Hi, guys. I have a 03 Taurus SES with 50k. There is a noticeable humming noise suddenly coming under the hood last saturday. It seems to be from my alternator, which becomes louder when I gave more gas. (I havent got a chance to let the professional check yet, but I am 80% sure about this.)
Could the alternator or battery suddenly go dead? Is this a sign of death of the alternator or could it be other problems?
Before I could fix it this weekend, I have to drive this car

on highway for 600 miles, is it safe to do so?
Thanks a lot,