The birth of stars occurs in a nebula or cloud of gas and dust in space, these are often formed fro the death of large stars. what two factors trigger the collapse of these clouds to form a new star?

Gravity and Heat

"...star formation begins when part of the interstellar medium--one of the cold, dark clouds... starts to collapse under its own weight. The cloud fragment heats up as it shrinks, and eventually its center becomes hot enough for nuclear burning to begin. At that point, the contraction stops, and a star is born."

Answer (prosecution);