How do clusters of (or single) stars ignite within a nebula?
When the cosmic dust, ions, particles known commonly as radioactive decay particles from raduations a-z and everything else in there come together through gravity to form a bunch of stars, how is 'ignition' started, and what determines the boundary between a star and the surrounding nebula? Is it forced away by a stars solar wind? Why doesn't it blast its self apart when fusion behind anyways?
- daniel gLv 72 months agoFavorite Answer
Gasses and dust are matter which has mass. This collects for gravity and forms entities of mass. as this mass** becomes more dense, there is a point where sheer pressure causes a fusion reaction of this mass and becomes a giant reactor we call a star.
A supernova not unlike a mini big bang just creates a nebula of gasses and dust and the process repeats,,like a star is reborn.
The energy involve spans the entire electromagnetic spectrum we can see with radio telescopes and the nebula with optical telescopes. Crab nebula is a prime example.
The hot you are seeing is the corona of a star emitting radiation and photons in the form of solar wind. Not enough force in that to overcome the gravity of a star and constantly draws in more matter and gasses.
**A lot of hydrogen fusing into helium.
- 2 months ago
As stars collect matter, they begin to heat at their cores. As more matter falls in, the pressure and temperature climb - until finally it reaches the threshold of fusion.
- RetiefLv 72 months ago
A star "ignites" when it has enough mass that gravity forces fusion at its core.
- ElaineLv 72 months ago
Once gravity begins to pull the particles to come together pressure begins to build. As gravity increases it causes more mass to be accumulated, thus pressure keeps increasing. As pressure increases so does the temperature. Once the temperature reaches a few million degrees Celsius fusion begins and a star is born. The determining factor of the distance between the new born star is the amount of gas in the nebula and the amount of gas the star accumulates. Once the star ignites it blows away the nearby gas.
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- YKhanLv 72 months ago
The stellar nebula are cold, near absolute zero. There are no free ions there, every nucleus is paired up with an appropriate number of electrons. Because the particles are so cold, there is barely any movement within the nebula, so gravity has a chance to take hold and start pulling these things together. There will inevitably some parts of the cloud that are a little bit more dense than other parts. Those slightly overdense areas will begin attracting more and more material towards it through gravity, and then eventually enough will accumulate that they will become the proto-stars. The fusion process doesn't start until the core achieves a certain mass, usually 10% the mass of the Sun. At that point the outer layers of the proto-stars will be much more massive than the core mass (at least 9:1), so the fusion process cannot blow those things away. However, eventually a stellar wind is set up within the outer layers, and those will begin to blow away the remainder of the nebula near it, thus stopping the star from getting even bigger.
- CarolOklaNolaLv 72 months ago
Radioactive decay is NOT what starts Nuclear fusion. . Gravity alone may not necessarily ignite nuclear fusion. . There often has to another force, either one or .ore bow shock waves from massive stars going supernova or radiation pressure from nearby stars PLUS gravitational collapse that raises theopposite force of PRESSURE and temperature I the core high enough for nuclear fusion of FOUR hydrogen protons to fuse into ONE helium nucleus with to prptons and 2 neutrons.
Whether the star has enough mass to maintain nuclear fusion in the long enough to reach hydrostatic equilibrium and move onto the ai sequence or become a hybrid brown dwarf star - planet is a different topic. Radioactive radiation is NOT required. https://en.m.wikipedia.org/wiki/Proton%E2%80%93pro...
- NyxLv 72 months ago
Gases fall together under the influence of gravity. As more gases climb together, pressure builds up. Eventually, the increasing pressure builds up the temperature to the point where fusion is initiated.
And a star is born.
The stars maintains its fusion activity through the balance of gravity pulling inward, and the pressure of fusion pushing outward.
- D gLv 72 months ago
gravity .. the sun is formed by gas held by gravity as the mass gets to the point the pressure pushes two hydrogen molecule together you have energy released
the molecules keep being pushed together
it is NOT fire it is energy released as light or high energy particles
- Jim MoorLv 72 months ago
If a bunch of stuff comes together, the friction and impacts are sufficient to ignite a sun, I would think it actually be hard for it not to ignite