SpaceX Does the Impossible. Again.

SpaceX's Falcon 9 rocket... on a boat... in the middle of the ocean. But it's how it got there that's the real story. Image source: SpaceX.

SpaceX did the hard work, but I'm going to claim the credit. Two months ago, in a column discussing the ongoing tit-for-space-tat feud between SpaceX and Blue Origin, I made the prediction: Sometime this year, SpaceX would succeed in landing one of its Falcon 9 first-stage rockets on a drone ship at sea.

Last Friday, they did just that.

The newsOn Friday, April 8, 2016, at 4:43 p.m. EDT, SpaceX launched a Falcon 9 rocket from Cape Canaveral, sending a Dragon cargo capsule to the International Space Station. That was the main mission -- but nine minutes after dispatching its cargo to ISS, SpaceX attempted the secondary task of relanding the core stage of its rocket vertically, on a wave-tossed boat at sea.

SpaceX had already attempted this feat four times, but each attempt had ended in failure and a fiery explosion. Last Friday, everything worked out just right, and Falcon 9 floated like a feather to land on its mothership, christened the Of Course I Still Love You. Four days later, the rocket returned to Cape Canaveral aboard its boat.

Why the news mattersWhy is this important? After all, SpaceX rival Blue Origin has been launching and successfully relanding rockets (actually, the same rocket -- the New Shepard) for months. SpaceX, too, successfully brought a Falcon 9 rocket back to Earth for a dry-land landing on Dec. 21.

That's not the point.

The point, as Discovery News recently explained, is economics. You see, when SpaceX launches a rocket from Florida, the rocket first goes up, then goes out -- east-- adding its own speed to the speed of the Earth's rotation, and accelerating the rocket's payload horizontally so that it can achieve Earth orbit. Flying east, however, means that for the rocket to return to land on its launch pad, it must fly back west, burning fuel in the process. And because a rocket can only carry so much fuel (and must carry even more fuel up to pay for the fuel it will later use to bring it back down), it's more cost-effective to bring the rocket straight back down at sea, off the East Coast.

Figuring out how to land rocketships on drone barges at sea, therefore, is an integral part of SpaceX's plan to cut the cost of space launches by 75% -- or more.

SpaceX foresees a day when the International Station will be practically covered in cheaply launched Dragon capsules. Image source: SpaceX.

What comes next?But mind you -- only a part. One successful landing does not mean that SpaceX has definitively figured out how to land rockets on barges reliably, time after time after time. SpaceX CEO Elon Musk thinks "it will still take us a few years to make that smooth and make it efficient."

To that end, Musk says "the next two or three flights are going to be drone ship landings" as well, giving SpaceX additional practice with its "drone ship landing capabilities" and showing its customers that it can reliably do this "over and over again."

But here's the really big revelation: SpaceX's next attempt at a drone ship landing will involve the same rocket it brought down last Friday, definitively proving that it can reuse its rockets for successive launch missions. Musk is taking a big PR gamble on his only successful Falcon, given the mere 1-and-4 record of successful landings at sea, to date. But he seems prepared to roll the dice nonetheless.

According to SpaceX, the now-retrieved rocket will first be subjected to a battery of tests, and test firings, to ensure it's still in working order. Then, as early as May or June of this year, SpaceX will attempt to repeat its feat by using the same rocket to launch a new payload into space.

No customer has signed up for such a mission yet, but SpaceX COO Gwynne Shotwell says the company should be able to offer as much as a 30% discount to anyone willing to place a payload aboard a used Falcon 9. Subtracted from list price, that comes to about $40 million -- a $20 million savings. Add in the positive PR from becoming the first company to send a payload into space aboard a used rocket, and I suspect customers will be lining up for the honor.

And what comes after next?After that is when things get really interesting for SpaceX, and really dicey for rivals such as Boeing , Lockheed Martin , and Arianespace.

The $60 million price tag on a SpaceX rocket launch already underprices the cost of similar launches by Boeing and Lockheed Martin (via their United Launch Alliance venture) by at least 50%. Ultimately, SpaceX's goal is to get landings at sea so certain, so routine, that the cost of launching satellites into space drops from $60 million and starts to approach the "$200,000 to $300,000" it takes to pay for just the fuel needed for a launch. Musk even goes so far as to say he's targeting "a hundred-fold cost reduction in marginal costs."

Suffice it to say that if he's anywhere close to right on the math, then it's hard to see how Boeing and Lockheed Martin will be able to compete with their U.S. rival much longer. For a more in-depth discussion of the economics of Elon Musk's reusable rocket fleet... tune back in to Fool.com tomorrow.

Boeing- and Lockheed Martin-launched Atlas V rockets are big and powerful -- but are they too pricey to compete with SpaceX? Image source: Ken Thornsley for NASA.

The article SpaceX Does the Impossible. Again. originally appeared on Fool.com.

Rich Smithdoes not own shares of, nor is he short, any company named above. You can find him onMotley Fool CAPS, publicly pontificating under the handleTMFDitty, where he's currently ranked No. 283 out of more than 75,000 rated members.The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.

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