Vakoch added that due to the limited extent of current radio technology, any radio signals from alien civilizations detected by the dish would have to be strong and deliberately sent with contact in mind, rather than randomly fired out from radio or TV equivalents."We'd only be able to find the sort of signals that FAST will be looking for: narrow band signals, something that would have a lot of energy put into a carrier," he said. "An interstellar beacon saying: We are here."*It's all very well aiming a massive dish at the sky and listening, but if life indeed does exist beyond Earth, is it intelligent according to the definitions we understand? Would it have the technology to send a radio message to us? Would it event want to? And why?
So, what are the odds of these potentially super-advanced aliens making contact through FAST? Vakoch said that although it feels like a long shot, many previous astronomical discoveries also once seemed improbable.For example, after pulsars were discovered in 1967 they were nicknamed LGM (short for "little green men") because astronomers had never before observed anything not created by humans that pulsed with such regularity. The first exoplanet was discovered in 1992, and now many exoplanets that are potentially able to sustain life have been documented. FAST is almost certain to add richly to the timeline of astronomy.
"Our civilization has only been evolving for tens of thousands of years. Other civilizations could have had billions of years to evolve."