The Life Cycle of Stars The Life Cycle

The Life Cycle of Stars

The Life Cycle of Stars “protostar”

The Life Cycle of Stars “protostar” “Main Sequence” (longest phase in a star’s cycle

The Life Cycle of Stars “protostar” “Main Sequence” “Red Giant”

The Life Cycle of Stars “protostar” “Main Sequence” “Red Giant” “White Dwarf”

The Life Cycle of Stars • Cycle for Massive Star: • Nebula • Main Sequence • Super Red Giant • Neutron Star, Pulsar, or Black Hole forms at end of its life cycle “protostar” “Main Sequence” “Red Giant” “White Dwarf”

Star Phases: Charted on H-R Diagram

Explaining the H-R Diagram • “H” = Hertzsprung • “R” = Russell • graph of temperature and brightness of all stars

A Closer Look at the H-R Diagram

Star Phases: Charted on H-R Diagram • The H-R Diagram shows the relationship between absolute magnitude, luminosity, classification, and effective temperatures of stars. • The H-R Diagram can be used to define different types of stars.

Explaining the H-R Diagram • Temperature: horizontal (bottom) axis. • hotter at left • cooler toward right

Explaining the H-R Diagram • Brightness: vertical (left side) axis. • brightest stars near top • dim stars near bottom

Explaining the H-R Diagram • A star’s position on the diagram will change as it moves from its “birth” to its “death”.

Explaining the H-R Diagram • You. Tube Style

Your Turn to Practice • Get a copy of HR Diagram. Color the different sections of the HR Diagram using colored pencils. Answer questions 115 using your notes and textbook.