Fast, Color-changing Light Observed

Date: May 20, 2009
Exact Time: 2212 (10:12 p.m.)
Location: Breckenridge, TX.
I was just stepping outside to set up my reflecting telescope (Meade digital electronic), when I noticed a commercial jetliner to my south, heading west at cruising altitude. In an instant, a bright light appeared 10 to 12 degrees above the southern horizon, heading west below the passenger jet. I saw the object for about 2 seconds and then it was gone, having traveled approximately 45 degrees Southeast to Southwest. It could have traveled farther but my vision was partially block by an outbuilding when I first observed it.
The strangest thing about the sighting, was that during the time I observed the object it changed from red, to green, to white. When it turned white it seemed to expand and then just disappeared like turning off a light switch. From my vantage point, the unknown object was somewhat larger than a grain of rice at arms length but very bright, as if it radiated a constant light (did not blink, flash or strobe).
I've witnessed hundreds, if not thousands of meteors but have never seen one with such a low, straight trajectory, nor one that changed colors like that. It is possible I suppose, that if it were a meteor the color changes could be due to a composite of iron, copper and "dirty ice", however I have never personally seen one like that. There was nothing being ejected and there was no tail on the object. It left no trail.
Note of possible interest: the object appeared to be over, or near the county airport (4 miles SSW of my location), which has recently been quite active and hosts an aviation museum. It could have been closer, or farther away but I had no sure way to gauge the distance.
The sighting happened so quickly, that I did not have time to observe the object in greater detail. It is possible that someone in the jet, or someone traveling North/South on Hwy 183 witnessed the brightly lit object before it disappeared.