DECATUR - The sky, apparently, is falling.

Its point of impact? The back yard of William and Anna Mae Beals at 6060 Thomas Road.

A slab of ice about the size of a concrete block hurtled from the heavens Wednesday morning toward their home in southeast Decatur.

Fortunately, no one was hurt.

But their neighbors were shaken when they saw the chilling visitor land.

Darlene Scribner was sipping coffee and watching birds out her backyard window with her sister and cousin when a white flash descended toward the earth.

"We were shocked," said her sister Jo Ann Wheeler.

"I've never seen anything like that before in my life," said her cousin, Joyce Wetzel.

So where'd the icy chunk come from?

"I don't have a clue," said a puzzled Anna Mae Beals.

Could it have fallen from an airplane's wing? That's unlikely, aviation experts say. Ice can cause serious problems if not removed from a plane's wings.

"We take great pains to make sure airplanes are de-iced," said Elizabeth Isham Cory, spokeswoman for the Federal Aviation Administration.

"Something that big on an aircraft doesn't sound right," said Gene Marcinkowski, Decatur Airport director.

Could the ice cube be the frozen flush of a portable toilet aboard a high-flying plane? Nope. Waste is removed when a plane touches down. Plus, the neighbors concluded, the ice cube was white and clear - not the typical colors of a potty flush.

Could it be a freak weather phenomenon? The chunk of ice initially stumped even Jim Angel, state climatologist with the Illinois State Water Survey.

"That's a real mystery," Angel said.

Angel then recalled reports of large ice chunks falling from the skies in places as far away as Spain. The cool slabs usually fall in January, February and March and can weigh as much as 30 pounds.

Experts call them megacryometeors. It's not really clear why they fall.

"One of these things is very weird," Angel said. "It's not like it hasn't happened to other people. It happens rarely, but it does happen."

Mike Frazier can be reached at mfrazier@;herald-review.com or 421-7985.