<Tr> <Td> Accretion Initial mass function Jeans instability Kelvin--Helmholtz mechanism Nebular hypothesis Planetary migration </Td> </Tr> <Tr> <Td> Star portal </Td> </Tr> <Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul>

Where does most star formation occur in the milky way galaxy at present