A Picture of a Protostar

Protostar Facts for Kids

  • Common Name: Protostar
  • Type of Star: Young Star (stellar evolution phase)
  • Mass: 1 solar mass or less
  • First Discovered: 1966
  • Discovered by: Chushiro Hayashi
  • Examples: V1647 Orionis and HOPS 383

12 Protostar Facts for Kids

  1. A protostar is a young star in the earliest stage of stellar evolution.
  2. A protostar is also known as a YSO or young stellar object.
  3. Astronomers can only detect protostars by infrared or microwave wavelengths.
  4. There are 4 classes of protostars, based on their peak emissions. They are class 0, class I, class II and class III.
  5. A protostar is a class 0 YSO (submillimeter) for about 10,000 years.
  6. A protostar is a class I YSO (far-infrared) for about 100,000 years.
  7. A protostar is a class II YSO (near-infrared) for about 1,000,000 years.
  8. A protostar is a class III YSO (visible) for about 10,000,000 years.
  9. A protostar will graduate to a main-sequence star after the core temperature gets over 10 million Kelvin. That is the temperature that hydrogen fusion operates efficiently.
  10. It can take a protostar millions of years to complete this early stage of stellar evolution.
  11. The time needed for a protostar to graduate to a main-sequence star depends on the mass of the star. The more mass a protostar has, the faster it will become a main-sequence star.
  12. A brown dwarf is a failed star and results from a protostar with less than 0.08 solar mass.

Additional Resources with Protostar Facts