Question

How can a planetary nebula be identified? Select the two correct answers.(1 point)
Responses

spherical shape
spherical shape

diffuse edges
diffuse edges

dark area
dark area

central star remnant

Answer 1

A planetary nebula can be identified by the following two characteristics:

1. **Spherical shape** - Planetary nebulae often exhibit a roughly spherical appearance as they expand in all directions.
2. **Central star remnant** - They typically contain a central star remnant, which is a hot core of gas that is often shining brightly as it emits ultraviolet radiation.

So, the correct answers are "spherical shape" and "central star remnant."