Are humans doomed? Stephen Hawking, the renowned physicist, thinks so. Hawking said that humanity will only have 1,000 years left, with an impending asteroid collision possibly wiping out humans by 3016.

During a speech at the Oxford University Union, Hawking noted that climate change, nuclear weapons and genetically engineered viruses could pose a threat to human existence. He added that the longer humans stay on Earth, the higher the risk of Earth's demise. As a solution, Hawking said that humankind must explore outer space in order to survive.

“We must ... continue to go into space for the future of humanity. I don’t think we will survive another 1,000 years without escaping beyond our fragile planet," Hawking said.

“Although the chance of a disaster to planet Earth in a given year may be quite low, it adds up over time, and becomes a near certainty in the next thousand or ten thousand years. By that time we should have spread out into space, and to other stars, so a disaster on Earth would not mean the end of the human race," he added.

However, humans are not the only threat to Earth. In a video, Hawking also said that asteroids could hit Earth in the future, Inquistr reports.

“One of the major threats to intelligent life in our universe is the high probability of an asteroid colliding with inhabited planets," Hawking said.

Despite NASA and other space agencies tracking near-earth asteroids, these space agencies could only trace thousands of them in space -- a small percentage of the estimated 600,000 known asteroids in the solar system.

“We only know about 15 or 20 percent of the objects which are larger than a few hundred meters in size. If these bodies impact Earth, they can cause regional damage across a whole country or even a continent," said astronomer Patrick Michel.