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then and now

the corrie years

UTV, 7.30pm We relive yet more golden moments from Cornonation Street's archives. Tonight's programme looks at how real-world events helped shape some memorable storylines. There's the high drama when Tonya Battersby, Roy Cropper, Spider Nugent and Emily Bishop joined a 1997 eco protest. And what about when Ken and Deidre (left) exchanged vows the same week as Prince Charles and Lady Diana wed in 1981?

secret patterns

the code

BBC2, 9pm Dr Marcus du Sautoy searches for natural patterns, beginning with the columns of the Giant's Causeway and moving on to everything from honeycombs to soap bubbles, claiming such formations are part of a hidden code that governs the world. He also applies the theory to mountains, clouds and trees.

old habits die hard

operation transformation: six months & counting

RTE1, 8pm Kathryn Thomas revisits two battle-of-the-bulge volunteers from last season's show. How did Emily Pigott and Rachel Walker fare with their calorie-countdown plan once the cameras stopped rolling? The first of this new three-part catch-up series should make for good viewing.

final furlong

stars go racing

RTE1, 8.30pm Trainer Willie McCreery saddles up with weather woman Jean Byrne to take on trainer Joanna Morgan and hotelier Francis Brennan. Joanna faces some hurdles dealing with Francis whose manner is not best suited to the down-and-dirty world of equestrian sports.