SAN FRANCISCO (MarketWatch) — SpaceX will attempt to land a booster rocket on a drone ship on Saturday, a first step toward saving money — and making history — by deploying fully reusable rockets to propel cargo ships bound for the International Space Station.

The privately held space company called off the mission, its fifth, earlier this week due to a technical problem. The nail-biting moment is now slated for 4:47 a.m. Eastern from Cape Canaveral Air Force Station in Florida.

The flight’s goal is to launch SpaceX’s Dragon cargo ship to the ISS to deliver supplies. NASA said the Dragon will arrive at the space station on Monday, carrying more than 5,000 pounds of supplies, from food to scientific materials. NASA will televise the launch starting at 3:30 a.m. Eastern on Saturday.

SpaceX plans to land the booster rocket, called Falcon 9 first stage, on a custom-built ocean platform it has called the autonomous spaceport drone ship. The drone is 300 feet by 100 feet, with wings that extend its width to 170 feet.

That may sound huge, but not for the booster rocket, which is about 14 stories tall. And the drone ship will not be anchored, although it has engines to help it stay in place.

Elon Musk, the chief executive of electric-car maker Tesla Motors Inc. TSLA, +4.42% , is the CEO of SpaceX as well and has previously tweeted details of the upcoming attempt.

SpaceX has said its chance of success are “not great” — 50% at best, according to the company’s website. It has been successful with soft landings, but a precision landing on the drone spaceport is “significantly more challenging,” it said. SpaceX was founded in 2002 with the “ultimate goal” of enabling humans to live on other planets, according to the website.

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