According to present understanding,a nova is caused by
A)hydrogen fusion on the surface of a white dwarf.
B)carbon fusion in the core of a white dwarf.
C)hydrogen fusion on the surface of a neutron star.
D)a white dwarf that gains enough mass to exceed the 1.4-solar-mass limit.

Question

Quizplus · Accepted Answer

A nova is caused by hydrogen fusion on the surface of a white dwarf. When a white dwarf star has a close companion star, it can accrete material from it. This material accumulates on the surface of the white dwarf and eventually becomes hot and dense enough to ignite hydrogen fusion, causing a sudden brightening in the star's luminosity known as a nova.

According to Present Understanding,a Nova Is Caused by