Assertion: nebula's hydrogen | /r/HasProperty | ionized
Facets:
value: mostly
type: DEGREE
Source sentences:
text: Emission Nebulae are those that emit spectral line radiation from ionized gas, and are often called HII regions because they are largely composed of ionized hydrogen.
text: They are H II regions, because mostly hydrogen is ionized, but planetary are denser and more compact than nebulae found in star formation regions.
text: Technically they are HII regions, because most hydrogen will be ionized, but they are denser and more compact than the nebulae in star formation regions.