Stellar process
Pre-Main-Sequence Evolution
The stage between a protostar and a fully-fledged star. Still contracting and drawing energy from gravity rather than fusion, the young star — a T Tauri star at low mass, a Herbig Ae/Be star at higher mass — is wrapped in an accretion disc and drives energetic jets, until its core grows hot enough to ignite hydrogen.
Stars, stages & concepts
Across stellar astrophysics
Knowledge connections
- Associated withStar Formation
- Associated withStar Formation
- Associated withMain-Sequence Evolution
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.