The remains of type II supernovae (massive star, core collapse supernovae) are seen in the sky as
A) nebulae that are shrinking as the central mass pulls them in.
B) nebulae that are expanding at thousands of kilometers per hour.
C) nebulae that are stellar nurseries.
D) white dwarfs.
E) white holes.

Question

Quizplus · Accepted Answer

The remains of type II supernovae are seen in the sky as expanding nebulae. These supernovae occur when a massive star undergoes a core collapse, leading to a rapid expulsion of material from the outer layers of the star, and the creation of a neutron star or black hole in the core. The expanding nebula, also known as a supernova remnant, is made up of this ejected material and can be observed in the electromagnetic spectrum at various wavelengths.

The Remains of Type II Supernovae (Massive Star, Core Collapse