NEW YORK (AP) — Elon Musk’s space exploration company has filed preliminary paperwork to sell shares to the public, according to two sources familiar with the filing, a blockbuster offering that would likely rank as the biggest ever and could make its founder the world’s first trillionaire.

A SpaceX IPO promises to be one of the biggest Wall Street events of the year, with several investment banks lining up to help raise tens of billions to fund Musk’s ambitions to set up a base on the moon, put datacenters the size of several football fields in orbit and possibly one day send a man to Mars.

SpaceX did not respond immediately to a request for comment.

Exactly how much SpaceX plans to raise has not been disclosed but the figure is reportedly as much as $75 billion. At that level, the offering would easily eclipse the $29 billion that Saudi Aramco raised in its 2019 IPO.

The offering, coming possibly in June, could value all the shares of SpaceX at $1.5 trillion, nearly double what the company was valued in December when some minority owners sold their stakes, according to research firm Pitchbook, before an acquisition that increased its size.

Musk owns 42% of the SpaceX now, according to Pitchbook, though that figure will change with the IPO when new owners are issued shares. In any case, he is likely to pierce the trillion dollar mark because he is already close, with a net worth estimated by Forbes magazine at $823 million.

In addition to making reusable rockets to hurl astronauts and hardware into orbit, SpaceX owns Starlink, the world’s largest satellite communications company. The company also recently brought under its roof two other Musk businesses, social media platform X, formerly Twitter, and artificial intelligence business, xAI, in a controversial transaction because both the seller and the buyer were controlled by him.

SpaceX has become the biggest commercial launch company in its industry, responsible for sending payloads into orbit for customers across the globe, but has also benefited from big taxpayer spending. That has raised conflicts of interest issues given that Musk was the biggest donor to President Donald Trump’s campaign and is still a big backer.

In the past five years, SpaceX won $6 billion in contracts from NASA, the Defense Department and other U.S. government agencies, according to USAspending.gov.

Among current SpaceX owners is Donald Trump Jr, the president’s oldest son. He owns a shares through 1789 Capital. That venture capital firm made him a partner shortly after his father won the presidency for a second time and has been buying up federal contractors seeking to win taxpayer money ever since.

The White House and Trump himself have repeatedly denied there are any conflicts of interest between his role as president and his family’s businesses.