Astronomers Initially Had Difficulty Identifying the Emission Lines in Quasar

question 57

Multiple Choice

Astronomers initially had difficulty identifying the emission lines in quasar spectra at optical wavelengths because

• A) the emission lines were smeared out by the extremely high speed of the quasars, making them hard to measure.
• B) the emission lines were from ionized atoms that had not been seen before.
• C) the emission lines were found to be created from elements that do not exist on Earth.
• D) no one expected to see the pattern of spectral lines characteristic of the ultraviolet hydrogen spectra in the visible region.

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