The “Money Rocket” was a rocketship built by Gyro Gearloose.
This handsome rocket-ship was built in 1960 by Gyro Gearloose as a way to kill time "while he was waiting for some water to boil", and was soon bought by Scrooge McDuck, who first used it to get to one of his money deposits before the Beagle Boys got there to rob it, and then later to move said money to an even safer destination: the Moon.
As Huey, Dewey and Louie Duck had sneaked aboard, though, Gyro's well-calibrated trajectory was thrown off and the Rocket instead careened towards Jupiter, where it crashed. What was left of the Rocket was later gobbled up by the metal-eating locals, forcing Gyro to build another, much less impressive rocket for the trip back home.
One of Gyro's first machines to do so, the Money Rocket was apparently able to travel at up to the speed of light, though a side-effect was that for the first few moments of flight internal dimensions would become distorted, making people and objects within the ship look like rubbery caricatures. The artificial gravity of the ship, however, could counteract this.
Behind the scenes
The Money Rocket appears in the 1960 story Uncle Scrooge's Money Rocket and its novelizations.