A space-age version of the rusty springs under old pickup trucks will help NASA fix the most pressing technical problem with its high-tech new rocket to send astronauts back to the moon.

NASA is going to use 17 super-sized shock absorbers in its not-yet-built rocket to keep the top from shaking too much for astronauts, agency officials said in a Tuesday press conference.

For close to a year, NASA engineers working on the new Ares 1 rocket and Orion crew capsule have been wrestling with the problem of heavy vibrations from the massive rocket engines about two minutes after launch. If the vibrations are not dampened, it could potentially harm the crew or make it too difficult for them to operate for a few seconds.

Officials on Tuesday said they have settled on a solution that is similar to what smooths the rides of pickup trucks: shock absorbers. But NASA's shock absorbers will be big and mostly remote-controlled.

The plan is to install 16 canisters in the bottom of the rocket with 100-pound weights attached to springs. Battery-powered motors will move the weights up and down to stop vibrations. Those are essentially remote-controlled shock absorbers, said Garry Lyles, who headed the team of NASA engineers tackling the shaking problem.

A 17th shock absorber will be a ring of weights and springs near the middle of the rocket.

The fix will add weight, but the rocket can handle it, said Ares projects manager Steve Cook. There are still other daunting technical problems facing the moon program, but Cook said: "There's nothing on our risk list that I would term a showstopper or major issue that we can't deal with."

In the last few weeks, the moon program has had to push back key launch dates, suffered a key contracting setback, and got chided by a NASA safety panel.

The agency hopes to launch the first Ares 1 rocket with a crew by early 2015 and send astronauts back to the moon by 2020.

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On the Net:

NASA's return to the moon program: http://www.nasa.gov/mission_pages/constellation/main/index.html