What kind of classifcations are there for nebulae?

Close

Link to this answer

Share this credible answer with others. Simply paste this code into your blog or Web page:

<a href="http://qanda.encyclopedia.com/question/kind-classifcations-there-nebulae-130240.html" >What kind of classifcations are there for nebulae?</a>

Diffuse nebulae and planetary nebulae are two major classifications of these objects. Diffuse nebulae appear as light or dark clouds (called bright and dark nebulae), are irregular in shape, and range up to 100 light-years in diameter. Some bright nebulae, composed primarily of hydrogen gas ionized by nearby hot blue-white stars, radiate their own light; they are called emission nebulae and are characterized by narrow spectral emission lines. Other bright nebulae, existing near cooler stars and not receiving the radiation necessary to make them self-luminous, reflect the starlight and are called reflection nebulae.