I'd strongly recommend anyone doing this to wear (or at least carry in a pocket) a head-mounted torch in any case, even if you don't plan on using it at all. There are small ones that don't cost a lot and are really lightweight, and you don't need a lot of light if your eyes are accomodated to darkness anyway. A headlamp is absolutely invaluable when unexpected problems arise, like that one time I found a groaning person at the riverbank in moonless darkness or the one time I lost my way a little bit in the mountains, or the one time someones dog got scared and hid somewhere in the bushes and wouldn't return on its own. Hands-free light is just really really good to have.