you should find "date" command.
If you use the Intel(R) IoT developer kit SD card image date should automatically be set if you do have internet access. Otherwise "timedatectl" would be the recommended command line tool there (although "date" would work as well)
Conor, was the time accurate a few months ago? How far off is it? Mhahn's suggestions for updating the time are all great ideas, but if your board looses time that is a problem.
if you don't have internet access and you don't put a battery on Galileo you will definitely loose time with every boot. The Intel IoT developer kit SD card image will at least try to save the time when hibernating and continue with that time if there is no ntp access