My buddy had returned from the army for the week and we were at our friends house outside late at night around 1 a.M. it was december so the driveway was frozen, so i was sort of moon walking away from them towards his garage. on my way back towards them, staring at the sky, what looked to be a star at first caught my eye from behind a tree. after i noticed it moving, almost curving in the sky i got my friends attention and pointed it out to them. as we watch it come closer and closer, getting bigger and bigger, this what at first small, starlike shape in the distance, turned to be a tetrahedron shaped aircraft moving very slowly and very low in the sky, until it was literally over the houses of the next street over. it made little to no sound, almost like a vibration/humming noise. the two sides of the ship (2 triangles of a tetrahedron) were moving in and out of each other, giving it no consistent shape. i was able to see the only consistent fixture on the aircraft as it continued moving and it started to curve away from us just as it had curved towards us. it was a glowing, bright light in the shape of a door on the back of the ship, as if it was open and emitting light from the inside. the whole situation was very strange, and my buddy from the army at first tried to rationalize saying it was a drone that he had seen before that the government had tested, but after further questioning, and more thought of how it was moving and had no consistent shape, he too was convinced it was nothing he had seen before.