plainly see the squiggly lines that this is the planet that has a definite clear oxygen line, and there's definitely carbon dioxide and methane. those signals were all tangled up together in the colors of the earth. and that was what we called the spectrum of a habitable planet. when i first heard of the search for extraterrestrial intelligence, i thought that this was by far the most interesting thing to study in all of astronomy. finding out that there are other civilzations and the observable universe would be pretty much right there at the top of things you could find out. >> you're working with jill tarter in the steady institute. >> absolutely. jill was the study pioneer. the search for extraterrestrial intelligence. i met her shortly after the