Why can’t you see stars when you go above Earth’s atmosphere?

I have never been in space. At least any more than I am always in space because it is something that we, and the atmosphere, are all inside of.

Space, I am in you.

But getting back to the point. The cheapest, retro web designed section of the NASA website, gives us our answer.

The answer is that the whole thing is a myth, perpetuated by the weirdnesses of photography., and then presumably perpetuated by people trying to be clever.

With the human eye, much as you’d expect, stars are much brighter when viewed from outside of the Earth’s atmosphere. The twinkling effect disappears as well (though presumably, the illusion where they appear to be moving is still in effect, that’s just a thing the brain does with dots of light in complete darkness, without other points of reference). Basically, the atmosphere of the Earth does fuzz things a little, and complicated adjustments (or a law of averages ‘luck’ approach) have to be used to get clear readings on where faint stars and other objects are.

Out in space, everything is crystal, because there is no atmosphere to get in the way (and little in the way of light pollution), so everything is clearer and brighter, and the stars are, apparently beautiful.

So why do we not seem them in photos? Why does that lead loads of other people to believe that to accurately represent space, it just needs a black void? (I noticed this recently for the first time when one of my web comics had a space scene, and in the text below the artist apologised for including stars when he knew it wasn’t right. This was the first time I’d heard of this phenomena and it sounded unlikely, but who am I to argue with web comic artists? The answer is: I am fueled by google searches and NASA.)

Anyway. I can’t explain this any better than the link I’ve already given you, but basically, whenever you see photos in space, they are normally of something much nearer and brighter than stars. We normally take pictures of things with some kind of interest, like the Sun, or the Moon, or the Earth, or the astronaut, or the shuttle, or a space station, or whatever.

Those things are so much closer than the stars, and therefore so much brighter, that as the camera gets the right exposure to take them, it drops the stars in the background out of the picture.

We don’t see the stars because the other things are brighter. The human eye has no such exposure problems, it’s really clever like that.

So it’s just a trick of the light, essentially. Cameras aren’t accurate readers of information.

For the web comic artiste, and anyone else wanting to represent space. Be aware to only paint it black if you are trying to suggest that your point of view is mechanical.

And it’s handy. Because I reckon space would freak me out if it was any emptier.

Illustration by Helen

And re-illustrated under instruction from Alex, again, by Helen:

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About Alabaster Crippens

Learner. Guesser. Thinker and Stinker.
This entry was posted in Illustrations by Helen, Questions by Hannah. Bookmark the permalink.

13 Responses to Why can’t you see stars when you go above Earth’s atmosphere?

  1. Alistair says:

    Well Neil Armstrong happens to disagree with NASA. When he described his Moon mission experience, he said that stars are *not visible* from space: http://www.youtube.com/watch?v=PtdcdxvNI1o

    I also find absolutely no “visible light” camera pictures of stars on the NASA website.

    Wilhelm Reich says that light is not irradiated from the sun as light, but rays from the sun stimulate or trigger the luminosity of the earth’s atmosphere. http://goo.gl/7Snx8

    Eric Dollard says the same as Reich and Armstrong, and also that stars are invisibile because stars are electric not nuclear: https://www.youtube.com/watch?v=PWvLO8iadfs

    Interesting huh?

    This color theory video contains some smoke–box experiments that make it easier to think about: http://www.youtube.com/watch?v=GiCI1HVLgBI

    • Hilary says:

      You’re right. The atmosphere actually does a great deal for our eyes in seeing stars from space. Light interferes with gas clouds (such as our atmosphere) allowing them to become visible because when photons strike matter, they also give off energy. Molecular clouds in which stars form are so dense, that we may look up with our telescopes and see what people have perpetuated as a “void.” Interstellar reddening also occurs around the clouds. But yes, it’s a little more difficult to see stars when out in space as Neil says. I believe in Chris Hadfield’s book, he also mentions it.

  2. Alistair says:

    Also… if you find a “visible light” photo of the sun taken from space, let me know. I’m yet to find one.

    • Gabby says:

      that only means that Neil was a liar and never was on the moon, and that you’re a fool for believing man landed there. The eye can see stars no matter where it is. Eyes are better than cameras. The moon landing was a giant hoax. Wake up……

      • F1LT3R says:

        Whether Neil went to the moon or not – does not relate to the visibility of stars from space. Even if the moon landing was a hoax (I think it’s pretty clear *it was*), it a) doesn’t mean Neil never went into space and b) doesn’t mean that he was unqualified to speak on the matter of star visibility from sys linear space.

        Also, for you to say that the eyes can see stars no matter where you are is quite presumptuous. In a city with bright lights, in a black hole, with a plastic bag over your head, with your eyes closed: and possibly between earth and the moon too. You just can’t know beyond reasonable doubt until you have some evidence. Therefore I think you are being a little unreasonable. :P

  3. Keshia says:

    Thank-you! Though, would this be said thee exact same for video taking?

    • Presumably? Don’t know much about the difference between exposure times and what not in film cameras. But one assumes they work in a similar enough way to regular cameras to mean that the same problems would occur. (Sorry that’s not the most helpful answer. I’m ill informed enough in the first place.)

    • Steve says:

      The short answer is yes, even for a $30,000 video camera. Capturing images of stars would require over exposing the moon substantially. The very best modern video cameras can have a dynamic range of slightly more than 15 stops (each stop is a doubling of exposure). That means the brightest white in the frame could reflect 32,768 times as much light as the darkest black.

      The maximum apparent magnitude of the full moon (as viewed from Earth) can be as high as -12.9. Venus (the brightest planet, when it’s on the far side of the sun) has an apparent magnitude of -4.9. Sirius, the brightest star, has an apparent magnitude of -1.5. One order of magnitude is a change of 2.5, so the 8 orders of magnitude between Venus and the moon is comparable to about 10.5 stops. The 11.4 orders of magnitude between Sirius and the full moon is comparable to the 15 stop range of the best video cameras. That means that in a video camera image containing both Sirius and the full moon, the moon would be the brightest white and Sirius would be the darkest black. Being the darkest black, Sirius would not be visible in the resulting image. Obviously, all of the stars that are less bright would also not be visible.

      • F1LT3R says:

        This is good info. How would the camera respond if you just shot straight into space with cirus as the brightest object, no moon, earth, etc? (I’m assuming if you pointed the camera that way you would expect to see lots of stars. But I’m not sure I know about fstops or the magnitude of stars from space to really call it.)

        The real ingesting test would be… same camera setup in space as on earth, point to the same star, see which photo comes out brighter. I’m guessing from the visible light pictures I’ve seen of space (:cough:), that the stars are more visible from Earth; as Hillary suggests above.

  4. Ngawa Sherab says:

    I didn’t get what you guys mean. Did you say we can not see the stars from above atomosphere? If so, why not? Then, could we see the moon and sun from there? If so, How could that be?

    • As I say in the article, my understanding from a very lazy google (but at least a response from NASA), is that there is a myth that stars can’t be seen in space. This is mostly related to problems doing photography in space. At least according to my lazy google.

      Alistair, above, has give a load of links to much more detailed information, that possibly refutes what I’ve said it my article. It appears to be a pretty complicated, at the very least.

      • F1LT3R says:

        The thing with exposure though… if you focused *only* on the stars (no moon, earth or craft in the shot), surely by 2013 we would see some un-edited pictures of stars taken from space with a “Visible Light Camera”. But I can’t find any on NASAs web site. Having spent a lot of time tweaking the cutoff filter on all manor of NASA photos (public and military), I am shocked by what seems like a gaping hole in either our understanding of light or our body of evidence.

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