Dark coloured round discWe saw an object that transversed across the sky (roughly overhead) it was rather large and low (like an aircraft coming in for landing. I know it was low because I could see the raised top of the object when it got some distance away). The object didn't appear to have any wings. The object did NOT make a sound, as I would have expected an aircraft to do. It was dark coloured/black. It appeared to have light coloured concentric rings around the circumference of the underside. It was moving at an apparent constant speed. I told my friend to keep watching it while I ran into my house to fetch my binoculars. When I returned it was too far to make out anything new... although it could be seen on the horizon.The object was over the horizon after around 2 minuets. It was a clear afternoon, dropping cold and there was very little cloud. We were not under the influence of any type of drug (alcohol, e.t.c.) I am an intelligent person, 19 years of age. I am not saying that this thing we saw in the sky was a flying craft controlled by aliens, nor am I saying it’s some secret military aircraft of some type simply because don’t know what it was. I am just reporting this because I found it unusual and was a little shaken by it.