A huge bright light descends from the sky then shoots off at an angle

My mother and I was driving home one night in our Rambler.  I was about 10 y/o. Traveling west on Jefferson Highway.  The area was mostly woods then. 
We saw a huge bright light descending from the sky to our right.  We thought it was a helicopter, but no sound or wind was emitted.  Mom actually stopped and pulled over to get a better look and I remember her getting out of the car.  
She remembers that the light abruptly shot off and away at an angle that helicopters did not perform.  
We are both nurses now and still wonder about this incident.
Date is approximate.  One of three reports from same source, who appears to us to be a credible witness.  PD