CHICAGO (WBBM) — The famous moon rock displayed along Michigan Avenue has been removed, but it’s only temporary.

The moon rock sat for years, on loan from NASA, in a display case in front of Tribune Tower. Alongside it were a poster of the Tribune’s front page depicting Neil Armstrong’s historic walk and a video screen that has been blank for some time.

Tribune Vice President Gary Weitman said the newspaper returned the rock to NASA several week ago. But he said that NASA has agreed to send another moon rock suitable to be embedded in the walls of Tribune Tower, next to chunks of the Taj Mahal, White House, Lincoln’s Tomb, the Roman Colosseum and nearly 150 other places of note.

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The collection of rocks and stones from famous sites across the earth was begun when the late Col. Robert R. McCormick ruled Tribune Tower as publisher.

“Chicago Tribune correspondents supplemented the collection with pieces obtained while on overseas assignments,” Weitman said.

Although additions have been less frequent in recent years, Weitman said a piece of twisted metal from the ruins of the World Trade Center was most recently incorporated into Tribune Tower’s walls.

Weitman said in most cases, the stones must be authenticated and may remain in storage for 10 years or more to judge whether they are still important enough to warrant inclusion.

But there’s no question about the moon rock, which will come directly from NASA, which has the world’s largest repository of moon rocks.

Weitman said the new moon rock will have special protection the other Tribune Tower rocks lack — a Lucite sheathing.

For now, visitors will have to be satisfied with the other stones, which include a piece of rock from Craters of the Moon National Monument, in Idaho.

He said the new moon rock is expected to be embedded by spring, depending on the weather and when the rock arrives.

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