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sjp9220
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There are red giants, blue giants. white dwarfs, red dwarfs, brown dwarfs, etc., etc., etc,... Why? do they have different chemistries? Are they each at different stages in their lives? Is there a combination of reasons?
Drakkith said:It's a combination of age and mass mostly. Smaller mass stars follow different life-cycles than higher mass stars. For example, a star of 0.2 solar masses will live a very, very long time but will never be able to do anything besides turn hydrogen into helium in its core. As it ages and runs out of fuel, turns into a white dwarf, and then starts to cool off
Chronos said:Since we don't know what any star [aside from the sun] actually looks like
Drakkith said:igniting helium fusion in its core. It then undergoes a series of events that ping-pong it back and forth between expansion and contraction phases, moves up from burning helium to burning heavier and heavier elements, until finally it explodes as a type-II supernova.
The only difference between these two stars is their initial mass, yet this single difference causes a drastic change in their overall life-cycle. While different compositions can also create differences in their life-cycles, these are less drastic by comparison.
Chronos said:Are those dark/light blotches Antares-spots?
sjp9220 said:There are red giants, blue giants. white dwarfs, red dwarfs, brown dwarfs, etc., etc., etc,... Why? do they have different chemistries? Are they each at different stages in their lives? Is there a combination of reasons?
OH o.k., so you're saying that the reason their are blue stars, red, white, etc is just a matter of mass in their initial ignition? Thank you.Drakkith said:It's a combination of age and mass mostly. Smaller mass stars follow different life-cycles than higher mass stars. For example, a star of 0.2 solar masses will live a very, very long time but will never be able to do anything besides turn hydrogen into helium in its core. As it ages and runs out of fuel, turns into a white dwarf, and then starts to cool off until, many billions of years later, it finally cools off to ambient temperature in space (less than a few kelvin). However, a star of 10 solar masses ages extremely rapidly, staying on the main sequence for only a few million years or so before igniting helium fusion in its core. It then undergoes a series of events that ping-pong it back and forth between expansion and contraction phases, moves up from burning helium to burning heavier and heavier elements, until finally it explodes as a type-II supernova.
The only difference between these two stars is their initial mass, yet this single difference causes a drastic change in their overall life-cycle. While different compositions can also create differences in their life-cycles, these are less drastic by comparison.
sjp9220 said:OH o.k., so you're saying that the reason their are blue stars, red, white, etc is just a matter of mass in their initial ignition?
Drakkith said:It's a combination of age and mass mostly.
sjp9220 said:OH o.k., so you're saying that the reason their are blue stars, red, white, etc is just a matter of mass in their initial ignition? Thank you.
Drakkith said:Initial mass, current mass, age, and a few other factors. Like I said, the main factors are initial mass and age. The Sun will swell into a red giant in a few billion years, during which it will be much more reddish than it is now, despite having nearly the same mass as it initially had.
stefan r said:Metalicity is a major factor.
The main reason for the variety of stars in the universe is due to the different masses and compositions of the clouds of gas and dust from which they are formed. These variations in mass and composition lead to different physical processes and conditions, resulting in the formation of different types of stars.
The brightness of a star is primarily determined by its size, temperature, and distance from Earth. Larger and hotter stars tend to appear brighter as they emit more light and energy. The distance from Earth also plays a role, as stars that are closer will appear brighter than those that are further away.
Stars form through the gravitational collapse of a cloud of gas and dust. As the cloud collapses, it heats up and begins to rotate, forming a protostar. The protostar continues to grow by accreting more matter until it reaches a critical temperature and density, igniting nuclear fusion in its core. The type of star that forms depends on its initial mass and composition, and how it evolves over time is determined by its mass and internal processes.
The main factors that determine a star's lifespan are its mass and composition. The more massive a star is, the faster it burns through its fuel and the shorter its lifespan. The composition of a star also affects its lifespan, as stars with higher amounts of heavier elements tend to have shorter lifespans due to increased nuclear reactions and energy output.
The different types of stars provide valuable information about the universe and its history. By studying the properties and evolution of different types of stars, scientists can better understand the processes and conditions that led to the formation of our universe, as well as gain insight into the future of the universe and the fate of stars. Additionally, different types of stars play important roles in the creation and distribution of elements, which are essential building blocks for the formation of planets, moons, and life itself.