How do emission and reflection nebulae differ?

Question

hard line edges
contain remnants of stars
the presence of young stars
interactions with light

Answer 1

Emission and reflection nebulae differ in several ways:

1. Hard line edges: Emission nebulae have sharp, well-defined edges, while reflection nebulae have more diffuse boundaries.

2. Contain remnants of stars: Emission nebulae are often associated with regions of active star formation, where massive, young stars emit intense ultraviolet radiation that ionizes surrounding gas, causing it to fluoresce and emit light. These nebulae contain ionized gas and plasma. On the other hand, reflection nebulae do not contain ionized gas but instead consist of dust grains reflecting the light of nearby stars. They do not involve remnants of stars.

3. The presence of young stars: Emission nebulae are typically found in regions of active star formation, where young and massive stars are present. The intense ultraviolet radiation emitted by these young stars causes the surrounding gas to light up. In contrast, reflection nebulae are often associated with regions where young stars have recently formed, and their light is being reflected off dust particles.

4. Interactions with light: Emission nebulae emit their own light due to the ionization of gas by nearby hot stars. They often appear in vibrant colors, such as red, blue, or green, depending on the type of gas present. In contrast, reflection nebulae do not emit their own light but instead reflect the light of nearby stars, resulting in a bluish appearance.

In summary, emission nebulae have well-defined edges, contain ionized gas, are associated with active star formation, and emit their own light. On the other hand, reflection nebulae have more diffuse boundaries, consist of dust reflecting the light of nearby stars, are associated with recently formed young stars, and do not emit their own light.