Perception...

There's a question I want to propose to NASA but I'm not sure how to spend my time finding the right person to address the question to. Scientists have found ingenious ways to determine all kinds of information on stars, planets, galaxies etc. out in the universe. Whether we use the Hubble Telescope or even the newer Cassini-Huygens mission, it seems that there are conclusions made about deep space objects that doesn't sit quite well with me. I'm not questioning the validity of the data or inaccurate research but can we really say there is or isn't intelligent life elsewhere?

I saw a pretty next picture a few months back that the Cassini spacecraft took of earth as viewed from a Saturn-ish distance. It was Saturn right? Regardless, all earth looked like was as a typical star would look like to us as we stand on earth.

So without any bias from obvious knowledge, can the Cassini spacecraft detect and accurately 'discover' life on our very own planet?