Alternative life forms
The universe is probably teeming with life but in forms that we do not recognize or understand or are capable of understanding from a chemical/physical point of view.
I know that I am a pressimist and as much as I can understand the desire to search elsewhere I always feel that there is far more need to take care and improve whats already here..
If we were to discover an alternative lifeform I am sure that they would be disgusted at what we are doing with the planet that we already have..
Before venturing elsewhere we need to take care of GAIA before se decide to take care of us... Then we should begin our ventures elsewhere.