The great scientist Stephen Hawking has warned other scientists against beaming or giving any messages or signals into the universe and showing our presence as it could turn out to be catastrophic. According to him "If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans." The idea that we might not be alone in this vast universe has made Scientist's cautiousness to explore and different ways to communicate with the aliens and sending them signals from Earth. But Stephen Hawking again warned them against it as one has no idea of how they would react. The search of the aliens are on from the very beginning, in fact scientists have found out proof, which shows that they once visited on our Earth. The team would be using powerful radio telescopes which will send the data to nearby stars and planets. However, US scientist and NASA consultant David Brin has warned that any contact with aliens would "transform human destiny, and that it should only be conducted if the entire world is onboard.