Top Posters
Since Sunday
p
4
h
4
c
4
d
3
3
c
3
t
3
u
3
A
3
B
3
j
3
s
3
Home Q & A Board Science-Related Homework Help Physics
New Topic  
killian killian
wrote...
Go to Answer
Silver Member
Posts: 6024
Rep: 33 0
10 years ago
How do we determine the amount of dark matter in elliptical galaxies?
A) We measure the orbital velocities of star-forming gas clouds in the outer portion of the galaxy.
B) We measure the broadening of the galaxy's absorption lines to infer the speeds of stars at different distances from the galactic center.
C) We count the number of stars in the galaxy. Combining this with the galaxy's volume, we can calculate the galaxy's density.
D) We search for dark lanes of dust and black holes within the galaxy.
E) We measure how fast the galaxy rotates as a whole.
Read 399 times
2 Replies
Smiling Face with Open Mouth
Replies
Answer accepted by topic starter
padrepadre
wrote...
#1
Staff Member
Educator
Top Poster
Posts: 21610
Rep: 4541 17
10 years ago
Sign in or Sign up in seconds to unlock everything for free
1
Mastering in Nutritional Biology
Tralalalala Slight Smile

Related Topics

killian Author
wrote...
#2
Silver Member
10 years ago
Thank you sir
Smiling Face with Open Mouth
New Topic      
Quick Reply
Explore
Post your homework questions and get free online help from our incredible volunteers
  1230 People Browsing
Start New Topic Take the Tour CoursesNew Study Tools Topics Trending Browse by Textbook
Related Images
  
 568
  
 157
  
 617
Your Opinion
Which 'study break' activity do you find most distracting?
Votes: 820
Previous poll results: Which country would you like to visit for its food?