HUNTSVILLE, Alabama - Whatever Tuesday's Redstone radar blob was, it was unlike anything most professional radar watchers have ever seen. Speculation has centered on secret defense testing at Redstone Arsenal, and the University of Alabama in Huntsville has said it has found feathery pieces of fiberglass near the area. All this has led Huntsville scientists to be discreet in their public speculation so far in deference to national security. But they are shedding more light on an event that exploded on radar like a thunderstorm, spread nearly 10 miles wide and a mile high, and lasted for nine hours - all while being virtually invisible to the naked eye.

Matt Havin and Dr. Michael Lawton, meteorologists at Huntsville's Baron Services Inc., watched the blob on multiple radars at their operations center in Cummings Research Park. Company founder Bob Baron, a former television meteorologist, invented and developed the first tornado-tracking technology for television forecasters, and his company works with TV stations and companies nationwide. In an interview Wednesday about the blob, Havin first listed "what we know it's not"

1. A thunderstorm or rain. There was no rain in the area.

2. Bats, birds or insects. "Bats or birds tend to have a (radar) signature that expands rapidly," Havin said. "We've seen signatures like this with insects before, but usually it's not this size or this duration."

3. The 1,000 ladybugs released by the Huntsville Botanical Garden to fight aphids.

4. Typical small fragments of military chaff (radar countermeasures). Generally, Havin said, military chaff is carried by upper-level winds in bands. "Typically chaff signatures are released by aircraft," Lawton said. "That's why they have a long, sort of elongated signature. This did not look like that."

5. Dust. "It wasn't that," Havin said, "otherwise we'd see signatures like that in the Plains all the time at harvest time, and we don't."

7. Smoke. "Out of any of the potential causes," Havin said, "smoke is what this most closely looks like if it wasn't going to be a severe thunderstorm. But to have a signature of this size and strength, you'd have to go from nothing to an extreme forest fire almost instantaneously. And you'd see a lot of smoke, which we did not."

6-8. Radiation, jamming (which has an on-off signature), or a bad Huntsville Utilities substation.

Here's what the two meteorlogists can say about "whatever it was," in Havin's words.

1. It was suspended in the air for about nine hours, started on the north side of Redstone Arsenal just after 1:30 p.m. and ended around 11 p.m. (CDT). "That's a very long time for something to be hanging around," Havin said.

2. All the radar signatures "had to occur between the surface of the ground and about 5,500 feet above the ground above Redstone Arsenal."

3. It was greater than 8-10 miles in diameter for "most of the duration."

4. "It was pluming." The source was apparently sending up either multiple or almost continual releases of "whatever it was from very low elevation or from the ground. It shot up from the surface or a very low level," Havin said.

5. It showed up on different radar frequencies, including the S-band radar used by the National Weather Service and the C-band radar used by one local TV station.

Neither Havin nor Lawton, a Phd research meteorologist, has ever seen anything like this on radar. But despite that, what did people at Baron Services see when they went outside Tuesday to look? "It wasn't anything obvious," Havin said.

(Follow me on Twitter @leeroop)



This story was updated Wednesday at 10 a.m. CDT to change the spelling of the word "discreet"