Major theme: Star light reveals many clues.
Learning Objectives:
- Explain how the brightness of nearby stars and their distances from Earth are used to determine how luminous they are.
- Explain how astronomers obtain the temperatures, sizes, and composition of stars.
- Describe how astronomers estimate the masses of stars.
- Classify stars, and organize this information on a Hertzsprung-Russel (H-R- diagram).
- Explain how the mass and composition of a main-sequence star determines its luminosity, temperature, and size.
- Differentiate luminosity from brightness, and illustrate how distance affects each.
Outline:
- Astronomers measure the distance, brightness, and luminosity of stars.
- Stereoscopic vision and parallax.
- Distances to nearby stars.
- Luminosity, Brightness, and Distance.
- Temperature affects the spectrum of light that an object emits
- Equilibrium and balance
- Temperature, Luminosity, and color
- Blackbody Laws
- Determining temperature, size, and composition.
- Wien’s Law: color and surface temperature
- Star classification by temperature.
- Composition of stars.
- The Stefan-Boltzmann Law yields sizes of stars.
- The Hertzsprung-Russell Diagram
- Constructing an H-R diagram
- The main sequence stars
- Stars not on the Main Sequence: White dwarfs, Giants, and Super-Giants.
Activities & Assignments:
- Topic class notes
- Read Textbook Chapter 13: Taking the Measure of Stars
- LT pair & share: Size, Luminosity, and Temperature (pg. 55)
- ClassAction: Stellar Properties (Luminosity): lessons 1-5
- LT pair & share: H-R Diagram (pg. 117)
- ClassAction: H-R diagram, lessons 8 & 9
- Lab 3: H-R Diagram
Extra Stuff:
Star Party at Chamberlain Observatory
