Bright light traveled from North to South, decended as if to land, approached landing strip--disappeared.At 21:10 (dusk) on 7/18/99 my husband and myself observed a bright light resembling that of a Boing 737 traveling from North to south at an altitude of aprox. 1500'. We could not see a craft or hear engine noise of a craft.also there were no red or blue lights observable on the wirngs. We were traveling north on Pierce Rd.by the airport at this time. The light fluctuated from dim to bright a number of times then made a 180 degree turn while decending toward the south end of the runway. We pulled into the parking lot to watch it land....there was nothing on the runway, no noise of an engine and no activity anywhere. I called the Union County airport today to inquire of any flights that might have landed at this hour. The reply was that the airport closes at 7:00 pm and that there was no activity there that they would have known of.