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Polio
Protostar
The shapes that collapsing nebula take are a result of a combination of haphazard directions of movement and force responding to the initial motivating nudge from some external force and gravitational attraction and formation of clumps with in the nebula. The shape seen i.e. a blob, elliptical, etc. is in all probably a function of time with regard to the evolving motion and gravitational organization of matter with in the nebula.
The collapsing gas and dust cloud began to spin and form a disk.
If enough matter comes together close enough, the collapse itself will generate enough heat (and pressure) for nuclear fusion. In other words, a star is created.
Gravity works with Pressure to keep a Nebula from collapsing.
Gravity and gas.
If the nebula is gravitationally unstable, it collapsing & forming stars!
the pressure pushes the nebula together just like magnets to keep it from falling or collapsing, and the gravity pulls the exess debri into the nebula to keep it packed tight.
Gravity
Polio
Polio
gravity maybe?
Protostar
The shapes that collapsing nebula take are a result of a combination of haphazard directions of movement and force responding to the initial motivating nudge from some external force and gravitational attraction and formation of clumps with in the nebula. The shape seen i.e. a blob, elliptical, etc. is in all probably a function of time with regard to the evolving motion and gravitational organization of matter with in the nebula.
Gravity and Inertia
A nebula is a cloud of dust and gas. I'm not sure exactly what you mean by "unstable" in this context, since I don't know what you consider "stable". Nebulae are dynamic, changing in response to gravitational forces and radiation pressure; the only way I can think of for one to be "stable" would be if the gravitational forces exactly balanced out the radiation pressure, which would just by the nature of things have to be metastable at best.