Let There Be Light(seedmagazine.com)

13 pointsby cluiggivor 17 Jahren4 comments

http://seedmagazine.com/content/article/let_there_be_light/

1 comments

Can you see green on the earth from space from the plant life? If so I wonder if we could actually detect vegetation on these planets?

jerfvor 17 Jahren

You could also just detect the presence of free oxygen, a chemical so reactive that it is very implausible that a non-living world would have a lot of it. No oxygen doesn't prove no life, but lots of oxygen means life is pretty likely.

fodvor 17 Jahren

The chlorophyll in green vegetation reflects shit loads of near infra-red radiation but hardly any red so surfaces with a high infra-red to red reflectance ratio are likely to contain green vegetation. its called NDVI (http://en.wikipedia.org/wiki/Normalized_Difference_Vegetatio...) and its a very common way of detecting vegetation on earth from space. Don't know how well it'd work when you're just looking at a tiny planet billions of miles away tho...

_piusvor 17 Jahren

I believe terrestrial albedo is used to do vegetation detection on earth.

http://en.wikipedia.org/wiki/Albedo