Viewing Planets or stars from a high altitude

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Discussion Overview

The discussion revolves around the visibility of planets and stars from high altitudes, particularly during daytime. Participants explore the conditions under which celestial bodies can be seen from space and the International Space Station (ISS), addressing factors like sunlight scattering and camera limitations.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants assert that planets and stars are not visible during the daytime due to sunlight scattering, while others challenge this by stating that Venus can be seen if one knows where to look.
  • One participant notes that the brightness of the Earth can overwhelm the visibility of stars and planets in photographs taken from the ISS during the day.
  • There is a suggestion that the sky becomes progressively darker at higher altitudes, potentially allowing stars to be visible from the ISS, but photography techniques must account for the differences in luminosity.
  • Another participant expresses a misconception about the visibility of stars from the ISS during daytime, indicating a need for clarification on this topic.
  • Concerns are raised about the limitations of human vision compared to cameras when observing bright celestial objects against a bright background.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the visibility of stars and planets from high altitudes during the day, with some asserting that only the brightest objects can be seen while others believe that visibility is possible under certain conditions. The discussion remains unresolved with multiple competing views.

Contextual Notes

Participants highlight the influence of sunlight scattering, camera exposure settings, and the brightness of the Earth on the visibility of celestial bodies, indicating that assumptions about visibility may vary based on these factors.

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?
 
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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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