Shocking soft green lights floating in my yard.

I was up late reading in my kitchen. We lived on a secluded acre of land among pine and aspen. My husband had gone to bed. When I got up for a bowl of cereal, & closing the refrigerator door, I looked up and saw 3 green lights in middle of window. Our secluded house only needed tie-back window drapes. I kept looking around the room to see if lights could be a reflection. Our only neighbor’s house, 2 blocks across the street, was dark.
I finally decided I couldn’t figure it out and went back to reading. I had barely sat down when I got very curious. I went back to window. Lights still hovering. I put my face up to window. Lights immediately went out. At almost same instant, most horrible sound came from our schnauzer, literally scared to death, trying to bark. He wouldn’t leave throw rug, 3 ft from screen door. He was jumping up and down, looking up at the screen. Les and I decided lights were flying saucer and why lights so small. When waking up, Les asked what terrible sound was, saying it was the most god awful sound he ever heard.
We shocked at great difference in intelligence. Saucer flew over flat roof in less than a second.