Last night's viewing - Mission to Mars: a Horizon Special, BBC2; Simply Italian, Channel 4

Terrestrially speaking, the Olympics are the best show in town when it comes to a nerve-shredding discrepancy between preparation time and actual performance. If you haven't heard a commentator say it already, you definitely will sometime in the next few weeks: "Four long years of hard work and sacrifice," they'll mutter solemnly. "All down to the next 30 seconds." But that unequal face-off between imagined achievement and actual result is dwarfed by the one-shot-only fixture covered in Mission to Mars: a Horizon Special.

Operation Curiosity has been in the planning for eight years, has cost $2.5bn and relies for its success on a complicated set of devices that will have to work perfectly the first time they're used in earnest. And since it takes 14 minutes for a radio signal to get from Earth to Mars, there's nothing anyone back here can do if something out there goes wrong. "It's going to be the longest roller-coaster ride they've ever taken," said one of the mission team about his control-room colleagues.

Horizon cheated just a little in its presentation of the hazards. Two-thirds of all missions to Mars have ended in failure, it said, which is true but doesn't quite allow for improvement over time. Of the first 15 missions to Mars, for example, 11 failed in some way. Of the most recent 15, only five have gone wrong, Nasa having learnt an important lesson from the scaldingly embarrassing occasion, in 1999, when Climate Orbiter crashed on to the surface of the planet because two separate teams hadn't agreed on whether they were using metric or imperial measures. But even if the odds are a little better than this film suggested, you're still looking at a colossal bet in terms of intellectual and financial investment. The Mars rover the Curiosity team are trying to put on the surface is five times heavier than any previously used and has to be lowered the final few metres to the surface by a cable dangling from a rocket-propelled platform. "Even the team that's working it sometimes think it's crazy," confessed one scientist, frustratingly forgetting to explain why it isn't.

Once on the surface, many millions of miles from the nearest Kwik Fit franchise, the rover will have to trundle around without breaking down, looking for interesting outcrops and occasionally pouring samples of grit into its own innards (can't see any problems arising there). Unsurprisingly, the mission team have begun to think of this semi-autonomous machine as an entity with a life of its own: "It's very much akin to having a kid in college," said one engineer. "We raised her, we taught her everything she knows, we gave her all the gear that she needs to investigate her new world, but now she's gone." And, it turns out, she's going to have to queue up to use the dorm phone to call home – Nasa only having one antenna big enough to receive the messages from Mars. They fire the starting pistol on the final descent on 6 August and Horizon's engrossing film will surely have added to the numbers of those anxiously waiting to find out if they get to the finish line.

I would like a commemorative medal to be struck for Michela Chiappa's father. His daughter is the presenter of Channel 4's new cookery show, Simply Italian, and so contractually bound to insist that nothing ever goes wrong in the kitchen. "I mean, it can't get any easier than that," she said, after whipping up her own homemade lasagne verdi. But when she asked her dad for a verdict on the finished dish – in one of those breezy, just-cooking-for-friends sequences – he defied all known precedent by replying: "It's very good... but it's missing a little salt." That man is a hero and if he doesn't feature in every episode I'll want to know why.