Red Pulsing Orb/Light over San Antonio, TX

On 12 Dec., 2017, at approximately 1850 hrs, my family and I witnessed a pulsing red light hovering over San Antonio.  It appeared to be floating over Kelly AFB, now Port San Antonio.  It gradually moved into position, then remained stationary for approx. 3 minutes.   No sound, and there were multiple a/c in the sky.  It did not appear that the other airborne craft were circling the object per se, it just looked as though they were in the traffic pattern for SA Int’l Airport.  
The orb gradually disappeared by departing away from us to the east, as we were viewing from an elevated position to the west.  It remained perfectly still.  Not a helicopter, not a drone.  All witnesses (5) are ex-military two of which are private pilots.