Amateur investigator John Lutz is convinced that a basketball-size chunk of mysterious green ice that fell out of the sky and into an Eastern Shore trailer park was an ice meteor.

Fred Farrar of the Federal Aviation Administration says it was probably frozen refuse from a leaky airplane toilet -- a rare but not unknown hazard of modern aviation.

The "Chicken Little" saga started about 3 p.m. Saturday, according to Thomas I. Andrews, a retired poultry company manager who lives in the Swann Haven Trailer Park outside of Easton, Md.

"We were sitting on the porch . . . and I heard this whoosh noise and by the time I looked up there was this green ice all over the yard -- it looked just like a Kool-Aid snowball," Andrews said yesterday.

Andrews summoned the Maryland State Police. Cpl. Thursby F. Cooper Jr. responded, armed with a coffee can that he used to collect samples.

Cooper called in the Civil Defense authorities to check the sample with a Geiger counter to make sure it was not radioactive. He later turned to Lutz, a full-time dispatcher for the state Department of Transportation and part-time investigator of bizarre phenomena from UFOs to spontaneous human combustion.

Lutz is having a sample of the ice tested today by a University of Maryland geophysicist. He discounted the FAA theory, since no plane was in sight when the ice fell. He hypothesized that the chunk was an ice meteor, a stone or mineral that gathers so much ice in the stratosphere that a frozen chunk survives the fiery plunge to Earth.

But, according to Farrar's more mundane explanation, the chunk probably formed because of an outside leak in the holding tank used to store lavatory refuse in airplanes. The leaked liquid freezes at high altitudes.

Meanwhile, Cooper is hoping the dirty green fluid sitting in a mayonnaise jar near his desk will prove to be from outer space, although he conceded the liquid does have "quite an odor."