I got home from work and walked out my back door for a smoke. i sat on the stairs and looked up and was stunned to see a large dark cigar object. i was shocked and ran inside to get my iphone to film it. when i came back to stairs it had darted to high altitude very rapidly. with my eyes i could still see the dark colour and the elongated shape but in video it only shows as blinking lights that dart about a specific location. it was there for about 15mins. the flashing lights to me were random and more akin to a reflective object reflecting the light of the sun. the altitude was now significantly higher then regular commercial airline. i took video of a plane to show the normal height for comparative reasons.