He has consistently stated that this is the ultimate goal of SpaceX, as he believes it is fundamentally necessary to ensure humanity’s long-term survival as a species.
The timeline for achieving this has been pushed back several times, though the earliest inter-planet Starship cargo missions could take place in 2024 or 2026 when the orbits of Earth and Mars line up. It is hoped that a completely self-sufficient Mars colony could be set up by around 2050, though Musk is yet to speak publicly about what comes after.
In response to a question from one of his Twitter followers about the Great Filter – a philosophical concept relating to the probability of a species reaching an advanced-enough stage of development to explore outer space before going extinct – Musk explained what his hopes were for humanity once Mars has been colonised.
“If we are able to make life self-sustaining on Mars, we will have passed one of the greatest filters. That then sets us up to become interstellar,” he replied. “Earth is ~4.5B years old, but life is still not multiplanetary and it is extremely uncertain how much time is left to become so.”
SpaceX is currently preparing for the first orbital launch of its Starship rocket, which will see it lift off from Texas and land off the coast of Hawaii early next year.
There have already been several high-altitude flight tests of the next-generation rocket, with all but one ending in a fiery explosion.
Once complete, the Starship craft and its accompanying booster rocket will be the most powerful rocket ever built, capable of producing more than twice the thrust of Nasa’s Saturn V rocket used during the Apollo missions.
SpaceX is also building them to be rapidly reusable, which would transform space travel and allow fleets of them to shuttle between planets.
“In order for life to become multi-planetary, we’ll need maybe 1,000 ships, or something like that,” Musk said earlier this month during an event with the US National Academy of Sciences.
“Long term, it’s essential for preserving the light of consciousness. Eventually something will happen to Earth, hopefully not soon, either natural or man-made that would cause the end of civilisation. The probable lifespan of civilisation is much greater if we’re a multi-planet species.”
The exact launch date for the next major Starship test is yet to be set, though Musk said he thought it was unlikely to be a complete success, adding, “but I think we’ll make a lot of progress.”