1. Finish the activity from yesterday CORRECTLY glue the planets

2. Goals for Today’s Lesson
Planets
Order
Classification
Stars
Nebular Theory
Classification
Star Life Cycle

3. Classifying Planets Mercury Venus Earth Mars Jupiter Uranus Neptune
Pluto
Planet Classified:
Location
Inner
outer
Composition
Terrestrial (“solid”)
gas
Size
Inferior
superior

4. Sun = gravity and heat! Classify Planets Inner Outer Small
Dense (rocky)
Solid surface
No or few moons
Warm or HOT temperature
Gas, giants
Low density
Rings (satellites)
Multiple moons
Cooler or COLD temperature
Sun = gravity and heat!

5. Stars and Galaxies
Life Cycle of a Star!!

6. Current night sky over Phoenix, AZ
Ancient Greeks and Roman observed “Patterns in the Sky”
These patterns were called constellations

7. Wait What are Stars? A star is a luminous (shiny) ball of gas
Made mostly
hydrogen and
Helium
dust
held together by its own gravity.

8. Nebular Theory Nebular = large cloud, dust A star is BORN!!!
Nebular becomes so dense and HOT nuclear fusion occurs.
Nuclear fusion = nucleus of atoms are fusing (melting together)
A star is BORN!!!

9. STARS AND GALAXIES Classification Characteristics: 1. Color 2
STARS AND GALAXIES   Classification Characteristics: 1. Color 2. Temperature 3.Size 4. CoMpOsiTiOn (elements) 5. Brightness

10. Classified as G2V Hot Cold G for where it falls on the color spectrum
0-9 to show how far off it’s color is on the O-M scale
I-V to show it “luminosity” shiny!! And size
Main sequence are “dwarf” or small stars that aren’t as bright
Hot Cold

11. This Diagram---shows the life cycle of stars
supergiants
Main sequence
giants
Absolute magnitude
White
dwarfs
temperature

12. O, B, A, F, G, K, and M... (Oh Be A Fine Guy Kiss Me)
and for you guys: Oh Be A Fine Girl Kiss Me!!

13. Star, meaning it’s smaller than a normal star.
Our sun is a
“main sequence”
Star, meaning it’s smaller than a normal star.
And is in the 2nd stage of a star’s life cycle.

14. Waves for Stars Scientists use Spectroscopes
to study the spectra (wavelength) a star emits
The instrument spreads light into different wavelengths

15. What does the color of a star tell us?
How the star is moving
The temperature of the star
The size of the star!
The stage the star is in, in the Star Life Cycle

16. Star Life Cycle
Stars are mainly hydrogen and helium. 1. (In a star) When hydrogen fuses to helium it runs out of energy [heat]
2. The core of the star becomes unstable and begins to expand, cool, and turn red
How a black hole is formed
The core of a massive star that has more than roughly 3 times the mass of our Sun after the explosion will do something quite different. The force of gravity overcomes the nuclear forces which keep protons and neutrons from combining. The core is thus swallowed by its own gravity. It has now become a black hole which readily attracts any matter and energy that comes near it.

17. Depending on the original mass of the star
Average Star (sun)
Helium core turns to carbon and collapses
The outer layers are expelled (BOOM!)
The core remains and looks white
Massive star (huge)
The unstable red core grows bigger
MASSIVE EXPLOSION
Leaving either
An extremely dense star OR
Black hole

19. Grab the Star Life Cycle worksheet
Color it
Attempt to place the Star life cycle in order based off class notes

20. Main Sequence (Small star)
Star Life Cycle Were you right? Now match the description words in the chart to your worksheet
Nebular
Main Sequence (Small star)
Red Giant
White Dwarf Planet
Massive Star
Super Red Giant
Super Nova
Neutron Star
Black Hole

21. Why do you care?
The sun is the basis to OUR existence! It also has a life cycle that is going to end one day!! Unless some brave astronomer finds a solution!

22. Path of a star much larger than our sun
A star starts to die when hydrogen runs low:
Giant: A star cools as it expands and starts to glow red. Giants can be more than 10 times larger than the sun.
White dwarf: outer layers escape into space, the star collapses into a dense hot, dim star smaller than Earth.
Path of a star much larger than our sun
Path of our Sun

23. Massive Stars die explosively!!
Supergiant: Massive stars become larger than giants as they leave the main sequence….they can be 100 to 1,000 times larger than the sun.
Supernova: the explosion of a supergiant
Neutron Star: a small dense ball of neutrons that spin after a supernova explosion
Black Hole: the remnants of a supernova that are contracted even more than a neutron star… it is so dense light cannot escape from it.

24. Can you spot the supernova?
These are before-and-after images of a recent supernova event (Supernova 2005cs) in the galaxy M51. Can you spot the bright supernova in the after (right) that wasn’t visible before?
Images used with permission.
© by R. Jay GaBany