A nebula begins as a dense cloud of gas and dust that contracts due to gravity. As pressure and temperature increase, it forms a protostar. When hot enough, fusion reactions begin and a main sequence star is born. Over time, a star will expand into a red giant as fusion outweighs gravity. After swelling to many times its size, a red giant cools and its outer layers form a planetary nebula surrounding the core which shrinks into a white dwarf. For very massive stars, a supernova explosion marks the end, briefly outshining the galaxy before leaving behind a crushed core such as a neutron star or black hole.

2. NEBULA
_____________: A dense cloud of gas and dust

3. gravity
The nebula begins to contract due to __________ and the pressure
PROTOSTAR
and temperature increase and becomes a ________________.

4. fusion
When the temperature gets hot enough, a _______________ reaction
begins and a _______ ____________ star is born.
MAIN SEQUENCE

5. A star loses ____________ during fusion as energy is released. This
mass
decreases the star’s gravity.
RED GIANT
Over time, a star will expand, becoming a ___________ ____________,
when the outward force of ________________ is greater than the
fusion
gravity
inward force of ______________.

6. After swelling to around 300-400 time its size, the red giant cools and
dust
the outer layers of _____ and ______ expand and surround the star.
gas
This planetary body is know as a ___________ ____________.
PLANETARY NEBULA
The core of the star shrinks in size and cools down, becoming a
WHITE DWARF
_________ ____________.
White Dwarf

7. SUPERNOVA
explosion
A ___________________ is an _________________ that marks the end
of a very massive star’s life. When it occurs, the exploding star can outshine
all of the other stars in the galaxy in total for several days and may leave
behind only a crushed core.

8. The life cycle of stars depends on their mass.
BLACK DWARVES
Small and medium stars become __________________ once
they die.
NEUTRON STARS
Larger stars become novae and die as: ______________
A neutron star is an imploded core of an exploded
star made up almost entirely of neutrons. A
teaspoon of their material would weigh more than
the weight of all of cars, buses and trucks in the
Australia
The most massive stars become supernovae and die
as a:
BLACK HOLE
______________________
A black hole is an extremely massive remnant from
which _______ cannot escape
light
http://chandra.harvard.edu/photo/2004/rxj1242/index.html

10. Worksheet :D
**Missing Labels on page 2**
Blue Red

11. 1. What is infra-red technology?
2. How is infra-red technology useful for seeing things in space?
3. Why would we want a telescope on a plane?
4. What are light curves?
5. What does a light curve tell us about a stars life cycle?
6. What is spectral analysis?
7. What does spectral analysis tell us about a star?