Radio Waves with 21-Cm Wavelengths Are Important Because They

question 53

Multiple Choice

Radio waves with 21-cm wavelengths are important because they

• A) allow us to study the deep interiors of stars.
• B) allow us to image magnetic fields directly.
• C) allow us to study neutral hydrogen in the interstellar medium.
• D) is produced by every object in the universe.
• E) is the longest wavelength of light that can be naturally produced.

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