Gas boiler pilot light won't stay lit

We have an old Thorn EMI Apollo gas boiler that's worked fine up until yesteday evening, when the pilot light went out for no apparent reason. I've tried to light it several times but it just goes out again.

My knowledge of the inner workings of boilers is limited to say the least, so I'd be grateful if anybody could offer up any help as to why this might be happening.

Thanks in advance for any help.

Probably "just" a thermocouple, but your boiler isn't a kitten, it'll bite your head off. Call in a corgi engineer.

Thanks for the advice Chris.