Fluorescent green sphere travelling very fast along the baseline of local hills near Greymouth.

On dusk one evening while talking to my family I looked out the window and saw a round very bright fluorescent green light travelling at a constant speed along the baseline of some local hills - above and behind some houses to the north.  It was too low and in the wrong place to ever have been a conventional aircraft and it was travelling very fast. 
By the time I alerted my family to look as it was such a strange thing to see, it was gone.  
The next day there was a report in the local newspaper that a person in a nearby town - Cobden- had reported seeing a similar light, however between Cobden (to the south) and my town is a range of hills; and what I saw could not have been seen by that person unless it had travelled around or over these hills.
Source of report indicates that date of the event is approximate.  PD