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Evidence of the Big Bang

By Scott Azar
Last updated 6 months ago
10 Questions
Cosmic Microwave Background Radiation
In the 1920s, Edwin Hubble's discovery of a pattern in the red shift of light from galaxies moving away from Earth led to the theory of an expanding universe. This expansion implies that the universe was smaller, denser, and hotter in the past. In the 1940s, scientists predicted that heat (identified as cosmic microwave background radiation) left over from the Big Bang would fill the universe. In the 1960s, satellite probes found that cosmic microwave background radiation fills the universe uniformly in every direction, and indicated a temperature of about 3 kelvins (K). This radiation has been cooling as the universe has been expanding.
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1.

Scientists infer that the universe began approximately

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2.

Which graph best shows the relationship of the size of the universe to the temperature indicated by the cosmic microwave background radiation?

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3.

Cosmic microwave background radiation is classified as a form of electromagnetic energy because it

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4.

The current temperature indicated by the cosmic microwave background radiation is (Use the temperature chart on ESRT pg. 13)

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What is the approximate age of the Universe?

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9.

The Doppler effect predicts that light from a source moving away from Earth will be

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10.

Base your answer on the diagram and photograph below and on your knowledge of Earth science. The diagram represents the constellation Ursa Major. One star, Phecda, has been labeled. Letter X represents the location of the Messier 81 galaxy (M81), which can be observed near Ursa Major. The photograph shows the Messier 81 galaxy as viewed through a telescope.





The study of spectral lines from the Messier 81 galaxy suggests that it is moving toward Earth. Identify the color toward which these spectral lines shift when visible light from the Messier 81 galaxy is observed on Earth.