I went to bed around 1:30 A.M. on September 13, 2015. While I was in bed, I was checking the messages on my phone when I heard strange whistling. I assumed it was my sister, who was asleep in the room across from me, and thought nothing of it. I then fell asleep. At 6:00 A.M., roughly four and a half hours after I went to bed, I woke up to a strange high-pitched whistle. I glanced at my phone and noticed the time. My cat, who had been asleep on the windosill, woke and stood up from his spot very quickly. The whistle continued for approximately five to ten seconds before cutting off abruptly. As soon as it finished, dim light flashed briefly inside of my room. After it disappeared, I got out of bed and checked out the window my cat was standing in. Across the street from my house, there are a few houses lining the road with dense trees behind them. A few trees separated two houses from each other. There is a small opening in one of the trees. I looked out to where my cat was staring and I noticed there was a dull gray smudge filling the opening. There was a sliver of the gray top, a dome- like shape, over the trees as well. I grabbed my cat and ran to my sister's room to see if she had noticed the sound as well. She had fallen asleep with a pair of headphones on, which may have blocked out the sound. On my way back to my room, I noticed that my other cat was staring across the street out of the door as well. I left the cats by the door and returned to the window. The gray smudge was still there. I live on a usually very busy street, but there were no cars going by at all. I watched the spot for a very more minutes before I laid back in bed. I would have kept watching, but had to wake early for an event. When I woke again a few hours later, I noticed a few branches had fallen from the trees that the object at been behind. I asked my sister if she had been whistling before bed and she said that she hadn't, she had fallen asleep before me. She didn't recount anything about a whistle or such, and I have not heard anything from the neighbors.