The spectrum of a star shows these absorption line characteristics: very strong H, weaker Mg II and Si II, and no He I or Ca II lines. What is the spectral type of this star?
A) B
B) G
C) K
D) A

Question

Quizplus · Accepted Answer

The presence of very strong hydrogen lines with weaker magnesium (Mg II) and silicon (Si II) lines, and the absence of helium (He I) and calcium (Ca II) lines, are characteristic of an A-type star. A-type stars are known for their strong hydrogen lines, which dominate their spectra.

The Spectrum of a Star Shows These Absorption Line Characteristics