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ElliotSmith
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- How much brighter is the sun from space than it is when viewed from Earth?
How much brighter is the sun when seen from space than it is when viewed from Earth?
It's difficult to know exactly what you mean by your question but, if you are just concerned with visible light then we can say that the difference will not be great. (Ball park figure) There is a so called window in the atmosphere which let's the optical (visible) part of the EM spectrum through with very little attenuation. There's no surprise that we evolved with the ability to detect those particular wavelengths because there is more energy around for our eyes to detect. Some wavelengths are absorbed very strongly and there would be very little to 'see', even if we had appropriate sensors. In the visible region the light is hardly absorbed at all but it is scattered.ElliotSmith said:Summary:: How much brighter is the sun from space than it is when viewed from Earth?
How much brighter is the sun when seen from space than it is when viewed from Earth?
because, without all that scattered light (i.e. in space), the shadows would have Zero brightness and all the light would fall only on the ground outside the shadows. The effect on the ground outside shadows is a good representation of the effect on 'how bright' the Sun would look (but DON'T LOOK!) up there and down here.hmmm27 said:30% give or take.
DaveC426913 said:Catching a glimpse of the Sun when your eyes are fully dilated, it could appear - at least in theory - as much as 16,000 times brighter:
"..., most estimate that our eyes can see anywhere from 10-14 f-stops of dynamic range.."
https://www.cambridgeincolour.com/tutorials/cameras-vs-human-eye.htm
There is also an 'automatic gain control' - otherwise known as Dark Adaptation. The large figure quoted by @Drakkith is 'of interest' and it also applies to turning on the bedroom light in the middle of the night. We would assume that the OP implied not looking at the Sun at night. (Haha)Drakkith said:not even close to 16,000x
I read the "link" from @DaveC426913 that says 10-14 f stops of dynamic range is what the human can see. Perhaps the terminology they use is poor and misleading. I think @Drakkith has the f-stop much more accurately quantified.Drakkith said:I'm not sure how that works. Just going off of pupil size, the intensity of light in the image is directly proportional to the unobstructed area of the pupil. Since the pupil varies from roughly 2-7 mm in diameter, the difference in area is only about 12x, which is not even close to 16,000x. Can you enlighten me here, Dave?
Yeah. In retrospect I may have conflated two things.Drakkith said:I'm not sure how that works. Just going off of pupil size, the intensity of light in the image is directly proportional to the unobstructed area of the pupil. Since the pupil varies from roughly 2-7 mm in diameter, the difference in area is only about 12x, which is not even close to 16,000x. Can you enlighten me here, Dave?
DaveC426913 said:So yeah, the sun may appear about 12x brighter if you look at it with your night vision engaged.
(Though frankly, that seems quite low. If you've ever had drops put in at the Optometrist, you know that it is impossible to open your eyes more than a slit in broad daylight - never mind looking at the sun!)
The Sun appears about 100 times brighter when viewed from space compared to on Earth. This is because there is no atmosphere in space to scatter and absorb sunlight, making it appear more intense.
No, the brightness of the Sun remains the same regardless of where it is viewed from in space. However, factors such as the angle at which it is viewed and any objects in the foreground may affect its perceived brightness.
Yes, the distance from the Sun does affect its brightness when viewed from space. The closer a spacecraft or satellite is to the Sun, the brighter it will appear. This is because the intensity of sunlight decreases with distance.
The Sun is one of the brightest stars when viewed from space, but there are many other stars that appear brighter. This is because the Sun is relatively close to Earth, while other stars are much farther away.
Yes, the brightness of the Sun can be harmful when viewed from space without proper protection. The intense radiation and UV rays emitted by the Sun can damage the eyes and skin. Astronauts and spacecrafts are equipped with special filters and shields to protect against this brightness.