Download Dim Stars - granthamkuehl

In our study of
Stars
The students will be able to
Determine color, temp., brightness
and Size of a star
And show what they learned by
Interpreting the HR Diagram
WARM-UP
Scientists classify stars based on their
brightness (Luminosity)
And
Temperature
Classifying Stars
• Astronomers classify
stars according to:
•
•
•
•
size/mass,
temperature,
color, and
brightness.
• How bright a star or galaxy shines is its
brightness or luminosity
Luminosity (Brightness)
Draw this graph in your
journal:
Temperature
Now add your numbers
Along the edge of the
graph
Notice what happens to the numbers as we move from Left to Right.
Now add your numbers
Along the edge of the
graph
Increasing Temperature
Now add your numbers
Along the edge of the
graph
Hotter
Colder
Bright
Stars
Increasing
Luminosity (Brightness)
Now let’s look at
Luminosity:
Dim
Stars
Temperature
Now let’s begin placing our different types of stars
White Dwarfs
(Dead Stars
Now let’s begin placing our different types of stars
Main Sequence Stars
(Very stable in their life,
Young to middle aged
stars)
White Dwarfs
(Dim Stars)
White Dwarfs
(Dim Stars)
Our Sun
White Dwarfs
(Dim Stars)
Star Temperatures
Color of a star
indicates its surface
temperature
Red stars are the
”coolest” while blue
are the hottest
Sun is a yellow star
Hertzsprung-Russell Diagram
17
27.2 The size of
stars
•
•
•
Stars come in a range
of sizes and masses.
Our Sun is a mediumsized star.
The largest stars, giant
stars have a mass of
about 60 times the
mass of the Sun.
• Which star is hottest supergiant?
• What temperature is Sirius B?
Which star is the dimmest (least bright) on the chart?
Order these stars from hottest to coolest:
Procyon, Spica, Sirius B, and Pollux