What factor is key, alongside vast size, in allowing dense clouds to maintain structural integrity over cosmic timescales?

Answer

Very cold temperatures reducing the thermal motion of particles.

The extremely cold temperatures associated with molecular clouds slow down the random thermal motion of the gas particles, allowing gravity to effectively counteract the tendency of the material to disperse over cosmic timescales.

What factor is key, alongside vast size, in allowing dense clouds to maintain structural integrity over cosmic timescales?
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