why don’t we see stars from the lunar surface?

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If we can see the Milky Way on earth when there’s dark skies, why can’t we see it from the moon? All the videos and photos I’ve seen, it’s just black with no stars.

In: Physics
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https://www.planetary.org/blogs/emily-lakdawalla/2019/why-are-there-no-stars.html

Basically, it’s because the stars are too faint to show up in the photos because of the kinds of cameras being used.

All the videos and photos you’ve seen were taken during the lunar daytime, when the lunar surface is sitting in direct sunlight—meaning all the camera equipment is adjusted to daylight settings. There may not be an atmosphere to glow blue and drown out the stars, but the stars are still impossibly faint compared to the ground in direct sunlight.

The surface of the moon is *very* reflective. It’s a fine, nearly white, dust. It reflects so much sunlight that astronauts have to wear heavily tinted visors to see.

A camera captures light to make a picture. If it takes in too much light, the picture looks over-bright and washed out. To prevent that you set exposure time. A shorter exposure allows less light in, and prevents washing out of the image, but also doesn’t capture relatively dim things.

On the moon the surface is so bright that any exposure long enough to capture the relatively dim stars would be completely washed out, and you wouldn’t be able to see anything of the surface except a white blur.

Basically those pictures are taken during the day – otherwise it would be too dark. The lunar surface outshines the stars.

There are two main reasons.

First is the same reason we don’t see stars during the day on earth, the sun is so much brighter than the rest of the stars that it is hard to see them.

Second is how cameras work they take in as much light as you tell them to, if you were able to see the stars in say the moon landings, you would not be able to see the people at all. It would be to bright.

> If we can see the Milky Way on earth when there’s dark skies, why can’t we see it from the moon?

You absolutely can see stars and the Milky Way on the Moon when there’s dark skies.

You just haven’t seen dark skies on the Moon before. All the Apollo landings occurred during the lunar day, when the sun was out. They needed to land in the daytime so they could see the surface when they were landing.

You can’t see them in the picture, because the picture has been taken in the day on the moon, so you can’t really see the stars because they are too dimm for the camera

But if you were there in person, since there is no atmosphere you could adjust your eyes to the darkness and see the stars, if they had used different camera settings they also could have shown the stars, but the astronauts and the moon would have been overexposed and washed out

You forget that they’re taken during the lunar day, because the sky is obviously dark with lack of atmosphere, that makes total sense now!

If you take a picture of a person with the bright sky to their backs, you will either be able to see the person with a fainter sky, or a bright sky with a very dark looking person. It has to do with what the camera is trying to show in “normal” brightness.

Pictures taken from the lunar surface are adjusted to show the very bright ground. By adjusting to make the very bright surface “normal” looking, it has to make the entire image darker, including the stars.

There is no atmosphere to scatter light on the moon, so if you were actually standing there yourself you would be able to see the stars if you looked up and didn’t have the lunar surface taking up a large part of your vision to drown out the stars.

The astronauts on the moon said they could see stars, so it isn’t that they were invisible, they just didn’t show up in pictures. On Earth you don’t see many stars in daytime because the atmosphere creates a sort of “lampshade” affect, and the atmosphere being lit up means most stars are blocked out, but on the Moon with no air, the stars can punch through.

This eye/picture difference is down to the difference between your eyes and a camera. Your eyes send a message to your brain about 20-30 times/second, and your brain does a sort of photoshop process to combine all the information into what you “see”.

A camera can only focus on one thing at a time, however. If you are in broad daylight and take a picture, the camera shows the image fine. If you are in the dark, it might turn on a flash or lengthen the shutter time. But if you are in the dark and cover the flash, the camera has no idea, it takes the picture assuming there is enough light– and you get a dark image.

But unlike a camera, your eyes do dark/light images several times/second and combine them together without you being conscious of it. In order to do that with a camera, you would have to manually take a picture at multiple settings and photoshop them together after.

For the cameras they took to the Moon, they were all pre-set to take pictures of full sun. They were not open long enough for the fainter stars to show up. If they had taken pictures of the stars, the Moon and astronauts would have just been whited out from too much light in the foreground.

Some more/better info here:

[https://www.planetary.org/blogs/emily-lakdawalla/2019/why-are-there-no-stars.html](https://www.planetary.org/blogs/emily-lakdawalla/2019/why-are-there-no-stars.html)

[https://www.space.com/first-to-the-moon-apollo-8-movie.html](https://www.space.com/first-to-the-moon-apollo-8-movie.html)

Go outside at night, stand under a porchlight, and take a selfie with the clear night sky in the background. The phone will adjust to the bright light on your face and not the dark skies, making the stars invisible.

That’s what happened on the moon, the cameras were there to photography the surface, not the sky. If they had been adjusted to capture the stars, the surface would have been hopelessly washed out.