A clock is a good idea. I'm getting towards the end of one which syncs itself to the MSF time standard (available in the UK). I expect something similar is available in other countries. You can contact the National Physics Laboratory to get the info on the signal.

You can use one of the timer interrupts of the 8052 to decode the time signal, and another to multiplex an LED display.

What is the project for? University degree course final year? I've been there.

Have fun!