Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Mystery Fossil Found in Antarctica is Giant Egg, Scientists Say VOA News Researchers say they have determined a mystery fossil discovered in Antarctica in 2011 is a large egg, possibly laid by an ancient aquatic reptile. Science publication Inverse reports that since the fossil was discovered, researchers referred to it as the "thing," because they could not classify it. They compared it to a deflated American football -- oval in shape, about 28 centimeters long and 18 centimeters wide. In a study published Wednesday in the science journal Nature, researchers from the University of Texas at Austin used microscopic analysis to confirm that the fossil is indeed an ancient egg. .