Assertion: nebula's material | /r/HasProperty | dense
Facets:
value: sufficiently
type: DEGREE
Source sentences:
text: This only occurs when the material is sufficiently dense and compact, indicating that it has been produced by the progenitor star itself only shortly before the supernova occurs.
text: Like other dark nebulae, the Dark Horse Nebula consists of material that is dense enough to prevent light from background stars penetrating them, thus making them stand out against the star fields behind.