Single, fast moving bright green light/orb, low and silent.

I was sitting outside on my back deck, enjoying the clear night sky. Lots of stars and constellations visible. We live 3 miles from Gaston Municipal Airport so we are used to the small plane air traffic in the area. Planes flying the landing flight path takes them directly over the cul de sac where our house is located.
We are very familiar with how a small plane is lit up at night, with multiple different colored lights on the wings and fuselage. What my wife and I watched this night was not one of these planes.
From the position I was sitting on my upper deck, I was facing the back of my house, looking up over the roofline. I turned my head to the left, looking towards my neighbors house and through the trees (still devoid of leaves at this time) I saw a single, solid bright green light. (Orb is the only descriptive word that seems to fit.) Also, it was too low for the usual plane. These 2 items are what caught my attention first. It was also moving fast in a straight line, heading from SW to NE. I yelled to my wife to come out and look which she did very quickly. We watched together as it flew until the back of the house obscured it from view. We ran to the opposite side of the deck so we could see around the other side of our house and we could see it again, continuing in it’s straight line off into the distance until we could no longer see it due to trees and houses. We’ve lived here almost 20 years, close to the airport, and have never seen anything like it. Estimated altitude 150 to 200 feet and speed of about 200-300 mph. Totally silent.