Triangular object hovering fairly low to the ground before disappearing out of sight. Witnessed by 5 people

It was about 3 in the morning, my sister went out to smoke a cigarette. She messaged me and said there's something hovering in the sky, I ran outside and there it was. It was triangular and fairly low to the ground. It sat in one position before moving above the tree line and out of sight. I was playing xbox with my friends at the time and told them I think I just saw a UFO. They asked me about a dozen times what I was talking about and it took me about 5 minutes to respond because I just couldn't get the words out. It was almost impossible to explain something like that. The next day I woke up to a message from a friend who lives about 3 minutes away from me, he said his mother and both of his sisters saw exactly what I saw along with a description which was the same as mine. I'm glad someone else saw it other than my sister and I or I'd think I'm going crazy.