In like 2003 my sister and I were driving home through a big stretch of country and we saw a fucking huge ass disc with lights around the edge jet up from the tree line and disappear into the clouds at an extreme speed. I don't think it was aliens but damn I sure will always wonder wtf that thing was.
One time i was going to my high school dorm and when i was looking out the window i saw a light that was moving back and forth in a U-shape. It was way too far to see anything other than the light. When i got off the train it was still there and half an hour later it was still there. Wanted to ask my roommate for his phone (It was about 2005 and camera phones were a luxury in Eastern Europe then) but he got there ours later and by that time it was gone.
Could've been a balloon or a helicopter too, but it made no noise and i think balloons aren't allowed to fly in the dark? Also it made no noise as far as i can remember.