What must occur for an object to be considered a main-sequence star
A)hydrostatic equilibrium
B)nuclear fusion reaction in the core
C)protostar life begins
D)hydrostatic equilibrium and nuclear fusion reaction in the core

Question

Quizplus · Accepted Answer

For an object to be considered a main-sequence star, it must maintain both hydrostatic equilibrium and a nuclear fusion reaction in its core. Hydrostatic equilibrium means that the inward force of gravity is balanced by the outward force of pressure generated by the energy produced in the core. Nuclear fusion releases energy, which generates the necessary pressure to maintain hydrostatic equilibrium. Therefore, only choice D correctly describes what must occur for an object to be considered a main-sequence star.

What Must Occur for an Object to Be Considered a Main-Sequence