The spacecraft that carried young Kal-El to Earth was composed of a womb-like, egg-shaped chamber inside a main ship body resembling the pentagon. The Kryptonian symbol for air is an infinity symbol rotated 90 degrees (resembling a figure 8) inside the Kryptonian pentagon. This symbol also represents the letter "S" in the Kryptonian/Earth-English alphabet. The House of El originally took this as their symbol and it eventually evolved with the insignia inside the pentagon resembling the Earth-English alphabet's "S."