3: Stars and Light
- Page ID
- 115276
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Coded into the light is a wide range of information about what stars are like and how they work. If we can decipher this code and read the messages it contains, we can learn an enormous amount about the cosmos without ever having to leave Earth.
By the end of this section, you will be able to:
- Describe the relationship between wavelength, frequency, and speed of light
- Discuss the particle model of light and the definition of photon
- Describe the difference between luminosity and apparent brightness
- List the regions of the electromagnetic spectrum
- Describe how each part of the spectrum interacts with Earth's atmosphere
- Describe the connection between the light emitted by an object and its temperature
- Compare the relative temperatures of stars based on their colors
Thumbnail: This spectacular group of young stars is the open star cluster NGC 3766 in the constellation of Centaurus (The Centaur). ("Star cluster NGC 3766," ESO, CC BY 4.0 via Wikimedia Commons)