Question

What is a white dwarf star?

A) large, planetary object, such as Jupiter
B) star of about the same size (diameter) as Earth
C) star that is significantly smaller than a giant or supergiant star
D) main-sequence star with a surface temperature near 12,000 K

Answer 1

A white dwarf star is a dense, Earth-sized dying star with a surface temperature around 12,000 K and a mass about half that of the Sun.

Step-by-step explanation:

A white dwarf star is an astronomical object that represents the final evolutionary state of stars not massive enough to become neutron stars or black holes. About the same size as Earth, a white dwarf possesses a mass roughly 0.57 times that of the Sun, but with a much smaller radius—only about 1.4% of the Sun's, which leads to an incredibly high density. These characteristics make answer option 'B' correct: a star of about the same size (diameter) as Earth. A typical white dwarf, like 40 Eridani B, has a surface temperature around 12,000 K, a luminosity far less than the Sun's, and is ultimately a dying star, incapable of further nuclear fusion.