to ____ end of spectrum
Chapter 5/Section 4: Galaxies of
the Universe
2. All galaxies outside the Local Group
indicate a red shift in their spectra
indicating they are moving ______ from
Earth
E. ____ _______ _______ - holds that
universe began 12 to 15 million years ago
with a huge explosion that caused
expansion everywhere at the same time
Chapter 5/Section 4: Galaxies of
the Universe
1. Galaxies more than 10 ________ lightyears away give information about a
young universe
2. The universe may eventually _____
expanding and begin _________