Put these objects in the correct order from largest to smallest: Star Galaxy Planet Universe

Basic Structure (largest to smallest) Universe

Galaxy

Solar System (Stars)

Planets

Galaxies A collection of billions of stars, gas, and dust, all held together by gravity Classified by shape into:

Elliptical

Spiral

Barred Spiral

Irregular

Milky Way Galaxy Spiral Galaxy Our solar system located on an arm, about 2/3 out from the center

Nuclear Fusion Converts lighter elements into heavier elements Fuels a star

Star Life Cycle

The life cycle of a star depends on its mass when it forms.

Nebula – Gas and dust where stars form

Protostar – Initial stage of a star

Main Sequence Star – Mid life for a star

Red Giants – Older stars

Red Supergiants – older stars that are super massive

Supernova – Exploding star

Planetary Nebula – After a star explodes

White Dwarf – dead star

Neutron Star – massive dead star

Black Hole – supermassive dead star

Answer the following in your notes 1. What will the sun become when it reaches old age? 2. What type of star can become a black hole? 3. Predict what will happen to the sun when it reaches old age

How do we categorize stars? Think pair share: are all stars in the universe similar to the sun? If so why, if not what characteristics might be different with different stars

Luminosity Measures how bright a star would be in relation to the sun, if all stars were the same distance from the observer. The luminosity of a star is related to its size, color, and temperature.

Temperature and Color How hot the surface of a star is. Hottest temperatures are blue, coolest are red.

Hertzsprung-Russel Diagram is a scatter plot of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their stellar classifications or effective temperatures.

PAGE 15 1 1 1 1 1 1 1 1 1 1

Hottest Color? Blue

Coolest Color? Red

What is the color of our Sun? Yellow

Brightest and hottest stars? Blue Supergiants

Coolest and dimmest stars? Red Dwarfs

Procyon B is a: White Dwarf

Rigel is a: Blue Supergia nt

Betelgeuse is a: Red Supergia nt

Barnard’s Star is a: Red Dwarf

Our Sun and Alpha Centauri are: Main Sequence