The Naked Scientists

The Naked Scientists Forum

Author Topic: Where Have All The Stars Gone ?  (Read 2547 times)

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Where Have All The Stars Gone ?
« on: 02/04/2009 02:38:58 »
I know I have seen the explanation to this before (ususally in the conspiracy theory threads) but can someone explain again why I can't see any stars in this picture ?


Or is the whole Space Shuttle/Space Station thing a hoax ?





 

Offline Karen W.

  • Moderator
  • Naked Science Forum GOD!
  • *****
  • Posts: 31653
  • Thanked: 5 times
  • "come fly with me"
    • View Profile
Where Have All The Stars Gone ?
« Reply #1 on: 02/04/2009 02:47:38 »
I never noticed that in pictures before!
 

Ethos

  • Guest
Where Have All The Stars Gone ?
« Reply #2 on: 02/04/2009 02:50:06 »
I believe the answer to this is; The time exposure needed to make the stars visable is not necessary when taking these pictures of the space station.
« Last Edit: 02/04/2009 02:55:09 by Ethos »
 

lyner

  • Guest
Where Have All The Stars Gone ?
« Reply #3 on: 02/04/2009 10:34:46 »
It may be easier to discuss if you imagine that the photo were taken with a simple digital camera. If the sensor used 8 bits, that would give 256 possible brightness levels. If you exposed the picture so that the brightest highlight was level 256 and the brightest star in the picture had a brightness of less than 1, it would not be displayed.
The range is actually much more than 1:256 in the scene in the picture so, even though film has a wider contrast range, the effect of flare (light being spread all over the picture from the brightest areas) means the stars will never show.
Let's face it. To take a picture of the stars from Earth, at night, you'd need a wide lens / long exposure which would be totally unsuitable for sunny holiday snaps.
No conspiracy!
 

The Naked Scientists Forum

Where Have All The Stars Gone ?
« Reply #3 on: 02/04/2009 10:34:46 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums