How can a planetary nebula be identified? Select the two correct answers.(1 point)
Responses
spherical shape
spherical shape
dark area
dark area
diffuse edges
diffuse edges
central star remnant
spherical shape and diffuse edges
The correct answers are:
1. Spherical shape: Planetary nebulae often have a round or spherical shape. This is due to the expanding shell of gas and dust that is ejected from the central star.
2. Diffuse edges: Planetary nebulae have faint and diffuse edges, which make them appear soft around the edges. This is a distinguishing feature of these types of nebulae.
Dark area and central star remnant are not characteristics used to identify a planetary nebula. Dark areas can be seen in other types of nebulae, and the central star remnant can only be observed once the outer layers of the nebula have dissipated.
To identify a planetary nebula, you can look for the following characteristics:
1. Spherical shape: Planetary nebulae are typically round or spherical in shape. This is because they are formed by the outer layers of a dying star being expelled into space in a spherical shell.
2. Diffuse edges: Planetary nebulae have fuzzy or diffuse edges. This is because the expanding shell of gas emitted by the dying star disperses over time, creating a less defined boundary.
Therefore, the correct answers are:
- Spherical shape
- Diffuse edges