Professor Stephen Hawking says he is not alone in believing humans need to find a new planet to live on within 100 years if it is to survive.
As part of the BBC's new science series Tomorrow's World, Professor Hawking said he thinks due to climate change, overdue asteroid strikes, epidemics and population growth, humans will need to find a new planet to populate within a single lifetime - revised from the 1,000 year time limit he gave last November.
Speaking at The Royal Society in London ahead of the Starmus IV festival, Professor Hawking said he and others will elaborate on this view at the science and music festival held in Trondheim, Norway.
"I strongly believe we should start seeking alternative planets for possible habitation," he said. "We are running out of space on earth and we need to break through technological limitations preventing us living elsewhere in the universe."
"I am not alone in this view and many of my colleagues will make further comments at the Starmus next month."
Hawking isn't the only one who has advocated for a multi-planet species. SpaceX boss Elon Musk has grand plans to launch space colonies in the next 100-years and Nasa has said its Mars missions could help to put humans permanently on other planets.
Neuroscientist and Nobel Laureate Edvard Moser, who will also be at the Starmus event, said Professor Hawking has emphasised the need for science in society, at a time when communicating science is more important than ever.
"I think what it comes down to is explaining how the data of climate change has been collected and how the scientific process works and how data is tested over and over again and I think it's an educational job.
"I don't think there's a single sentence I could say that would change anyone's mind overnight but I think it's a long term thing, Moser said. "There are many people who don't take advice from science for granted anymore, however I want to say this is not just an issue about the current president of the United States it's actually a concern in all countries". Since Trump took office in January, his administration has removed climate change policies and references from the Whitehouse website. Thousands of scientists also marched in protest at his policies.
"One example is climate change which is something that scientists have to fight against other types of evidence for a long time so I think you shouldn't take for granted that science is perceived as the source of the right answer. You have to explain to the public how science works," he said.
"Science should not be an elitist activity, it is something that should be driven by society for the benefit of society and we should aim for having everyone agree with that."