Myself and a friend,had been working on a mutual friends garden during the day.We stayed over to complete the work the next day.Since both of us smoked,we went to the side kitchen door,and sat on the wall,that surrounds the back steps to the house,and kitchen door.I was talking to my friend Tony,When i looked up and over his shoulder,i could see in the night sky a complete circular,swirling mass of what i first thought was a cloud.This thing was massive,I asked my m8,if he could see this,to which he answered YES.For some reason he was reluctant to look at it directly.As i observed this circular mass,i was aware that their was no clouds in the sky,apart from this ring,yet to the left of me stars were visible,but nothing could be seen in front of me apart from this ring.The mass was swirling in both a clockwise,and anti clockwise direction,and the outer edge was being pulled and curled inwards as if forming a wall within itself holding the circle completely in place.The centre of this ring was Black,as Black can be,nothing else was visible directly in front of me.I watched this swirling mass for what seemed ages,but was 15-20 seconds,when suddenly,this thing just blinked out and disappeared completely.I was in absolute awe of what i had just seen,and was trying to talk to my m8,when suddenly this from nowhere,this thing burst open again.It seemed to open from a single spot in space and create in a mini seconds this same circular swirling mass of cloud and light.I noticed that it had moved a small distance away from us,but still in the same height in the sky.I could'nt understand how it was generating its own mass of light,and illuminating the circular cloud formation of this swirling circular mass,again i observed this for about 10-15 seconds,when it blinked out.Each time it disappeared,the stars that were visble before its appearance came into view,but again ,disappeared when this thing burst open.all that was visible in the sky directly in front of us was this giant ring of clouded light,and its dark centre.I observed this happen about 5 times in total,each time slowly going away from us,until we both went back in the house about 15-20 mins later.At no time could i see anything entering,or exiting out of the centre of this mass,nor did i have the common sense to go get my cell phone to try and video this,i was just awe struck by the event.My friend has'nt for whatever reason discussed this with me,or made any comment on this nights events.My friends house backs onto wooded farmland,in a semi rural area,street lighting,and village pollution lighting is minimal at the back of the house,tho this is on the flight path to glasgow airport.I presume that anyone else who may have been around and out that night may have seen a similair event to me,but as yet i have'nt heard anyone discuss this.Yours SincerelyMr Eric Cunningham