The Sun's spectrum peaks in the yellow-green region (i.e., this region is the most intense part of its spectrum). The spectrum of Rigel (the star in the knee of Rigel) peaks in the short-wavelength end of the visible spectrum. Compared with the Sun, Rigel is
A) cooler and redder.
B) cooler and whiter.
C) hotter and redder.
D) hotter and whiter.

Question

Quizplus · Accepted Answer

Rigel's spectrum peaking in the short-wavelength end of the visible spectrum (blue/violet) indicates it is hotter than the Sun, whose spectrum peaks in the yellow-green region. Hotter stars emit more light at shorter wavelengths, making them appear bluer or whiter, hence Rigel is hotter and whiter compared to the Sun.

The Sun's Spectrum Peaks in the Yellow-Green Region (I