Elon Musk has long made it known that his eventual goal is to make it to Mars, and according to new statements made by the billionaire, it looks like that time may be approaching even faster than we thought.

On Friday, the billionaire Tweeted that Mars was a “fixer upper of a planet” but noted that it had “great potential.”

One of Musk’s 100 million followers then asked him what the estimated time frame would be for “creating a self-sustaining civilization” on the red planet and clarified that by self-sustaining he meant not needing or relying on materials or supplies from Earth.

Musk’s answer?

“20 to 30 years from first human landing if launch rate growth is exponential,” the billionaire penned in response. “Assumes transferring ~100k each rendezvous and ~1M total people needed.”

The Tesla CEO’s commentary brought in mixed responses, with many shaming the billionaire for wanting to start anew elsewhere without first fixing the problems on Earth.

“If we can’t get it right here with the perfect environment & resources, how are we going to make it work there,” one user pointed out in response.

“Please. Please focus on fixing the MANY problems we have on this planet first,” said another. “With your resources you truly could.”

Though it’s unclear exactly when that initial landing could and would take place, Musk has previously hinted that it could be as soon as 2029, according to a Tweet he responded to back in March that asked him to predict when humans would make their first landing on Mars.

On the Full Send podcast, fellow billionaire Mark Cuban talked about how he congratulated Musk on the recent birth of one of his children, though he didn’t specify which one.

“I’m like, ‘Dude, congratulations, how many you going to have,'” Cuban said, referring to Musk’s children. “He sends me a text back, ‘Mars needs people.'”

As of Monday afternoon, Musk’s net worth was an estimated $232.2 billion.