| Eventually, a protostar becomes dense enough to ignite nuclear reactions at its core, a sign that a bona fide star has been born. |
| As the protostar continues to collapse due to gravity, it will attract more atoms and continually increase in mass and density. |
| After all, the Sun was presumably once a protostar too. |
| Jets and outflows carry off much of the energy and angular momentum that is released as the accretion disk spirals into the central protostar. |
| The cloud slowly collapses due to gravity, a protostar is formed and soon the internal temperature rises high enough to ignite nuclear fusion. |
| It became known as the Becklin-Neugebauer object and was later determined to be the first protostar to be directly observed. |
