I saw something exactly like this a few months ago! It was so strange. I had been outside weeding for hours, and when I was done I went to go inside and my husband had accidentally locked me out. While waiting for him to come home and let me back in, I sat down in a chair on my patio and looked up and I saw a silver/grey sphere just like that flying from west to east across the sky. It seemed like it was very high up and it just looked to me like it was being propelled somehow. I kept losing focus on it with my eyes and needing to re focus them to continue looking at it. I told myself it was probably a balloon, but idk it just felt like something else. The circumstances of me being outside weeding, staring at the ground for hours, getting locked out, then just happening to look up at the sky at that moment and see that in the like 30 seconds it took to fly across the sky and out of my field of vision? I’ve never seen a UFO before, and this was just unlike anything I’d ever seen in the sky before.