Elon Musk on Wednesday revealed plans for what could become one of the largest initial public offerings in history for a space company currently losing billions of dollars a year.

Documents filed on Wednesday show Musk's SpaceX lost $2.6 billion from operations last year on $18.7 billion in revenue, and the losses kept piling up at the start of this year, too.

Still, the initial public offering is expected to rank among the largest ever, possibly surpassing the current title holder, Saudi Aramco, the oil giant that went public seven years ago.

The prospectus did not put a dollar figure on the amount Musk hopes to raise but various reports have put it at $75 billion or so. The company has said the money will help to finance projects to put men on the moon and maybe some day Mars in his quest to make making humans an intergalactic species as it faces existential threats that could wipe out civilization.

"We do not want humans to have the same fate as dinosaurs," the filing stated.