THE documentaries Apollo 13: The Untold Story and Moonwalkers: The Men Of Apollo (World, 9.35pm) were originally due to be shown two weeks ago, but were delayed. We can put men on the moon - or in the case of Apollo 13, not put men on the moon - but we can't get our ducks in line with television schedules. The untold story of Apollo 13 is not so much the untold story, rather it's the bits they didn't have time to fit in the film. The contents of this documentary are mostly included in Jim Lovell's book, upon which the film was based. One thing not mentioned in the film - and touched on only briefly in the book - is that the stricken Apollo 13 had plutonium on board. NASA had intended that Lovell leave behind scientific equipment on the moon which would need power to keep it going. Electricity sockets being hard to come by on the lunar surface, they gave him a handy-sized container of plutonium. Had Lovell ever made it to the moon the plutonium would have gone with him and posed no threat to Earth. Apollo 13's unscheduled return threw a spanner in the works. The US Government was adamant the plutonium could not be brought back and asked NASA to come up with a plan for getting rid of it. This NASA did - by jettisoning it in the lunar excursion module, which was programmed to land in the ocean off the coast of New Zealand. SOME films just should not have been made. Iron Eagle (Pearl, 9.30pm) is one of them. The preposterous plot is bad enough, but its jingoistic ethics and dubious ideals are too much for a sane man to bear. It's not boring, just stupid, but was nevertheless followed by two sequels. It's a dum-dum comic book film, about an 18-year-old (Jason Gedrick) who commandeers an F-16 fighter jet and flies to the Middle East (playing rock music on his Walkman all the way) in order to save his dad, who's been taken prisoner. IT is tradition that science fiction series have their own fan clubs. The X-Files (Pearl, 8.30pm) does. Members call themselves the X-Philes and can be found lurking on the Internet. So does Alien Nation (STAR Plus, 10pm), which is set in Los Angeles in the near future and centres on Slags, an affectionate term for aliens who try to assimilate into Earth society after their spaceship crash-lands in the desert. Time Trax (Pearl, 1am) is missing out on all this, because it has no fan club, despite the presence of Selma (Elizabeth Alexander), a hologram with great lips. THE version you will see of Red Dust (TDM CHannel 2, 8.45pm) is the computer-coloured version, giving everyone that surreal pink glow. It looks better in black and white, but who are we to stop progress? Jean Harlow proves she has a fine comic touch in this robust romance of Indochina rubber worker Clark Gable, his floozie gal (Harlow) and visiting Mary Astor, who is married to Gene Raymond, but falls for Gable instead. In black and white or colour it's fine entertainment, with a tart script and interesting settings. FILMS on Cable Movie Channel: The Golden Corps (9am). A huge amount of gold has been stolen from a team of men transporting it across China. They suspect it has been spirited away to Hong Kong and arrive in the territory looking for the culprit - and the booty. Starring Xu Zhong, Wu Ma and Li Zixiong. The Other Half (9pm). Hong Kong comedy from 1990, directed by Chiang Ka-chun. Two married couples see life get complicated when they engage in a bit of wife-swapping. Things get even harder when one of the women discovers she is pregnant. Carol Cheng, Eric Tsang and Mark Cheng are the stars. Yojimbo (11pm). The latest in Cable's excellent Akira Kurosawa season is the director's boisterous, exuberant comedy-satire about violence, with Toshiro Mifune as an unemployed samurai, a sword for hire, who wanders into a town divided by two rival merchants quarrelling over a gambling concession.