Explorations: Introduction to Astronomy (Arny), 6th Edition

Chapter 4: Light and Atoms

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  • Astronomers use telescopes to gather light and thereby make dim objects observable.
  • The larger the diameter of the lens or mirror used in a telescope:
    • The greater its ability to gather light
    • The finer the detail that the instrument will show
  • The Earth’s atmosphere interferes seriously with observing.
    • It absorbs and totally blocks many wavelengths.
    • It blurs details.
    • Astronomers use special-purpose telescopes to observe nonvisible wavelengths. Many of these are in orbit, so they are not affected by blurring or atmospheric absorption.

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