Observation conditionsIt was getting darker, but the object was very visible against the clouds lighted by the setting sun. The sun was below the horizon already, with only the clouds receiving light. The weather was overcast (70% of the sky covered by clouds) with a very light breeze - maybe 1 or 2 on the Beaufort scale.There was a big tree between myself and the object, that impeded my view whilst the object passed behind it, but I observed it before and after it passed behind the tree.Object descriptionThere was only one object, black and probably best described as a diamond, though I can't give a perfect description of its shape, even after consulting myself with other witnesses. We all agree it was round shaped but presented angles. However, it wasn't so pointed as the standard diamond shape. Bar its black colour and slightly odd shape, the object presented no other features, such as lights or markings. It was also perfectly silent, with no trails of smoke whatsoever that would imply any kind of reaction propulsion. It had no wings or rotor blades either. It never changed shape, colour, and I haven't observed any aura or haze around it.The object moved bearing SW with about 100 Km/h (approx. 60 mph) at an altitude I'd appreciate somewhere between 70 and 150 meters. (200-450 ft.) The object appeared to be 6-8 meters in diameter (18-25 ft.)ConclusionsAs the object moved at a 45��� angle to my position, I was able to observe it from different perspectives, and as such I can to state that it didn't looked like any type or aircraft known to me, and I'm pretty savvy about such things. The absence of position lights, sound and features (wings or rotor blades) would also indicate that it was no civilian aircraft. I can also eliminate the hypothesis that it was a blimp or balloon due to the speed it moved at, with no wind to speak of. The clouds weren't moving either, which eliminates the possibility of wind at higher altitudes. There was silent enough for the sound of an engine to be heard, but there wasn't any. There were no other aircraft nearby and its trajectory followed none of the streets, which eliminates for me the eventuality that is was pulled from the air or from the ground. There was also no such things as a rope to be seen. The visibility was excellent, as the clouds were very bright with no sun to impede direct observation.At this point, it's an unidentified flying object for me. I'd be very glad and interested to hear another opinion(s). I'm also glad to answer any question you might have regarding this incident. As English isn't my first language, I'd be also happy to clarify any questions which may arise due to the poor wording, if applicable.Answering additional questionsThere was a second witness which will remain anonymous.1. Swimming in a pool outside our city of Munich, in a small town 50 Km to the East - Bad Aibling.2. The second witness spotted the object on the sky, just by incidentally looking in that direction3. The object looked strange enough for us both to ask "hey, what's that?!" It looked in the first second like a spheric helicopter heading directly towards me, but I very quickly realised that it can't be the cockpit of such an aircraft, and it's not heading towards me. It took me under one second to realise.4. The object was described, and it just followed a straight path.5. We merely observed the object with interest. We moved a bit around to minimise the time it was hidden by the tree. No special feelings other than I had no idea what am I looking at. We discussed the incident after we lost sight of the object.6. The object disappeared in the distance, hidden by buildings as it flew its path.