I have an engineering background and a pilot's license. I know a bit about meteorology. So I know that it's nothing more than some air, nearly saturated with water vapor, meeting and mixing with other air. Maybe it's cooler so the vapor condenses. Or it's dryer so the water evaporates. But the intricate interplay between the small air masses provided the most beautiful dance of light and cloud and sky.
In minutes, the emerging whisp grew to a dense ball of white, getting tugged and stretched until, for a brief moment, I glimpsed a turtle. Her head stretched out from her shell racing with the wind past my backyard deck vantage point. But soon she was stretched beyond turtle form. What had appeared as turtle shell rolled over in the breeze to reveal a widening gap. The turtle shell quickly expanded and became a hollow egg shell. The expansion continued like the growing sphere of gas and plasma expelled from a nova. Soon the shell was nothing more than wisps of cloud evaporating back to vapor. And then it was gone.
In a few minutes and about a half mile of drift, it appeared, grew, changed, and disappeared. And I may be the only one who knows it ever existed.