Alien invasion: Scientists weigh in on Hawking's warning about aliens - latimes.com

Famed physicist Stephen Hawking set off chatter in the scientific community in late April when he posited the existence of intelligent aliens on his new TV series, "Into the Universe with Stephen Hawking" —adding that it would be best for human beings to avoid contact with them.

Hawking speculated that such aliens would likely be nomads, living in ships after sucking their own planet dry of resources, and hopping from one interstellar refueling station to the next. Earth, he said, shouldn't do anything to encourage their visit.

"If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn't turn out very well for the Native Americans," he said.