This past winter, neighbors overlooking Slauson’s athletic field observed some strange doings: once a week, an illuminated disc appeared, flying over a makeshift airfield for sixty to ninety minutes at a time.

The apparent close encounter was an after-dark game of Ultimate. Teams wearing color-coded headlamps pursued a glowing disc illuminated by an LED with fiber-optic strands. Orange cones lit by Maglite flashlights marked the perimeter of the playing field, whose surface changed with the weather. “Fresh powder is nice,” observed Jeremy, a regular, one night after a February snowfall. “You can lay out for the disc and not get hurt when you hit the ground.” The following week the snow had melted to a crunchy cardboard consistency, but the players were undaunted.

In the dark, “it’s a little harder to judge where people are going, making it harder to lead them with the disc,” said Jeremy, adding that “depth perception on the lit-up disc is always interesting, too.” Kevin Schnell, who bought the equipment, is proud that “we haven’t had any injuries.” What finally ended the season was not the rigors of the game but lack of darkness: as the days lengthened in March, the game went on hiatus till next fall.