There and Back Again — A Rocket’s Tale

On Monday history was made. Returning to flight after six months on the ground in the wake of the failure of the CRS-7 mission, Elon Musk and SpaceX accomplished something most people in the industry thought was impossible. For the first time ever a rocket stage that delivered a payload to orbit turned around and returned, landing safely on its tail.

To get into orbit your rocket must overcome both gravity and drag. To do that it’s important to understand how the design of a rocket affects its flight, and why landing it again is so hard.

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"A Dragon by the Tail"

They promised us flying cars

We may be living in the future, but it hasn’t entirely worked out how we were promised. I remember the predictions clearly: the 21st century was supposed to be full of self-driving cars, personal communicators, replicators and private space ships.

Except, of course, all that has come true. Google just got the first license to drive their cars entirely autonomously on public highways. Apple came along with the iPhone and changed everything. Three-dimensional printers have come out of the laboratories and into the home. And in a few short years, and from a standing start, Elon Musk and SpaceX has achieved what might otherwise have been thought impossible: late last year, SpaceX launched a spacecraft and returned it to Earth safely. Then they launched another, successfully docked it with the International Space Station, and then again returned it to Earth.

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