On 01/09/2019 at approximately 1350h central time, i walked out of my garage door to smoke a cigarette. my garage door opens facing west. i lit my cigarette and had been smoking for approximately two minutes when i spotted what i initially thought was a commercial aircraft flying towards my house which sits within the flight path of general mitchell international airport in the village of mukwonago, wi. as an aviation / astronautics / astronomy enthusiast, i enjoy spotting and identifying commercial and military aircraft, so i focused on this object, patting my leg to see if i had my cellphone on me so i could record what i was seeing, but unfortunately i had left it in my bedroom upstairs. i quickly realized that the object was not a helicopter or airplane and i had never seen anything else like this before. it appeared to be a whiteish pearlescent / translucent colored, slightly elongated sphere shape with a pulsating / strangely swirling white pearl interior light. its overall size and altitude were difficult to judge with no prior frame of reference for what i was observing, but i estimated its size at approximately 50-75 feet long by 30-50ft wide at between 6,000-10,000ft in altitude and looked to be about the size of a marble held at arms length. i was in shock that i was finally seeing something i could not logically explain after watching the sky day and night for most of my life. normally, even things that i spotted at night that struck me as strange could be explained within a day. this object was visible to me for about a minute before i lost sight of it over my house. the object revealed itself to have no wings, no visible source of propulsion, no faa lights, no visible markings, no discharge or exhaust of any visible kind, and no visible control surfaces or windows. there was a strange whiteish light that appeared to be swirling around and pulsating at different rates of speed. it almost appeared to have a doppler-like effect. as the object was coming towards me, the pulsating seemed to get faster, then it slowed down as the object flew over and continued east towards the airport and lake michigan. when i lost the object over my house, i dropped my cigarette and ran inside the house past my mother and outside onto the patio in the back yard but i was unable to reacquire sight of the object. i’m unaware if gen. mitchell saw anything on primary or secondary radar. i would really like to know what this object was and where it came from.