Share this entry

Share this page

planetary nebula

Line breaks: planet|ary neb¦ula

Definition of planetary nebula in English:

noun

Astronomy
A ring-shaped nebula formed by an expanding shell of gas round an ageing star.
Example sentences
  • Astronomers call such an object a planetary nebula, because its round shape resembles that of a planet when viewed with a small telescope.
  • The Boomerang Nebula is a young planetary nebula and the coldest object found in the Universe so far.
  • Until recently, it was thought that shells around planetary nebulae were a rare phenomenon.

Definition of planetary nebula in:

Share this entry

Share this page

 

What do you find interesting about this word or phrase?

Comments that don't adhere to our Community Guidelines may be moderated or removed.

Get more from Oxford Dictionaries

Subscribe to remove ads and access premium resources

Word of the day terpsichorean
Pronunciation: ˌtərpsikəˈrēən
adjective
of or relating to dancing