Question

what type of star is in spectral class K and has a luminosity of 10^6
A. White Dwarf
B. Red Giant
C. Red Supergiant
D. Blue Giant

Which one is correct?

Answer 1

A star in spectral class K with a luminosity of \(10^6\) times that of the Sun is most likely a **Red Giant**.

- **White Dwarf**: These are small, dense stars that have lost their outer layers; they are not nearly as luminous.
- **Red Giant**: Stars in this category are large and cool, and they can have high luminosities, ranging from hundreds to millions of times that of the Sun.
- **Red Supergiant**: These stars are even larger than red giants but generally have spectral classes of M rather than K.
- **Blue Giant**: These stars are hot and luminous but are classified with spectral classes O or B, not K.

Given this information, the correct answer is **B. Red Giant**.