I was outside in back yard with my dog. I first noticed the object simply because I always watch the sky for hawks and aircraft. It was definately not a blimp. To thin; longer than a Boeing 767-300; no lower "navigation basket/viewing" area; extremely long, thin, cigar shape.No wings; no tail section; no sound and maintained level altitude and moderately slow speed. Headed towards Sarnia, Ontario but when it went into a white cloud, it did not come out of the other side of the cloud.It was silver and the sunlight reflected off of it.I truly believe it was a UFO......simply because of other past observations I've experienced.I was tempted to wave, but decided differently because I do not wish to perhaps encourage any problems in the future with them for myself. I just wished that they would be able to help stop all of the wars and chaos in our world and let things be better for us on our planet. I also wondered where they were from, were they enjoying the scenery as they flew along, and where were they headed?I lost sight of it when it flew into a small cloud and it did not fly out of the cloud on the other side. I did not have a camera and have previously experienced (when I lived in Sarnia before) that if I could take any pictures, then a day or so later, at least 2 men in black suits come and confiscate the pictures and/or film from me as they did before.They communicate with aliens and know where to confiscate pics obviously.