Why are emission spectra of stars rarely shown?

  • I
  • Thread starter pkc111
  • Start date
  • #1
192
22
Summary:
e.g I dont think I ve ever seen one of our Sun.
According to this link you just have to anlayse the light that isnt coming from a place on the star that has a light the source directly behind it e.g wouldn't looking at light from the outer edge of star give you an emission spectrum?

http://www.thestargarden.co.uk/Spectral-lines.html
 

Answers and Replies

  • #3
192
22
Yes thank you so much phys guy..that makes perfect sense. Im still not quite sure why they have to wait for an eclipse, I would have thought they could just sample light coming from the outer edge of the Sun, but anyways Im sure they have their reasons ;)
 
  • #4
Orodruin
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
Gold Member
17,247
7,068
Yes thank you so much phys guy..that makes perfect sense. Im still not quite sure why they have to wait for an eclipse, I would have thought they could just sample light coming from the outer edge of the Sun, but anyways Im sure they have their reasons ;)
If you do not wait for an eclipse you will be completely blinded by the thermal emission spectrum from the Sun.
 
  • #5
192
22
yes I read that, so Im wondering why you wouldnt use a camera (viewed on a monitor) to just select from the outer light ring?
 
  • #6
sophiecentaur
Science Advisor
Gold Member
2020 Award
26,162
5,372
yes I read that, so Im wondering why you wouldnt use a camera (viewed on a monitor) to just select from the outer light ring?
Should be a doddle? No. The brightness of the Sun's disc is so great that there is far too much 'spillage' of light on its path through the atmosphere to get the detail that a total eclipse can give us.
It is possible to get an imperfect image of the corona with a terrestrial coronagraph telescope. This puts a disc over the intermediate image inside the scope which covers the Sun's main part. But it only takes you so far. You can't get away from the effects of the atmosphere. Hubble does some solar measurements by this method ( a different camera from the deep space one!!!) An alternative would be to use a large disc at some distance in front of a space telescope to produce your own 'eclipse' but it all needs to be out in space and carefully guided.
 
  • Informative
Likes Klystron and FactChecker

Related Threads on Why are emission spectra of stars rarely shown?

  • Last Post
Replies
9
Views
5K
  • Last Post
Replies
10
Views
2K
  • Last Post
Replies
3
Views
1K
Replies
3
Views
2K
  • Last Post
Replies
3
Views
1K
  • Last Post
Replies
3
Views
2K
Replies
5
Views
3K
Replies
3
Views
1K
Replies
6
Views
1K
Top