The simple answer is that it is a moon-shaped lens flare! The flares in your image are crescent, or ellipse, shaped because the source of light was shaped like that. Had it been an ordinary day when the sun was not obstructed by the moon, the lens flares would have been circular. A lens flare is the phenomenon where light is scattered, or flared, in a camera’s lens system, often in response to a bright light.
The crescents in my Fujifilm camera photos are pale violet; the crescents in my iPhone photos are aqua blue-green.