What happened
Paul Moran's "The Mystery of the Texas Ghost Light" in Coronet (July 1957) first described hovering, bouncing balls of light near Marfa. The Ellison story says he saw a flickering light in Paisano Pass in 1883 and took it for an Apache campfire. His 1937 memoir does not mention it, and the story reached print through relatives. In May 2004 the University of Texas at Dallas Society of Physics Students found the lights matched car headlights on U.S. 67, and a 2009 American Journal of Physics study agreed, adding small fires.