Stephen Hawking: we should not response to "extraterrestrials" (Aliens)

Stephen Hawking, the British astrophysicist scientist said if the extraterrestrials contact with humans should behave with caution in response.  According to Asr-e-Iran quoted from "Huffington Post", Hawking spoke about this opinion in his TV show with name of "Stephen Hawking's favorite places". He pointed to discover of the "Alpha Centauri" stars near the earth (40 trillion kilometers) said if the extraterrestrial contact with earth; we must be very cautious in giving their callback. He pointed to the newly discovered "extra solar planets" named "Gliese 832 C" which is only 16 light years far from Earth and its weather conditions has strong similarities with Earth, raised this issues. He said: "making contact with a most progress culture in another planet could have bad results like encountering the natives of America with "Christopher Columbus". Hawking said: if there is smart life in nearby of earth, we should know how that is. We should know them before they contact us. Maybe one day we receive a massage from this planet (Gliese 832 C). But we should consider these concerns in giving response to their massage. We should be very caution". Also he emphasized that he love to experience living on Gliese 832 C. it should say now a $ 100 million project is running with collaboration of  "Yuri Milner" Russian billionaire and CEO of Facebook Mark Zuckerberg under the Hawking's supervision which its aims is finding clues of intelligent life on other planets in the cosmos. The aim of this ambitious project is building space probes in very small size (the size of a postage stamp) that just has a few grams and can travel to distant star systems and transmit information to the earth. The small probes of this project are multi-gram chips that are equipped with cameras, communication devices and navigation and propulsion photons. The construction time of first explorers of this project is estimated 20 years (2035) and then the first explorers of project will go to the space and if this project be successful, the first transmitted information by these probes will arrived to the Earth 4 years after launch.