I was around eight or nine years old. We lived on a farm on the edge of dartmoor in devon england. The event took place at around 8 to 10pm maybe later as it was a dark but clear and stary night. we had come out of the house and were standing in our garden I looked up and noticed the black diamond shaped craft it was travelling slowly about the same speed as a low earth orbiting satellite incidently the two lights were the size of a satellite there was no sound as i remember it the size of the craft would be equal to the size and length of my thumb if held up in the air. We all witnessed it, my mother, her boyfriend and my brother. The craft was travelling from north to south in a straight line it seemed to be very high up and very large. Blacker than the night sky and blocking out the light from the stars above it as it moved accros the sky. The shape was equal in its geometry being slightly longer in its length. The light on the back point was slightly brighter than the light on the front point. On questioning my mother on the subject recently, she remembers a light going up and joining the craft but I do not remember this happening. I remember the object disapearing in the distance my memory of the incadent is vivid but not of what we were doing before or after. This all took place in 1978/9 and this is the first time we have talked of it outside of the family.