According to N. Imara, the life of a star depends upon which property?

• A. Mass
• B. Temperature
• C. Age
• D. Metallicity

Answer: (A)

Mass sets the whole trajectory of a star’s life. The star’s initial mass determines the gravitational pressure in the core, which drives the core to temperatures and densities hot enough for nuclear fusion to ignite and to sustain itself. The rate at which energy is produced—and thus how quickly the star burns through its fuel—scales strongly with mass. Very massive stars burn fuel rapidly, shine brightly, and exhaust their hydrogen in a relatively brief time, ending in dramatic finales. Low-mass stars fuse fuel more slowly and can endure for many billions of years. Because mass fixes how fast fusion proceeds and what stages the star can reach, it largely decides whether a star ends up as a quiet white dwarf, a sun-like star, or a massive supernova progenitor. Temperature and age are related to this process but do not drive the lifetime themselves, and metallicity mainly tweaks details like opacity and mass loss rather than setting the overall timescale.