Glowing orbs in various places and then a sweeping light across the mountain unlike anything I've ever seen.I was fourteen, I live in Washington D.C, but I was up at our cabin in Montana with my whole family. My grandma, uncle, and I were outside looking at the stars. My uncle told us he saw a glowing light about fifteen feet in front of us. We all looked where he was pointing. For about 10 seconds ever 5 or so minutes, an extremely bright light about the shape and size of a softball would glow. It was white and extremely bright. Our cabin is pretty isolated so it is pitch dark except for the stars. After watching the glowing orb for about half an hour, I noticed there was another one in the trees to our left. We began to get a little freaked out and tried to come up with explanations, because we were all hardly ones to believe in UFOs.After watching the orb in the tree and the one in the tall grass 15 feet in front of us, we noticed one far in the distance on the top of Black Butte (the mountain in front of our cabin). At first we thought it was a star, because it was on the edge. But it was so bright and too big to be a star. At that point, it began to inch extremely slow in a straight line across the mountain.I really have no idea how to explain the next part of our sighting to you. We had been watching the orbs for give or take an hour and a half. We were frozen there, mesmerized by what was going on. All of the sudden, out of the pitch black, a bright white light swept across the side of the mountain, and across the field beneath the mountain next to our cabin. We could see everything in the light. Everything else was pitch black except for were the light was hitting, it was illuminating every tree, every blade of grass, everything in its path. I ran inside to get my dad and my grandpa, but by the time I got them to come out, everything was gone. We tried to explain what had just happened but it just sounded crazy. I know what I saw, and my uncle (33 at the time) and my grandma (64 at the time) know as well.{This was outside of Redlodge Montana, in-between Roscoe and Elk Lake, if it interests anyone}