Uran is Astro's cybernetic sister; a superhuman android with a naive, tomboyish personality. Constructed by Dr. Elefun as a "gift" for Astro, Uran is an extremely mischievous little girl who constantly lands her older brother in trouble. While lacking Astro's weaponry and propulsion systems, she is extremely powerful (50,000 horsepower), regularly accompanying Astro Boy on various missions (or attempting to). Like Astro, she is fully capable of experiencing human emotions although she is somewhat immature, by being naughty or disobedient.
In the original black and white tv series, Uran first appeared in Episode 25 (The Strange Birthday Present) using the name Astro Girl in the US. In the manga, the original series in other countries and the later 1980's color tv series, she is identified as Uran. She was renamed Zoran in the 2000 anime series and the 2003 game Astro Boy: Omega Factor.