US firm SpaceX aims for its next big launch into orbit Sunday — the first of 12 flights in its $1.6 billion contract with NASA to bring supplies to and from the international space station.

The launch is the next step in American efforts to commercialize the space industry, in the hope of keeping down costs and spreading them among a wider group than governments alone.

SpaceX, owned by billionaire Paypal co-founder Elon Musk, is one of several private companies working with the US space agency to send flights to and from the space station. NASA has been relying on Russian spacecraft for the last year, after retiring its fleet of shuttles.

On Sunday, SpaceX’s Falcon 9 rocket is scheduled to fire at 8:35 pm (0035 GMT) to launch the company’s Dragon capsule from Florida’s Cape Canaveral into orbit, loaded with around 1,000 pounds (455 kilograms) of supplies.

However, the latest reports indicate that a 40 percent chance of unfavorable weather could push the launch back one or two days.

This is to be SpaceX’s second flight this year: in May, the company proved its mettle with a test flight to the ISS, conducting a near flawless nine-day trip to deliver cargo to the $100 billion orbiting outpost — the first time a commercial outfit had sent its own capsule there and back.

Musk said he aims to massively expand the program.

‘Next year, we’re aiming to do probably four to six launches and then double it again the year after,’ he said during an online ‘hangout’ on Google+.

‘The ultimate thing is to try to get spaceflight as routine as air flight. I don’t think it can quite get there but it can get closer than it has been in the past,’ he said.

Like traveling by airplane, Musk said he hopes one of the payoffs will be that everyday people, not just the rich, can one day afford a seat.

‘Right now there are a lot of people that buy seats on the Russian Soyuz,’ he said. ‘If we could offer them at a lower cost, we could expand the market.’ ‘Perhaps it can be brought down to being only 10 times more expensive’ than a seat on an airplane, he said. ‘It can happen. If we can make rapidly and fully reusable spacecraft.’

NASA administrator Charles Bolden added that part of commercializing the space industry will mean the private sector building new low-orbit destinations where companies can use the zero gravity environment for things like materials processing and pharmaceuticals research.

‘That’s what we’re trying to do, is facilitate the true development of a real commercial industry where the government is an anchor tenant but not the primary source of income,’ Bolden noted, during the Google+ chat.

SpaceX says it has 50 launches planned — both NASA missions and commercial flights — representing about $4 billion in contracts.

But the cargo on Sunday’s launch is all government: the manifest lists supplies from the Japanese and European space agencies, in addition to ones from NASA.

Jeff Foust, an aerospace consultant and the editor of TheSpaceReview.com said the industry is at the start of ‘a very slow transition’ from something that is all government to something involving the private sector.

‘NASA can’t keep doing everything. At some point it has to start turning over the things that are more routine,’ like ferrying supplies to the space station.

If Sunday’s launch goes as planned, the Dragon capsule should reach the space station by Wednesday, where it should stay for two weeks. It is scheduled to return to Earth — splashing down off the coast of southern California — on October 28, carrying about 734 pounds (333 kilograms) of scientific materials.

So far, SpaceX has only sent unmanned flights into orbit, but the company aims to send a manned flight within the next three or four years. It is under a separate contract with NASA to refine the capsule to make it crew-capable.