All Questions
Tagged with astronomy visible-light
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Is there a reason why in the astronomic pictures of galaxies and nebulosas there is so little green color?
From a quantum physics standpoint, why do astronomical images of galaxies and nebulae exhibit so little green color in their spectral composition?
When we look at the pictures of galaxies provided by ...
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What does the sky look like from the moon?
From pictures taken on the moon, it appears that there are no stars visible in the sky, but I do not know if this is an effect due to cameras.
What is the actual appearance of the sky on the moon?
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Why do sun emit light of different frequencies? [duplicate]
The sun emits white light, which is a mixture of light from all frequencies. Instead, it should have emitted a beam of light of the same frequency, as the source is the same?
So, can you please ...
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Why does the Moon - which is grey - appear white to us even at daytime?
The color of the Moon as viewed more closely, is grey. But when we see it in the sky it appears white to us. Why?
Although this question has some answers here: Why is the surface of the Moon white? (...
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How can photons be emitted from a star, travel millions/billions of years in a "straight line", and be seen by two adjacent observers?
If photons are emitted by a star and travel millions/billions of years in a "straight" line, they can be seen by adjacent observers. This makes it seem like there must be an uncountable ...
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Observed flux of a non-spherical object
I recently had an exercise for which I had to find the observed flux of an annulus (accretion disc of a black hole). With the assumption that the annulus behaves as a perfect black body, the provided ...
- 3,778
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Difference between Earth's surface area seen from ISS and the theoretical area if light refraction is neglected
What is the difference between Earth's surface area seen from ISS and the theoretical area if light refraction is neglected? I watched a video telling that it is not possible to know why a great ...
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Why does the light from stars / satellites tremble? [duplicate]
Clear Sky.
1 ---> Light from stars visible.
2 ---> Light from satellites visible.
3 ---> Light from airplanes (passing by) visible.
Apart from the change in color, the light from 1 and ...
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Why do we see only the sun as yellowish or orangish? Why not stars, because both of their light undergoes atmospheric refraction? [duplicate]
We see the colour of the sun as yellow to orangish on an average due to its light getting refracted due to the atmosphere. Then why do we see stars as white and not colourful, because light coming ...
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How much can we enlarge the picture of a distant galaxy by this method?
If reflection is used instead of refraction and if the curved mirror is highly reflective and cast the image of the galaxy in a obscure chember on a relatively distant screen how much the image can be ...
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Why is it so dark during a solar eclipse?
At a total solar eclipse the sun is barely covered, like right after sunset. So why is it much darker than right after sunset (which allows us to see the corona)?
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Is it possible for an undiscovered, large object of the solar system to occult a star on the sky?
Is it possible for an undiscovered, large object of the solar system to occult a star on the sky? Maybe trying to discover it by gravitational effects is hard but can astronomers obseve a occultation ...
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Why Earth is viewed crescent from moon when the Earth is experiencing total solar eclipse?
Suppose a person, let's say Neil, is on moon and Earth is experiencing a total solar eclipse so how should Neil perceive the Earth? This is also a question from KVPY (5/11/2017) question no. 22. as ...
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How precise must corner reflectors be to render satellite megaconstellations effectively invisible to astronomers?
With the emerging environmental concerns over light pollution from satellite megaconstellations, getting a quantitative estimate of the magnitudes of various approaches to minimizing the pollution ...
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How bright would the surface of each planet be?
At night when there is no moon in the sky, it is dark, you can not see your surroundings. If I were to stand on Pluto, could I see my surroundings? Would being on pluto at day be like night on earth ...
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