UPDATED 07/08/11 10:29 a.m.

CHICAGO (CBS) — The president of the Adler Planetarium says he feels a sense of sadness that there will no longer be shuttles flying from earth to the International Space Station.

But Paul Knappenberger, an astronomer, also says it’s time to move on from the program.

LISTEN: Newsradio 780’s John Cody reports

As WBBM Newsradio 780’s John Cody reports, Shuttle Flight No. 135 commenced Friday. It was the final blast-off for the Space Shuttle program, which will conclude permanently when the shuttle returns.

It was also the 33rd launch for Space Shuttle Atlantis, which is scheduled for a 12 day resupply mission to the International Space Station.

Knappenberger said the shuttle program allowed the construction of the Space Station, and repairs to the Hubble deep space telescope.

“I feel a sadness that we’ll no longer have the shuttles. They were remarkable vehicles. They were developed in the late ’70s, so that’s the technology that went into them,” Knappenberger said. “But they were truly remarkable vehicles that allowed us to travel from the surface of the earth up into low-earth orbit, and come back and land like an airplane, and go back up there again.”

Knappenberger says the old shuttle just became too costly to continue, with the money better spent supporting the next step – exploration of the asteroids and Mars.

“They probably still had several years of service left in them. They were designed that way,” he said. “But on the other hand, if you have a limited amount of money to spend on space exploration, at some point, you just have to say, we have to stop spending money on 1970s vehicles, and build a new one.”

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