AIDE
Earth Science Key Points
Chapter 5 "Stars and Galaxies"
Lesson 1 "Stars"
Key Vocabulary Terms
- fusion - process by which
particles combine to form a new particle.
- magnitude - brightness of
a star.
- apparent magnitude - how bright
a star looks
- absolute magnitude - how bright
a star actually is
Key Concepts
- Fussion is the process of
the hydrogen and helium particles in a star move at incredible speeds due
to the star's high temperature. The moving particles collide and fuse, producing
constant energy that makes the strs hot and glowing.
- A star's brightness is the
amount of energy it gives off and its distance from Earth.
- A star's apparent magnitude
is how bright it looks to an observer on earth. Its absolute magnitude is
how bright it really is.
- A star with a magnitude of
0 is brighter than a star with the magnitude of 1.
- A blue-white star is hotter
than a red star.
Did you learn these Objectives?
- Are you able to explain why
stars shine?
- Can you explain why some stars
are brighter than others?
- Are you able to determeine
a star's temperature by its color?
Investigation
5-1"Observing Brightness" (Optional, must complete 16 total investigations)
Key Concepts
- You will understand how distance
affects brightness and demonstrate the different brightnesses of stars.
Lesson 2 "Distances
to Stars"
Key Vocabulary Terms
- light-year - distance that
light travels in one year.
Key Concepts
- A light-year measures distance.
- Scientists use light-years
to measure distances to stars because if distances to stars were measured
in kilometers, the numbers would be very large and difficult to read and
work with.
- A light-year is trillions
of kilometers.
- Stars are much, much farther
apart than planets are. A spaceship going as fast as light could travel
between planets in minutes. If the spaceship traveled between stars, it
would take years.
- Astronomers measure how much
a nearer star's position seems to shift in relation to a more distant star
over a few months' time. They compare the absolute and apparent magnitudes
of two stars, knowing that if two stars have the same absolute magnitude,
the dimmer one is farther away.
Did you learn these Objectives?
- Are you able to define a light-year?
- Can you explain how far away
stars are?
Lesson 3 "The Life
of a Star"
Key Vocabulary Terms
- nebula - Cloud of gas and
dust in space
- red giant - star that has
expanded after using up its hydrogen
- supergiant - one of the largest
stars, formed when a star expands after using up its hydrogen; larger than
a red giant
- nova - brilliant explosion
of a red giant
- White dwarf - small, white,
hot, dense star that remains after a nova
- supernova - brilliant explosion
of a supergiant.
- neutron star - very small,
very dense star that remains after a supernova
- black hole - region in space
with tremendous gravity, caused by the collapse of a huge star
Key Concepts
- A star's life begins as a
swirling cloud of dust and gas is drawn together by gravity and, when it
gets hot enough, gives off energy from fusion.
- Gravity causes collapse, but
fusion causes heat and expansion.
- A supergiant is larger than
a red giant.
- A supergiant becomes a supernova
when gravity makes a supergiant collapse. Particles colliding in the center
of the star make it so hot that a huge explosion occurs, which is a supernova.
- When a star's life ends when
a small star swells into a red giant, expplodes as a nova, and leaves a
whie dwarf, which finally becomes a dead star. A large star becomes a supergiant,
explodes as a supernova, and leaves either a neutron star or a black hole.
Did you learn these Objectives?
- Can you describe how a star
forms?
- Are you able to describe the
life cycle of a star?
Lesson
4 "Groups of Stars"
Key Vocabulary Terms
- constellation - pattern of
stars seen from Earth
- galaxy - group of billions
of stars
- Milky Way Galaxy - group of
stars to which our solar system belongs
- universe - everything that
exists
Key Concepts
- A constellation is a pattern
of stars.
- Galaxies take on one of three
shapes: elliptical, spiral, or irregular.
- Our solar system is in the
Milky Way Galaxy
- When you look at the Milky
Way Galaxy you are veiwing the light from the distant stars of our galaxy
as it is viewd from the thin side, like looking at the edge of a plate.
- The Universe is made of all
the galaxies together; everything that exists.
Did you learn these Objectives?
- Can you explain what a constellation
is?
- Are you able to identify some
constellations?
- Are you able to identify the
galaxy that includes our solar system?
Investigation
5-2 "Making a Constellation Model" (Optional, must complete 16 total
investigations)
Key Concepts
- You will make a constellation
projection model.
Chapter Summary and Review
See pages 128-129
Chapter 5 Review answers are
1)
absolute magnitude.
2)
supergiant.
3)
white dwarf.
4)
light-years.
5)
supernova.
6)
constellations.
7)
galaxy.
8)
apparent magnitude.
9)
Milky Way galaxy.
10)
nebula.
11)
fusion.
12)
universe.
13A.
14.B
15.A
16.B
17.D
18.C
19.A
20.B
21)
D
22)
B