A grey soundless object zoomed thru the night sky. It seemed pretty close and it whent faster than any plane.On March my dad asked me if I want to go to the car-wash with him. I approved and told him I'll be waiting outside. Unusually, the sky was very clear above Ljubljana so I just gazed at the stars. I saw a rectangle shape flying thru the sky. It had no lights, nor did it make a sound. It seemed close (I tought it was around 200-300 metres, but no one can tell actually). It zoomed thru the sky faster than a plane but slow enough so that I could see it for 7-10sec. I started hicking up and got really scared cause I'm a great beliver. I assure you that I did not make any of this up and that I am perfectly normal and do not have a mental condition.