Viewing Planets or stars from a high altitude

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Anand Sivaram
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TL;DR
Viewing Planets or stars at high altitude
We can not see planets or stars during the day time because of the scattering of the sunlight. But, in space, all planets and stars would be visible. Consider the situation that a rocket is going to space during the day time. At what altitude these stars or planets would become visible? On the contrary, consider an astronaut coming back from the ISS to the Earth during day time. Until what altitude he could see bright stars like Sirius or planet Venus?
 
on Phys.org
Anand Sivaram said:
We can not see planets or stars during the day time because of the scattering of the sunlight.

You can if you know where to look
I have seen Venus many times during the day

Anand Sivaram said:
Consider the situation that a rocket is going to space during the day time. At what altitude these stars or planets would become visible?

On the daylight side of the Earth, they won't be seen (except maybe Venus) for the same reason as on the ground ... the sun glare

Maybe you have not noticed the lack of stars in photos from the ISS and other spacecraft when in the daylight ... ?

Because you started with a flawed assumption, you need to reconsider your first statement
 
davenn said:
Maybe you have not noticed the lack of stars in photos from the ISS and other spacecraft when in the daylight ... ?
The Earth is very bright and will swamp dim images of stars and most planets unless the camera is mounted somewhere (outside, preferably) where there is no significant scattered light from a sunlit Earth.
The 'sky' gets progressively darker and darker as you go up and looks black from the ISS orbital height. Stars should look much the same as they do on a clear night on Earth. But if you try to take a photograph of the night sky with similar exposures to daylight Earth scenes, you won't see much. It's down to the massive differences in luminosity of objects in shot.
 
Anand Sivaram said:
I was under an impression that the Astronauts could see any star or planet from the ISS during their day time.
Very likely but I doubt that any but the brightest stars could be seen when they lie near the bright Earth. Our eyes are a lot better than cameras until we start to get cataracts - flare is a real s*d for us oldies. (We lack the right stuff I think.)
 
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