When astronomers look for evidence of hydrogen gas in the spectra of the Sun, the planets, or the nearby stars, the positions of the spectral features or "lines" due to hydrogen are in
A) a pattern in which the positions of the lines depend on the temperature of the source.
B) the same pattern for the Sun and for planetary sources but very different for stars at larger distances because of absorption of light by the interstellar matter.
C) the same characteristic pattern as seen in the laboratory, a pattern unique to hydrogen.
D) a pattern that depends on the location of the planet or star and that can be reproduced only with difficulty in the laboratory.

Question

Quizplus · Accepted Answer

The positions of the spectral lines due to hydrogen are determined by the energy levels of the hydrogen atom, which are the same everywhere. This results in a characteristic pattern unique to hydrogen that can be observed both in astronomical objects and in laboratory experiments, regardless of the source's temperature, location, or intervening matter.

When Astronomers Look for Evidence of Hydrogen Gas in the Spectra