Dick Uliano, wtop.com

WASHINGTON – Discovery, bound for the Air and Space Museum Tuesday, was the the shining star of the space shuttle program.

Following the loss of space shuttle Columbia, it was Discovery NASA turned to get back into orbit.

It played a similar role for the Challenger 17 years later.

“Discovery was an amazing machine. It always, on all of its flights, worked flawlessly,” says former astronaut Pinky Nelson who flew on Columbia and Challenger, and was aboard Discovery’s 1988 return flight.

“It was the real work horse of the fleet.”

Discovery flew 39 space flights and 149 million miles around Earth. It also deployed the Hubble Space Telescope which redefined the world’s understanding of space.

Nelson believes Discovery was NASA’s best.

“Columbia and Challenger rank up there too, But Discovery, probably, is the one vehicle the program is most proud of,” says Nelson.

Nelson says it showed that the world could gain regular access to space — and that isn’t as easy as people thought.

Watch the video below for highlights of the Hubble Space Telescope being launched into orbit.

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