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

The two correct answers are:

- Spherical shape
- Diffuse edges

What does it mean to characterize a nebula as diffuse?(1 point) Responses Its edges have clear boundaries. Its edges have clear boundaries. It reflects only visible radiation. It reflects only visible radiation. Its edges do not have clear boundaries. Its edges do not have clear boundaries. It reflects only non-visible radiation.

To characterize a nebula as diffuse means that its edges do not have clear boundaries.

What causes a supernova?(1 point) Responses force of gravity force of gravity energy of a nebula energy of a nebula energy of heat energy of heat force of a nebula

A supernova is caused by the force of gravity.

How are nebulae and stars related? Select the three correct answers.(2 points) Responses Stars explode to form nebulae. Stars explode to form nebulae. Nebulae explode to form stars. Nebulae explode to form stars. Nebulae form from stars. Nebulae form from stars. Stars form from nebulae. Stars form from nebulae. Stars are pulled toward nebulae. Stars are pulled toward nebulae. Nebulae are found inside stars.

To identify a planetary nebula, you should look for two specific characteristics:

1. Spherical Shape: Planetary nebulas generally have a round or spherical shape. This is due to the material from the dying star being ejected in a symmetric manner, creating a shell-like structure.

2. Diffuse Edges: The outer edges of a planetary nebula should appear blurred or hazy. This is because the gas and dust expelled by the dying star create a glowing, cloud-like structure that is not sharply defined.

Therefore, the two correct answers are:

1. Spherical shape
2. Diffuse edges