Go back
Why is the moon red in an eclipse?

Why is the moon red in an eclipse?

General

Vote Up
Vote Down

Asked this question in the thread titled Eclipse. Can anyone explain the science?

1 edit
Vote Up
Vote Down

Originally posted by Policestate
Asked this question in the thread titled Eclipse. Can anyone explain the science?
Ask nordlys she's bound to know!

Vote Up
Vote Down

Originally posted by Policestate
Asked this question in the thread titled Eclipse. Can anyone explain the science?
Before the eclipse is total, the last rays from the sun reaching the moon are refracted (bent) as they move through earth's atmosphere. The result is a reddish hue on the moon's surface as seen from here.

Vote Up
Vote Down

Originally posted by Policestate
Asked this question in the thread titled Eclipse. Can anyone explain the science?
Essentially when there is a lunar eclipse no light from the sun reaches the moon directly because the earth is blocking it, so the light that refracts around the earth's atmosphere is only part that gets to the moon.
I would surmise that this changes the wavelength or only allows light of certain wavelength to get through.

Vote Up
Vote Down

Originally posted by Bad wolf
Essentially when there is a lunar eclipse no light from the sun reaches the moon directly because the earth is blocking it, so the light that refracts around the earth's atmosphere is only part that gets to the moon.
I would surmise that this changes the wavelength or only allows light of certain wavelength to get through.
Yes I seem to remember that light towards the red end of the spectrum refracts more, due to its longer wavelength.
Thanks people

Vote Up
Vote Down

Originally posted by Policestate
Yes I seem to remember that light towards the red end of the spectrum refracts more, due to its longer wavelength.
Thanks people
Earth's atmosphere filters out most of the blue light.. what reaches the moon is the red light that remains. Dust and clouds in the Earth's atmosphere also are factors.

Vote Up
Vote Down

Originally posted by HandyAndy
Earth's atmosphere filters out most of the blue light.. what reaches the moon is the red light that remains. Dust and clouds in the Earth's atmosphere also are factors.
And the light we are seeing has been 'double filtered' for that special red eclipse effect. Once on the way to the moon from the sun, and again on the way to our eyes.
Nice effect.

Vote Up
Vote Down

Originally posted by Policestate
Asked this question in the thread titled Eclipse. Can anyone explain the science?
http://en.wikipedia.org/wiki/Rayleigh_scattering

Vote Up
Vote Down

Originally posted by Policestate
Yes I seem to remember that light towards the red end of the spectrum refracts more, due to its longer wavelength.
Thanks people
My understanding was that it's the opposite. I thought blue light gets refracted more.

Vote Up
Vote Down

Originally posted by Policestate
Asked this question in the thread titled Eclipse. Can anyone explain the science?
This when the sun comes between the Earth and the moon blocking it out.

P-

Vote Up
Vote Down

you all have it all wrong ( what else would you expect from pinhead chess players )...the moon is red during an eclipse because it is naked and it is blushing ( god, you have to explain everything to these cretins )...

Vote Up
Vote Down

Originally posted by reinfeld
you all have it all wrong ( what else would you expect from pinhead chess players )...the moon is red during an eclipse because it is naked and it is blushing ( god, you have to explain everything to these cretins )...
Thank you Charlie Brown.

Vote Up
Vote Down

Originally posted by Bad wolf
Essentially when there is a lunar eclipse no light from the sun reaches the moon directly because the earth is blocking it, so the light that refracts around the earth's atmosphere is only part that gets to the moon.
I would surmise that this changes the wavelength or only allows light of certain wavelength to get through.
And, vice versily speaking, if the earth did not have an atmosphere, during the same lunar eclipse, the moon would be totally dark since none of the light normally refracted by the thick earth atmosphere would ever get to the moon, it would be totally black for a few hours.

Vote Up
Vote Down

Originally posted by orangutan
And the light we are seeing has been 'double filtered' for that special red eclipse effect. Once on the way to the moon from the sun, and again on the way to our eyes.
Nice effect.
the more recently a major volccanic eruption has happened the more red the moon, suggesting that increased dust in the stratosphere increases the filtration of blue light. There haven't been any major volcanos go off recently, so the moon was more a orange than a deep red.

1 edit
Vote Up
Vote Down

Originally posted by Policestate
Asked this question in the thread titled Eclipse. Can anyone explain the science?
You shouldn't be looking at the moon during an eclipse, it's bad for your eyes.