Galactic OB associations
E476479
Galactic OB associations are large, loosely bound groupings of young, massive O- and B-type stars distributed throughout the Milky Way, marking regions of recent and ongoing star formation.
Statements (52)
| Predicate | Object |
|---|---|
| instanceOf |
stellar association
ⓘ
young stellar population ⓘ |
| ageRange |
a few million years
ⓘ
typically less than 30 million years ⓘ |
| composedOf |
B-type stars
ⓘ
O-type stars ⓘ massive stars ⓘ young stars ⓘ |
| dynamicalEvolution | disperse into the Galactic field ⓘ |
| dynamicalState | not in virial equilibrium ⓘ |
| hasEffectOn |
Galactic chemical evolution
ⓘ
Galactic energy budget ⓘ interstellar medium ⓘ large-scale ionization of the ISM ⓘ |
| hasProperty |
contain early spectral types
ⓘ
dominated by massive stars ⓘ gravitationally unbound or marginally bound ⓘ large spatial extent ⓘ loosely bound ⓘ low stellar density ⓘ often associated with H II regions ⓘ often associated with interstellar gas and dust ⓘ often associated with ionized gas ⓘ often associated with molecular clouds ⓘ often associated with reflection nebulae ⓘ short-lived structures ⓘ tracing recent star formation ⓘ |
| locatedIn |
Galactic disk
ⓘ
Milky Way ⓘ spiral arms of the Milky Way ⓘ |
| observedIn |
infrared wavelengths
ⓘ
optical wavelengths ⓘ radio wavelengths via associated gas ⓘ ultraviolet wavelengths ⓘ |
| relatedTo |
H II regions
NERFINISHED
ⓘ
giant molecular clouds ⓘ ionization fronts ⓘ open clusters ⓘ spiral arm structure ⓘ star-forming complexes ⓘ stellar feedback processes ⓘ superbubbles ⓘ supernova remnants ⓘ triggered star formation ⓘ |
| traces | recent star formation in the Galactic disk ⓘ |
| typicalMass | 10^3 to 10^5 solar masses ⓘ |
| typicalSize | tens to hundreds of parsecs ⓘ |
| typicalVelocityDispersion | a few km/s ⓘ |
| usedFor |
mapping spiral structure of the Milky Way
ⓘ
studying early stellar evolution ⓘ studying feedback from massive stars ⓘ studying massive star formation ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.