| [I'm not an expert is spectroscopy, but let me guess.] The bump at 4.3um looks real, and it seams to be an standard absorción of CO2. https://www.quora.com/Does-CO2-absorb-all-infrared-frequenci... The bump at 1.2, 1.4 and 2.4um looks real. I found this showing a peak for CH4 at 2.325um. http://www.astrochem.org/data/CH4H2O.php [Sorry for the sources, but I'm not an expert is spectroscopy.] My guess is that they assumed something like a% * CH4 + b% * CO2 + c% * H2O + others and get the best fit for a%, b%, c%, ... using the white points. Later, using these numbers they draw the blue line. The peak for DMS is not clear for my untrained eye, so I can't guess what they did there. (Perhaps it's just the best fit.) It would be nice to see the a graph of the blue line they guessed with DMS and a superimposed red line with and atmosphere with an alternative atmosphere where the DMS is replaced with something uninteresting (N2? H2O? More CH4? I have no idea what is uninteresting here.) |