3. Birth of star
A star is “born” when the contracting
gas and dust become so hot that
nuclear fusion begins to occur.
How long a star lives depends on how
much mass it has. Stars with less mass
burn their fuel more slowly and last
longer than stars with more mass.
4. star’s surface temperature
determines the amount of
visible light given off and the
color we perceive the star to
be.
yellow stars produce light of
all color.
5. White stars give off roughly
equal amount of every kind of
light, and blending of these
colors makes them appear
white.
The hottest type of star
appears blue or white.
The coolest type of star
appears red.
6.
7.
8.
9. Have mass from 8
to 100 times of our
star.
Luminosity is
about 1000 to
50000 times
brighter than our
sun
Life-10 to 20
million years
10. super giant
It is a Most massive star.
its mass is about 10 to70 solar mass
Its luminosity is from 30,000 to
100,000 times of solar luminosity
It has a short life time - about 3o
million years therefore it is called
tenuous stars.
12. Have mass about 3.8
times greater than our
Sun.
Diameter - 15 miles
It lies very close to the
minimum size predicted
for black holes that
originate from dying stars
13. lies in the Centre of nebula.
Having surface temperature up
to 250,000.
Is more than 30 times hotter and
250 times brighter than the Sun.
14. Itis also known as the Dog
Star.
The sixth closest star to
Earth.
Magnitude-1.46.
Is 8.7 light years distant.
15. V838 Monocerotis reveals
dramatic changes in the
illumination of surrounding dusty
cloud structures. The effect, called
a light echo, unbeiled never-
before-seen dust patterns when
the star suddenly brightened for
several weeks in early 2002.
16. When a star begins to run out of
fuel, the center of the star
shrinks and the outer part
expands. The star becomes a
red giant or supergiant
When a star runs out of fuel it
becomes a white dwarf, a
neutron star, or a black hole.
17. All main sequence
stars eventually
become red giants
or supergiants,
what happens next
depends on the
mass of the star.
