Saw what appeared to be a large round ball in the sky that became elongated

My boss and I both saw what appeared to be a large black ball floating rant high in the sky the nothing of Jimmy 5th. We called our other two co workers to come over to witness what we were seeing. We all watched it change shape multiple times and go from right to left covering 30 or 40 miles in just a few minutes. Witnessed a military refueling plane fly past the object and seemed like they didn't notice it, but it was good for size comparison. The object was at least as big as a large car, if not bigger.