Will it not simply create a blue colored hole in the sky for the duration the jet engine is turning and then when the engine is turned off the hole will soon tu

Will it not simply create a blue colored hole in the sky for the duration the jet engine is turning and then when the engine is turned off the hole will soon turn grey again ? Assuming they fire the engine during daytime. I hope they do it in the day time as that will be simply awesome and better due to the possibility of sonic boom (from the gaseous fluid in the jet exhaust going near supersonic) or the noise otherwise will prevent people from sleeping within a couple mile radius.