of at least 30 "Fireball XL" vessels (an XL30 is mentioned in the episode "The Firefighters"). The ship has a "gravity activator" for artificial gravity and consists of two detachable sections. A winged nose cone dubbed Fireball Junior houses the cockpit and serves as a self-contained short take-off and vertical landing craft for exploring planets. The main, larger section contains a navigation bay, laboratory, workshops, lounge and crew quarters, together with the rocket motors that enable interstellar travel. On arrival at an alien world, the main section usually remains in orbit while Fireball Junior travels down to the surface. The WSP is based at Space City, located on an unnamed island in the South Pacific Ocean. The organisation is headed by Commander Zero, assisted by Lieutenant Ninety. For unspecified reasons, the city's 25-storey, T-shaped control tower is seen to rotate (in one episode, a character accidentally causes it to turn fast enough for those inside to suffer vertigo). XL5s deep-space patrols are missions of three months' duration; between missions, the ship is on call at Space City. The ship blasts off from a mile-long launch rail ending in a 40-degree incline. On its return to Space City, it lands vertically in a horizontal attitude using underside-mounted retro-rockets. Until the episode "Faster Than Light", XL5 travels through space at sub-light speeds. Its rocket motors, powered by a "nutomic" reactor, provide a maximum safe speed of "Space Velocity 7", allowing the ship to reach the outlying star systems of charted space within a few months. The crew do not wear spacesuits outside the ship: instead, they take "oxygen pills" to survive the vacuum while using thruster packs to manoeuvre. The ship's "neutroni" radio enables virtually instantaneous communication with Space City and other space vessels over vast distances. Episodes Characters Regular Colonel Steve Zodiac (voiced by Paul Maxwell): the pilot and commanding officer of Fireball XL5. In the episode "Space City Special" he is declared "Astronaut of the Year". Doctor Venus (voiced by Sylvia Anderson): a doctor of space medicine, of French origin. Zodiac personally selected her to be a member of the XL5 crew. According to the episode "The Last of the Zanadus", Venus has served on the ship for five years. Professor Matthew "Matt" Matic (voiced by David Graham): XL5s engineer, navigator and science officer. Robert the Robot (voiced by an uncredited Gerry Anderson through an artificial larynx): the co-pilot of