The star P Cygni (in the constellation Cygnus,the Swan)is surrounded by an extensive low-density atmosphere.It has a bright,continuous spectrum with many narrow,dark absorption lines and a few bright emission lines.The dark absorption lines are produced by:
A) only the part of the low-density atmosphere that is between Earth and the surface of the star.
B) the hot, low-density atmosphere of the star emitting light in all directions.
C) all parts of the star, the stellar surface, and the atmosphere, equally.
D) the hot, dense, opaque gas of the star's surface.

Question

Quizplus · Accepted Answer

The dark absorption lines are produced by the part of the low-density atmosphere that is between Earth and the surface of the star, as it absorbs specific wavelengths of light from the continuous spectrum emitted by the star's surface.

The Star P Cygni (In the Constellation Cygnus,the Swan)is Surrounded