Saw a fast moving light that perfomed an instantanious 90 degree turn and disappeared shortly thereafter.

I was going to my car to leave for work at the hospital. As usual at night, I looked up to the stars for a minute. I noted a light coming from my left moving fast. The light continued until it was approximately overhead or slightly to my right. It then did an 90 degree turn to its left and continued until in disappeared a couple of seconds later.
Witness indicates that the date of the incident is approximate.  PD