Very bright light hovering over Cook Strait, New Zealand, shooting away at speed.On the 26th of May, 2016, I was driving from the town of Kaikoura to Blenheim on the north-east coast of New Zealand’s South Island. Heading north on Hwy 1, approaching Lake Grassmere at about 19:45, I noticed a very bright light in the night sky over the range of hills just north of the lake. The light seemed to be farther out behind the hills, likely over the Cook Strait. Being somewhat colour blind, I am not sure of the colour of the light, could have been red or orange.I pulled over on the highway (41°44'05.0"S 174°07'43.2"E) to get a better look. It was suspicious as it was much brighter than any stars in the sky or aircraft for that matter. At first, I wondered if it was the aircraft landing light on a plane taking off from Wellington airport, but it did not move up or down, just stationary.The light sat stationary over the hills for about 5-minutes until precisely 19:49. It then dimmed to about 25% of its original luminescence, then moved off to the North at a rate of speed I would suggest being 2-3-times faster than normal air traffic in the area.Wellington airport is quite busy at this time, however the airport runway runs North-South, and was northeast to my position with aircraft taking off or landing in North or south direction. The light was to my north-northeast, several degrees north of the light pollution given off by the city. Checking some flight apps, I was not able to find a plane that would have been in that position at the time of sighting.It is worth mentioning that 20-min before the sighting, a 4.3 magnitude earthquake was registered in the Cook Strait, in the general area where I had witnessed the light.