I was standing on the third floor balcony of my military barracks at Fort Irwin while a Corporal in the 11th Armored Calvary Regiment, looking towards NASA / JPL Research facility Goldstone. There was a smoke trail that raised up from the ground into the sky to a cloud. In the cloud was a bright light, like the sun (sun was setting in another direction). The smoke and cloud slowly changed colors from blue, to green, to red, to purple. The bright light / trail / cloud slowly faded over a 1 - 2 hour period.