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Moreno

Is Earth's atmosphere transparent one way only?

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We cannot see the stars in midday because atmosphere is not transparent to our vision. How then the satellites make the pictures of Earth surface which is perfectly visible regardless the atmosphere?

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3 minutes ago, Moreno said:

We cannot see the stars in midday because atmosphere is not transparent to our vision. How then the satellites make the pictures of Earth surface which is perfectly visible regardless the atmosphere?

That's a fairy tale. We cannot see the stars in daytime, simply and logically because the brilliant light from the star/Sun, drowns out the rather dim light from the stars.

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Posted (edited)

It's not about transparency, it's about the light from stars being dim and being washed-out by daylight. Your eyes can't cope with bright light from your surroundings, and see the stars.

Same reason photos taken on the Moon generally don't show stars - even though there's practically no atmosphere there.

A satellite camera will be arranged so that direct sunlight doesn't cause the same issue.

There's no reason for simple air to be one-way transparent.

 

edit: at night, where do you think the atmosphere goes to make stars visible?

Edited by pzkpfw

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10 minutes ago, Moreno said:

We cannot see the stars in midday because atmosphere is not transparent to our vision. 

We can usually see one star at this time (the Sun). We can sometimes see the Moon. 

In the morning or evening you can often see Venus as well. 

So it is obviously not a problem with transparency. 

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Posted (edited)

Looking at Earth from space, the photons reflecting off the land and sea back at the camera in space overwhelm the effect of the Rayleigh scattering of photons  in the atmosphere that normally makes the sky/atmosphere look blue.   We can also see the effect in the blue seas. When we look out towards space from Earth in the day, the Rayleigh scattering within the atmosphere dominates over the darkness and light of the more distant stars and thus looks blue. Contrast plays a part too, as already mentioned.

Edited by StringJunky

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30 minutes ago, StringJunky said:

Looking at Earth from space, the photons reflecting off the land and sea back at the camera in space overwhelm the effect of the Rayleigh scattering of photons  in the atmosphere that normally makes the sky/atmosphere look blue.  

What about water vapors? Don't they suppose to scatter light strong enough to prevent good visibility?

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38 minutes ago, Moreno said:

What about water vapors? Don't they suppose to scatter light strong enough to prevent good visibility?

It seems water droplets are not selective for just scattering blue photons like the smaller gas molecules and will scatter all wavelengths. Yeah, they probably contribute to blocking. I'm sure swansont can elaborate on this.

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1 hour ago, Moreno said:

What about water vapors? Don't they suppose to scatter light strong enough to prevent good visibility?

You've heard of clouds?

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