Assertion: nebula's star | /r/HasProperty | small to produce supernova explosions
Facets:
Source sentences:
text: Stars with masses lower than 8 M ☉ are thought to be too small to produce supernova explosions, and end their lives by producing a planetary nebula instead, while a star heavier than 12 M ☉ would have produced a nebula with a different chemical composition from that observed in the Crab Nebula.