interesting spectral analysis of the sun

[river]

http://www.ted.com/talks/lang/en/gar...de_a_star.html

in the first 3 , 3 and a half minutes is basic stuff but from there to about 1:30 minutes he says that 15% of the spectral lines of the sun has yet to be indentified

why ?

the rest of the talk is still very interesting

he talks of using spectral lines to discover life on other planets

[rossjoseph]

That was really very interesting. I have always been interested in knowing unique analysis of the sun.

[Aqueous Id]

15% of the spectral lines of the sun has yet to be indentified why ?

Each element has its own spectrum. They are all superimposed, so we detect them added together into a composite. He is saying that after finding the proper mix of chemicals that comes closest to the spectrogram and then subtracting it out, 15% of the original spectral lines remain, but they don't fit the signature of any known chemicals. It means this is a puzzle that remains unsolved, in spite of the long history of studying the sun.