Elon Musk says crewed flights to Mars will start in 2028 and 'city' will be built in 20 years

Elon Musk is setting his sights on the red planet, laying out a bold timeline for human settlement on Mars in a flurry of tweets.

Replying to investor Bill Ackman, who was advocating for a health-conscious ad campaign, following a peculiar piece of advice Musk gave to Brazilians about handling national economics, Ackman pointed out: "Without our health and that of our children, we have nothing. And for those who care about our economy, national debt, and deficits, there is no more important initiative,".

Musk seized the moment to elaborate on his grand plan for Mars:. "The first Starships to Mars will launch in 2 years when the next Earth-Mars transfer window opens."

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"These will be uncrewed to test the reliability of landing intact on Mars.", reports the Express US .

Musk went on: "If those landings go well, then the first crewed flights to Mars will be in 4 years."

He speculated on rapid growth in extraterrestrial expansion: "Flight rate will grow exponentially from there, with the goal of building a self-sustaining city in about 20 years."

Adding another layer to his vision, Musk commented: "Being multiplanetary will vastly increase the probable lifespan of consciousness, as we will no longer have all our eggs, literally and metabolically, on one planet."

SpaceX's digital home touts the Starship as the ultimate space ferry: "a fully reusable transportation system designed to carry both crew and cargo to Earth orbit, the Moon, Mars and beyond."

The company's website touches on some fascinating details about Mars, saying, "It is a little cold, but we can warm it up. Its atmosphere is primarily CO2 with some nitrogen and argon and a few other trace elements, which means that we can grow plants on Mars just by compressing the atmosphere."

"Gravity on Mars is about 38% of that of Earth, so you would be able to lift heavy things and bound around. Furthermore, the day is remarkably close to that of Earth."