Squat 'arrow' shaped craft seen over Wootton on the Isle of Wight

Walking across the recreation ground, my friend and I saw a light rising in the distance. As it did so, it appeared to 'jettison' a stream of falling lights as it rose. This caught our attention, and we stopped to watch this strange object.
 The main light continued to move, and over the next minute of watching it became clear it was coming our way. I'm not sure how we realised this, time having dimmed my recollection. But, we were aware of a shape that blocked out the stars as it moved (it was a very clear night), and in the event the craft moved directly over us. Its shape was like a triangle added to a square - so a 'squat arrow' shape. The triangle point was the 'nose'. It was completely silent. As it passed over us it was larger than a hand-span at arm's length. Once we were viewing the flat rear of the craft as it moved away from us, three large round white 'engine ports' were clearly visible.
 As it slowly flew out over the Solent, we saw a commercial aircraft (probably a passenger jet) flying across the sky also. It was in the same 'general' airspace, so I've wondered whether anything else was reported.
 It's all so long now that I can't be sure of the precise year it happened, let alone the date. But I know I was about 15, it was a cold, clear dark night, and I remember hurrying home with my friend to tell my mum and dad. They weren't particularly interested. I wrote it all down, but the notes have long since disappeared. I often wonder whether other reports might describe something similar. But I am also interested by my own lack of drive to research more.
Witness indicates that the date of the incident is approximate.  PD