This blue wave-type shape is part of an evening photo sequence from Aug. 17, 2020 which includes yellow, pink, and fire-colored images. Several photos in this project, such as the pink and blue photo below, were taken on Aug. 19, 2020 with a walking stick.
I used a walking stick to create the figure-8 hula hoop shape shown above and below. For the above image, the figure-8 horizontal extent is approximately 15-20 feet, and the vertical extent is approximately 7-10 feet. [Aug. 19, 2020]