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Marcus1122
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What powers a star?
Drakkith said:Gravitational contraction is the sole remaining source of energy for stars that have exhausted their fuel. Once a star reaches a point where it can no longer contract, such as in white dwarfs, it simply cools off until it reaches ambient temperature of around 2 kelvin. Note that no stars have had long enough to cool off to 2 kelvin. I believe the oldest and coolest white dwarf ever found was somewhere above 3,000 k.
Marcus1122 said:You didn't answer my question what fuels after nuclear fuel nuclear property keeps it staple but what keeps it going
Marcus1122 said:Nuclear fuel is the last stand for a star to hold it's mass against gravity
What powers it after thatDrakkith said:Certainly. What about it?
Marcus1122 said:What powers it after that
Marcus1122 said:Is it just the mass of the star left that that leaves this massive amount of gravity
Photon energy is the energy carried by a single photon. The amount of energy is directly proportional to the photon's electromagnetic frequency and inversely proportional to the wavelength. The higher the photon's frequency, the higher its energy. Equivalently, the longer the photon's wavelength, the lower its energyDrakkith said:You're bouncing around different concepts. A star emits light because it is hot. It reaches such a high temperature because, during its initial formation, gravitational contraction of its parent gas cloud heats up the cloud to millions of kelvin in the core. This in turn ignites fusion, turning the cloud into a star and providing the energy needed to keep the star in its present main-sequence state for billions of years. Once this fuel runs out, the star continues to collapse. The collapse process itself generates heat, which is radiated away from the star as light and other forms of EM radiation. Once all of the available gravitational potential energy of the star has been exhausted, meaning that it has collapses to the point that it cannot collapse any further, it has run out of energy sources and will gradually cool as its energy is carried away into space by EM radiation.
The gravity of the star is always due to its mass, and only a tiny fraction of its mass is converted into energy and radiated away.
Yes. Until they run out of fuel.Marcus1122 said:All stars produce light (and other kinds of energy) through nuclear reactions, using the energy stored in the tiny nucleus at the center of atoms. These reactions make the star so hot that it glows—it's like an enormous ball of fire, giving out light and heat.
Relevance?Marcus1122 said:Photon energy is the energy carried by a single photon. The amount of energy is directly proportional to the photon's electromagnetic frequency and inversely proportional to the wavelength. The higher the photon's frequency, the higher its energy. Equivalently, the longer the photon's wavelength, the lower its energy
Marcus1122 said:All stars produce light (and other kinds of energy) through nuclear reactions, using the energy stored in the tiny nucleus at the center of atoms. These reactions make the star so hot that it glows—it's like an enormous ball of fire, giving out light and heat.
Marcus1122 said:Photon energy is the energy carried by a single photon. The amount of energy is directly proportional to the photon's electromagnetic frequency and inversely proportional to the wavelength. The higher the photon's frequency, the higher its energy. Equivalently, the longer the photon's wavelength, the lower its energy
But it's not the same and not as strong as the star generating the heat or energyDaveC426913 said:Relevance?
Marcus1122 said:But it's not the same and not as strong as the star generating the heat or energy
What is 'it'?Marcus1122 said:But it's not the same and not as strong as the star generating the heat or energy
Marcus1122 said:What powers a star?
Marcus1122 said:All stars produce light (and other kinds of energy) through nuclear reactions, using the energy stored in the tiny nucleus at the center of atoms. These reactions make the star so hot that it glows—it's like an enormous ball of fire, giving out light and heat.
When a star runs out of nuclear fuel, it can no longer produce energy through nuclear fusion. As a result, the core of the star collapses and the outer layers expand, causing the star to become a red giant or a supergiant.
As the nuclear fusion process slows down or stops, the temperature of the star's core decreases. This can cause the outer layers of the star to cool and expand, resulting in a decrease in the overall temperature of the star.
No, a star cannot continue to shine without nuclear fuel. Nuclear fusion is what powers a star and when the fuel runs out, the star can no longer produce energy to sustain itself.
The fate of a star after it has exhausted its nuclear fuel depends on its mass. If the star is relatively small, it will become a white dwarf. If the star is more massive, it may become a neutron star or a black hole.
The amount of time it takes for a star to exhaust its nuclear fuel depends on its mass. Smaller stars can burn their fuel for billions of years, while more massive stars may only last a few million years. The exact duration also depends on the rate of nuclear fusion within the star.