One gray triangular aircraft the size of a large jet with a white light at each point, and a red light in the middle

October, 28 202119:15 in Enfield NH     My wife and I were sitting in our hot tub on the back deck observing the stars when my wife exclaimed "what is that!".  I looked over my shoulder and saw one triangular aircraft.  It had a white light at each point, and a red light in the middle.  I estimate it was flying in a E to W direction.  I estimate that if you were to use the lengthof a large jet to make the 3 sides of a triangle, that would be about the size of what we observed.   It was moving about the same speed as a jet, but was low enough that I should have been able to hear it, and I could not.  We could both see the gray outline of it, and it looked like a large triangle.  What are your thoughts?   Thank you