from earth, we can see stars. From the ISS live stream, we cannot see the stars. How come?

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I noticed when watching the live stream video from the ISS there were no stars visible, in the same way we see them from earth. The ISS was in a night zone of the earth. Does it have to do with light?

In: Earth Science
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Most of the time it is daytime on ISS. Even though the sky is not bright blue like on Earth but rather black the ISS itself and the Earth in the background is still lit up making it even brighter then even the brightest day on the surface. This means that all the cameras and indeed the crews vision is adjusted to daytime. This makes it impossible to see any stars in the footage. It is actually the same reason why we can not see stars from the surface of the Earth during daytime as well. The stars is still there in the sky and shines just as bright during the day as they do during the night. However the light from the Sun and all the secondary reflections from the sky and the ground lights up everything so that it is impossible to see the stars without specialized equipment.

The light from the stars is often too weak and dim to be easily picked up on camera, especially if there is something much brighter in the camera field. In order to just take a picture of the night sky it often requires a long exposure time. We can see the stars with our naked eyes because our eyes are much more sensitive than most cameras and are capable of fairly quick adjustments, allowing us to focus on the dim points of starlight.

We can’t see the stars because the sky is dark and taking good pictures of the sky requires some long exposure shot. This is also why when you randomly snap a picture of the sky you can’t always catch stars, even if you do see them.

When they do take [good enough pictures](https://eol.jsc.nasa.gov/DatabaseImages/ESC/small/ISS044/ISS044-E-45215.JPG), you can see a lot of stars.

It has to do with the cameras and with overall exposure/ISO. It would be worth your while to understand how a camera works to better understand this answer.

Essentially, a camera is not as complex as the human eye. And in order to see light from billions of light years away, we need to leave the shutter open for a long time and also bring up the sensitivity of the ISO sensor in the camera. This is how we get “galaxy images” from amateur photographers. Unfortunately, the video cameras on board the ISS are not as fine-tuned and thus do not receive the light information from the stars. The overpowering light source is coming from the sunlight bouncing off the planet and if the sensors on the cameras were turned up, the Earth would be blown out and we wouldn’t be able to see anything.

Our eyes, on the other hand, can process all of this together so we see it all. The astronauts on the ISS can see the stars.

We can only see the stars at night. There is no blue sky on the ISS because it’s above the atmosphere that makes it blue, but otherwise it’s still daylight.

They’re too dark for the low-quality camera to pick up.

Your eyes have no issues because eyes are *amazingly* good cameras. It cannot be stressed enough just how good they are. [Under ideal circumstances, we can even detect single photons.](https://www.nature.com/articles/ncomms12172)

It’s a big part of the reason why pictures of things never quite look as good as real life. You need an extremely expensive camera to get something even approaching the dynamic range and sensitivity of the human eyes. [Take such an expensive camera onto the ISS and you can have it film the stars just fine](https://www.youtube.com/results?search_query=ISS+night+footage+4K).