3 ms·

There's really just one pair of coincidences: the wavelength of light most able to pass through water is that emitted by our sun. All the other statements are e

There's really just one pair of coincidences: the wavelength of light most able to pass through water is that emitted by our sun. All the other statements are effected by that. And if the sun emitted another wavelength of light, perhaps another stable liquid would have emerged as the building block for life. I think what this really infers is that life on other planets could look more different from ours than we'd ever expect.

bweitzman 12y ago
I was thinking the exact same thing. I would add that there is one more coincidence which is that the Earth is covered in water.
- bjt 12y ago
  One more coincidence: Unlike most substances, solid water (ice) floats rather than sinking. If this were not true, many bodies of water would be solid through most of their depth.
dghughes 12y ago
My take on it is the opposite view it seems life on other planets living in liquid water would develop vision to see in the middle of the colour spectrum since it passes through water the best, the same as on earth. Life would need to have eyes adapted to the same frequency due to the properties of liquid water. If an alien planet with liquid water had a different class of star the light from it may not emit the same amount of the frequency of light to make through water compared to earth but to the life on that planet it would be normal. I think water is the key not so much the sun since life would need liquid water to exist and the light needed whether abundant or not could only be in the frequency alien eyes could use the best which would be the same as life on earth. The biggest factor in life being different on an alien plant I think would be due to gravity and atmosphere; pressure and oxygen level.
sliverstorm 12y ago
What about the bit about, UV & higher is too destructive to organic molecules for photosynthesis, while IR & lower is a very weak source of energy? That statement isn't just about the particular chlorophyll molecules that evolved on earth.
guard-of-terra 12y ago
Most stars produce light that can pass thru water. Give or take two thousand kelvins won't make much difference. However, that visible spectrum of stars corresponds to a band where atoms can capture/emit photons does seem like a coincidence to me. That's a cosmogonical coincidence however.

bweitzman 12y ago

I was thinking the exact same thing. I would add that there is one more coincidence which is that the Earth is covered in water.

bjt 12y ago
One more coincidence: Unlike most substances, solid water (ice) floats rather than sinking. If this were not true, many bodies of water would be solid through most of their depth.

dghughes 12y ago

My take on it is the opposite view it seems life on other planets living in liquid water would develop vision to see in the middle of the colour spectrum since it passes through water the best, the same as on earth. Life would need to have eyes adapted to the same frequency due to the properties of liquid water. If an alien planet with liquid water had a different class of star the light from it may not emit the same amount of the frequency of light to make through water compared to earth but to the life on that planet it would be normal. I think water is the key not so much the sun since life would need liquid water to exist and the light needed whether abundant or not could only be in the frequency alien eyes could use the best which would be the same as life on earth. The biggest factor in life being different on an alien plant I think would be due to gravity and atmosphere; pressure and oxygen level.

sliverstorm 12y ago

What about the bit about, UV & higher is too destructive to organic molecules for photosynthesis, while IR & lower is a very weak source of energy? That statement isn't just about the particular chlorophyll molecules that evolved on earth.

guard-of-terra 12y ago

Most stars produce light that can pass thru water. Give or take two thousand kelvins won't make much difference. However, that visible spectrum of stars corresponds to a band where atoms can capture/emit photons does seem like a coincidence to me. That's a cosmogonical coincidence however.