Famous Physicist Thinks We'll Make Alien Contact Within Years, but No Saying If They'll Be Kind

Aliens may stop by for a visit sooner than later, a physicist thinks. Ye Aung Thu/AFP/Getty Images

Humans will meet alien life forms within the next century, Michio Kaku, a theoretical physicist and futurist, predicted during a Reddit AMA last week. However, he isn't quite sure whether this first encounter will be friendly.

After being asked Thursday if he thought we would make contact with alien civilizations, Kaku, a professor of theoretical physics at the City University of New York, said that while he was sticking his neck out, he believed we would make contact within this century.

According to Kaku, radio technology may soon allow us to listen in on alien conversations. Just because we can hear them and know they are there, though, doesn't mean we will understand what they are saying, he said.

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"Talking to them will be difficult, since they could be tens of light years away," explained Kaku. "So, in the meantime, we must decipher their language to understand their level of technology."

If aliens stop by Earth for an in person (or in-creature) meeting, Kaku explained that the scenario could unfold in one of two ways: Either they are expansive and aggressive, similar to to the aliens in War of the Worlds, or they are peaceful and simply want to announce that they exist.

He said he thinks the latter "is unlikely, since we would be like forest animals to them, i.e., not worth communicating with."

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Of course, there's always the possibility that aliens have already made contact with us and we just don't know about it. One popular idea about alien contact, the "Zoo Theory," suggests that aliens know we exist and observe us without making contact, just like zookeepers. The reason they do so is to allow us to evolve on our own, without outside interference.

Of course, like at a zoo, it's difficult for the aliens to keep their presence completely secret. This may explain why there are so many reports of close encounters every year.