A panel at the Museum of the Future addressed the way ahead for the space industry.
Space agencies such as Nasa have plans to send astronauts to Mars, while the UAE set a goal of building a settlement there by 2117.
But a panellist at the event predicted that the kind of investment that is needed to colonise Mars would only come when humans on Earth face an existential crisis.
Mark Beer, of Asgardia, an international project that is trying to set up a space nation, said environmental and health crises could drive that transition.
“Elon Musk thinks it's going to be a billion people living on Mars by the end of the century but what will be the accelerator? What will drive this transition to be living on Mars?” he said.
“Unfortunately, I predict it to be an existential event. It will not happen organically.
“It will be war, disease, climate or famine. These existential threats are what I think would force us to look at living on another planet.”
Astrophysicists have often criticised Mr Musk’s plans for Mars, saying that the planet has a hostile environment.
Terraforming — a process that changes a planet's conditions so it becomes habitable — has been suggested as a solution to making the Red Planet suitable for humans, but that could take millions of years.
There have also been calls for billionaires to invest in healing Earth from climate change instead of spending billions on trying to colonise other planets.
“What we're hearing is the challenge of cost — the cost of moving organic matter into another planet or transporting the infrastructure that we can build on another planet,” Mr Beer said.
“If we look back in history, at the point of which the maximum investment has been made financially in changing the world, it tends to come out of existential threats.
“The Second World War gave us the first electric computer … it gave us a 125,000-person nuclear programme to create an atom bomb,” he said.
“And that's why I think for space, it will not come out of that organic discussion, but the need.”
However, there are still many challenges that need to be addressed before humans can colonise Mars, including deadly radiation, cold and an unbreathable atmosphere.
Diego Urbina, team lead of future projects and exploration at a company called Space Application Services, said “we’re on the right track” for achieving those goals.
“I believe we’re taking the right steps — we’re lowering the cost of access to space with reusable rockets, which is quite important,” he said.
“And we're also creating this space economy that will make it more feasible to have these future space settlements. So I think we're on the right track, but it’ll take few decades to be able to get there.”
He said a lot more investment is needed to further accelerate the process.
The Dubai Future Forum concludes on Wednesday.