× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
d
4
N
3
3
R
3
k
3
o
3
Z
3
j
3
s
3
d
3
J
3
1
3
Home Q & A Board Science-Related Homework Help Physics
New Topic  
bugg bugg
wrote...
Posts: 52
Rep: 0 0
11 years ago
A) Molecules such as NH3 and CH4, which contribute to giant molecular clouds
B) UV light that photoionizes hydrogen. This hydrogen, upon recombination, produces the red balmer light by which we see interstellar emissions nebulae.
C) Rotational motion from the original star, which serves to concentrate interstellar matter into new stars and planetary systems.
D) The nuclei of moderately heavy elements, major components of planets such as our own

Sources for verification if possible please...
Read 473 times
1 Reply

Related Topics

Replies
wrote...
#1
11 years ago Edited: 11 years ago, bio_man
Planetary nebulae play a crucial role in the chemical evolution of the galaxy, returning material to the interstellar medium that has been enriched in heavy elements and other products of nucleosynthesis (such as carbon, nitrogen, oxygen and calcium). In more distant galaxies, planetary nebulae may be the only objects that can be resolved to yield useful information about chemical abundances.
New Topic      
Quick Reply
Explore
Post your homework questions and get free online help from our incredible volunteers
  1462 People Browsing
Start New Topic Take the Tour CoursesNew Study Tools Topics Trending Browse by Textbook
Live Chat
Related Images
  
 834
  
 570
  
 1193
Your Opinion
Which of the following is the best resource to supplement your studies:
Votes: 365
Previous poll results: Do you believe in global warming?