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We've all seen tons of images taken by astronauts and spacecraft, but many times they are artificially colored, include invisible light spectrums, or have a lot of contrast.

Apollo 11 return

I would imagine, without the atmosphere and artificial light from civilization, that the stars and the sun would be even more brilliant from space. But in picture from the ISS or spacecraft the background often looks completely black. Of course, cameras can't capture an image the way a human eye would.

So my question is are there any accounts from astronauts or experts on what space actually looks like from space?

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    $\begingroup$ Try this some time: During a clear night, go outside (in an area without significant light pollution) and wait until your eyes have adapted to the darkness. If you look at the sky, you will see a large number of stars. Now, as quickly as possible, go indoors into a brightly lit room, open a window (to prevent reflections in the glass from interfering with the experience) and look at that same sky. How many stars do you see now? $\endgroup$ – a CVn Jul 21 '16 at 9:00
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To answer your specific question "are there any accounts from astronauts or experts on what space actually looks like from space?", yes, there are many. Every astronaut memoir I have read has always addressed this.

Here's an example from Mike Collins' book Liftoff

My God, the stars are everywhere, even below me. They are somewhat brighter than on earth, but the main difference is that they don't twinkle.

From Jerry Ross's book Spacewalker

To see stars at night we had to turn down all the orbiter's interior lights to make it dark and eliminate the reflections in the windows. Then we could view so many more stars than one could ever gaze at from Earth, and during a single orbit we could see both Northern and Southern Hemisphere stars.

And this

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What space looks like in space depends on what is around you that might scatter light. The human eye is very adaptable to varying light conditions, in low light conditions the iris dilates to let in as much light as possible, in high light conditions it contracts to restrict light to give the retina a consistent amount of light and to protect it from damage from too much light.

On the Earth you cannot see the stars in the day because the atmosphere scatters light from the sun. The stars are still there of course but they are drowned out by the other light. Also, your pupil is too small to give the sensitivity to low light emitters. On the earth at night how many stars you see depends on the condition of the atmosphere and the amount of scattered light there is, which is why modern observatories are built in high altitudes far from any light pollution.

In space what you see is determined by what is around you and what is scattering light in your direction. The surface of the moon is very bright in sunlight, so if you are standing on the surface looking at the moon your pupil will contract and you will see fewer stars.

If you are floating in space no-where near any light scattering source, with the sun out of your field of view then your eyes would dilate out and be at their maximum sensitivity (after 20 minutes - it takes time for your night vision to kick in fully) what you would see is the deepest, deepest black punctuated by the unwavering pinpricks of stars (no twinkling as there's no atmosphere), and a bright glow from the milky way. It wouldn't be that different from looking up at the sky from the palomar observatory (or any other high point) on a clear and moonless night - at palomar you wouldn't be looking through a layer of glass or plastic designed to keep you from asphyxiating, but the view in space would be even more spectacular.

The moon has no atmosphere to speak of to scatter light, so if you lie on the surface of the moon facing up, and the sun and earth are not in your field of view, it would be the same thing as if you were in open space. As soon as the earth, moon or sun came into your view the light will cause your eye to contract and you'd see less stars.

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Like this: Stars from spacestation Sometimes pictures from the Moon show dark sky with no lights because the Earth is very bright and drowns out the much fainter stars. A picture taken with short exposure just does not collect enough light to show those faint objects.

Long exposure, time-lapse kind of shots are much closer to what a human would see.

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We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.

  • $\begingroup$ This really needs context though - how the human eye has adapted to the lighting conditions determines how many stars we see. $\endgroup$ – kim holder Jul 20 '16 at 19:26
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    $\begingroup$ Also, the human eye is basically a logarithmic detector, whereas digital cameras and film cameras are not. $\endgroup$ – Phiteros Jul 20 '16 at 20:31
  • $\begingroup$ "pictures from the Moon show dark sky with no lights because the Earth is very bright and drowns out the much fainter stars." Well, yes and no. Taking the Apollo photographs as an example, the astronauts exposed those images for proper exposure of the lunar surface. The resultant exposure settings were far too low to allow stars to be exposed significantly on the film. Without air, there is no light diffraction in the sky; with ideal film and lenses, you could get a photo of the stars surrounding Earth by exposing for the stars where the Earth would show as just a white, overexposed circle. $\endgroup$ – a CVn Jul 21 '16 at 9:03
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    $\begingroup$ This answer needs more. A video alone isn't proof of what humans see. $\endgroup$ – called2voyage Jul 21 '16 at 13:40

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