What continuous battle defines a star's existence?
Answer
Inward crush of gravity and outward pressure from thermonuclear reactions
A star's life is a sustained equilibrium maintained between the inward force exerted by gravity and the outward pressure generated by ongoing thermonuclear reactions in its core.

Frequently Asked Questions
What process is responsible for forging elements heavier than hydrogen and helium deep within stars?What continuous battle defines a star's existence?What defines the main sequence phase of stellar evolution?What factor determines almost entirely the fate and elemental output of a star?What do stars with masses less than about eight times that of the Sun expand into after exhausting core hydrogen?Why does the formation of an iron core stop energy generation in massive stars?What catastrophic event is triggered when the iron core collapses?What mechanism is required to create elements heavier than iron during a supernova explosion?What is the primary mechanism stars use to distribute newly forged elements across the cosmos?Besides supernovae, what event generates extreme conditions necessary for intense *r*-process element creation?