Download Answers Universe Cornell Notes Chapter 8, Sec 2

Topic: Chapter 8, Sec 2:
Characteristics of Stars
Name:
Date:
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Class: Science 8 GT
If we could travel at the
speed of light, how long
would it take to get to our
sun?
What about Proxima
Centauri, our next nearest
star?
What is a light-year?
It would take you 8 minutes, 20 seconds to travel to the Sun.
What is it used for?
To measure the distances to stars.
With what unit do we
measure distances inside our
solar system?
What is Parallax?
We measure distances inside the solar system in AU
(Astronomical Units)
What is parallax used for?
Why can’t astronomers use
parallax to measure
distances greater than 1000
light-years?
What are the three main
characteristics used to
classify stars?
Name the 5 sizes of stars
from largest to smallest:
What does a star’s color
reveal?
Name the colors of the stars
from coolest to hottest:
What does a star’s
brightness depend on?
What is apparent
magnitude?
What is absolute magnitude?
What is the HertsprungRussell Diagram? What does
it show?
It would take you 4.2 years to travel to Proxima Centauri
The distance that light travels in one year.
The apparent change in position of an object when you look
at it from different places.
Parallax is used to measure distances to nearby stars.
The apparent shift of the star at that distance is so negligible
that you cannot measure any change in position.
Stars are classified by temperature, magnitude (brightness),
and size.
Supergiant star, giant star, medium-sized star, white dwarf
star, neutron star
A star’s color reveals its temperature.
Red, yellow - white, blue - white
Brightness depends on the star’s size and temperature.
It’s brightness as seen from Earth. Apparent brightness is
how bright it appears to be from Earth, not how bright it
actually is.
Absolute magnitude is how bright the star is at a standard
distance from Earth.
It is a diagram or graph that compares the relationship
between a star’s temperature and its brightness (magnitude).
90% of all stars are in the main sequence. In the ain
sequence, the hotter the star, the brighter it is. Not all star’s,
however, follow that pattern. While some star’s are very
hot, they are very dim (white dwarfs) and while some stars
are very bright, they are cool (red giants).
Summary