Major theme: Our knowledge of the universe beyond Earth comes from light emitted, absorbed, or reflected by astronomical objects.
Learning Objectives:
- Describe the wave and particle properties of light, and describe the electromagnetic spectrum.
- Describe how to measure the chemical composition of distant objects using the unique spectral lines of different types of atoms.
- Describe the Doppler effect and how it can be used to measure the motion of distant objects.
- Explain how the spectrum of light that an object emits depends on its temperature.
- Differentiate luminosity from brightness, and illustrate how distance affects each.
Outline:
- Light brings us the news of the Universe.
- The speed of light
- Light as an electromagnetic wave
- Characterizing waves
- The Electromagnetic (EM) spectrum
- Light as a particle
- The quantum view of matter explains spectral lines.
- Atomic structure
- Atomic energy levels
- Emission spectra
- Absorption spectra
- spectral fingerprints of atoms
- Excitement and Decay
- Temperature affects the spectrum of light that an object emits
- Equilibrium and balance
- Temperature, Luminosity, and color
- Blackbody Laws
- The brightness of light depends on the luminosity and distance of the source.
Activities & Assignments:
Topic class notes
Read Textbook: Chapter 5, Radiation and Spectrum
LT: The EM Spectrum (see notes folder)
Wien’s Displacement Law exercise (see questions in notes folder)
LT: Types of Spectra (see notes folder)
Lab 5: Light and Telescope Lab (see lab manual)
Extra Stuff:
Chromoscope – a multi-wavelength view of our galaxy.
Atomic Spectra: The spectroscopes and emission and absorption spectra explained. The spectroscope is the most important tool in astronomy.
