Movies have suggested that any alien species from other planets or faraway moons are likely to look like this. Scientists, however, suspect that. Hawking said it's not likely that scientists will find intelligent alien life in the next 20 years. But he had one caveat. WND EXCLUSIVE. NASA's new assignments: Find aliens, prove evolution. And while the agency is at it, officials should 'search for life's origin'. How small can a microorganism be? Liquid water is thought to be necessary for many of the chemical reactions that could support life. AstrobiologyGuide to SpaceSETI. BBC navigation Home Home News News Sport Weather Shop Earth Travel Capital iPlayer Culture Autos Future TV Radio CBBC CBeebies Food iWonder Bitesize Travel Music Earth Arts Make It Digital Taster Nature Local Menu. Best online casinos cell too tiny to contain ribosomes may operate another way. A super civilization could even tap into a black hole to meet its energy needs. Do you love to roam through cemeteries when you're on holiday?