When Elon Musk founded SpaceX in 2002, the ultimate goal was to reach Mars. Almost two decades later, the company has gone through steady developments and became the first private company to send astronauts to the International Space Station with 48 missions scheduled for 2021.

However, behind the scenes, Musk's team is busy in fulfilling the ultimate goal, sending astronauts to Mars. With its Starship rocket undergoing testing, Musk says in the next four years, the company will be able to launch its first Mars mission, albeit unmanned. That's an ambitious target for a private company like SpaceX. Although the Starship launch vehicle has had four successful tests, it is still some time away from completion.

But the SpaceX CEO believes it will be ready for even a Moon mission by 2022 and a Mars mission by 2024. "I think we have a fighting chance of making that second Mars transfer window," he said during a discussion with Robert Zubrin at the 2020 Mars Society Virtual Convention.

Starship rocket
Artist's impression of SpaceX Starship rocket that will one day carry humans to Mars Wikimedia Commons

Narrow Window

To cover a 40.38-million-mile distance from Earth to Mars, a rocket will need to carry an enormous amount of fuel. But during Mars opposition, the distance reduces to 34.65 million miles and that's the optimal window to launch a rocket to the Red Planet. Mars opposition is the time when Sun and Mars are on directly opposite sides of Earth. This opposition occurs every 26 months from mid-July to Mid-August.

That's a narrow window that space agencies have been targeting for launch. The next optimal launch window will be in 2022 followed by 2024 and that's the target for Musk. He believes it will give the company enough time to be mission-ready. So far, Starship launch tests have been successful four times. But it hasn't been tested to reach the Earth orbit yet. Musk's target is to successfully send a Starship rocket to orbit by next year

"We're obviously venturing into unknown territory so it's not as though I have all these secret dates and I'm just keeping them from people. But these are just guesses. I am about 80 to 90 percent confident that we will reach orbit with Starship next year," Musk said.

Mars opposition
Launch windows to Mars comes only once in 26 months and Elon Musk is aiming for 2024 window NASA

Starship Rocket

The other problem with a rocket that could transport heavy payload — scientific equipment and instruments — to Mars is that it will need to carry a lot of fuel. Thus, it needs to be bigger, better and efficient. At present, all the expandable rockets do not meet the criteria. Even if it does, it would not be cost-efficient either. Thus, SpaceX's Big Fat Rocket will be combined with a Falcon Heavy to create Starship with the capability to carry crew and heavy payload.

Musk estimates that such a rocket must carry at least five million tons of payload to the orbit so that it can transport a million tons to Mars. Currently, the final piece of a rocket that is capable of achieving such a feat doesn't exist and SpaceX is trying to accomplish that in an overly ambitious timeframe.

Musk said the Starship will be able to complete high volume flights in 2022. "I'm trying to make sure that our rate of innovations increases, and that it doesn't decrease," he added.

Mars Colonization

For some time now, various scientists have suggested that leaving Earth would be the only option for humankind to survive as the planet would become inhabitable in the future. It could be due to a meteor or nuclear Armageddon. Late scientist Stephen Hawking and Musk are two of them. Mars, for now, is the only planet in the solar system with the potential to sustain life and colonizing it has been one of the most told stories in the science-fiction genre.

But Musk has no interest in colonizing Mars. He only wants to enable transportation to Mars so that others can colonize the Red Planet if an apocalyptic situation arises. And reusable rockets are the only option according to him.

"To build a self-sustaining city on Mars, we have to achieve full and rapid usability. It is only relevant when it is rapid and complete. In the absence of radical innovation, there is no chance of meeting the goal. If we have to make humans multi-planetary species before it's too late, we have to be competitive," Musk said.