What property of stars determines their life cycle?
The property of stars that determines their life cycle is their mass.
The property of stars that determines their life cycle is their mass.
The property of a star that determines its life cycle is its mass. The mass of a star dictates the amount of fuel it has for nuclear reactions, which in turn governs how long it lives and the stages it goes through during its life.
To determine the life cycle of a star based on its mass, you can refer to the Hertzsprung-Russell (H-R) diagram. This diagram plots the luminosity (brightness) of stars against their temperature or spectral type. In general, there are three main types of stars with different life cycles:
1. High-Mass Stars (Greater than 8 times the mass of the Sun): These massive stars have enough mass to initiate nuclear fusion of heavier elements, such as helium, carbon, and oxygen. They have short lives, ranging from a few million to a few tens of millions of years. Throughout their lives, they go through stages like main-sequence, red giant, and eventually supernova or a hypernova explosion.
2. Medium-Mass Stars (Between 0.5 and 8 times the mass of the Sun): These stars, including our Sun, follow a different life cycle. They spend most of their lives as main-sequence stars, where hydrogen fuses to form helium in their cores. As they exhaust their hydrogen fuel, they expand and become red giants. Eventually, they shed their outer layers and become white dwarfs, slowly cooling down over billions of years.
3. Low-Mass Stars (Less than 0.5 times the mass of the Sun): These stars, also known as red dwarfs, have the longest lifespans. They burn their hydrogen fuel slowly, making them live for tens of billions or even trillions of years. They stay in the main-sequence phase for most of their lives and eventually become white dwarfs, similar to medium-mass stars.
Understanding the mass of a star helps determine its life cycle as it ultimately governs the balance between the gravitational forces and the energy produced by nuclear reactions within the star's core.