Bow shock around the very young star LL Ori.
Stars form in dense molecular clouds within galaxies. These clouds of dust and gas obscure the early stages of stellar formation from optical telescopes. Fortunately recent advances in radio and infrared astronomy now allow astronomers to peer inside these clouds and gain a greater understanding of the processes involved in starbirth. Computationally intensive computer simulations also allow them to model the processes and test the results against observations.
Gravity is the force responsible for stellar formation and the mass of material that forms at star largely determines its life and fate.