protostar

A protostar is a celestial body in the early stages of star formation. It forms from the gravitational collapse of dense regions within molecular clouds. As material falls onto the protostar, it forms an accretion disk around it, and the protostar grows in mass.12

Initially, the protostar's contraction is halted by thermal pressure. Radiation struggles to escape the opaque interior, causing heat buildup. The protostar continues to grow by accreting surrounding matter. This process generates intense radiation from the infalling gas and dust, making protostars visible primarily as infrared objects.1

Eventually, powerful stellar winds from the protostar clear away the surrounding gas and dust, halting the accretion process. This outflow often takes the form of jets squiring from the poles, creating bipolar outflows. As the protostar contracts further, its core temperature rises, eventually igniting hydrogen fusion and marking its transition to a main-sequence star.1