Hi All,
Possibly even a satellite,like the Space Station,etc,
Often seen as a flash,for a brief period.
I often see these when using Binoculars,with their wider FOV.
There are many others,which cause the odd flash,as well.
Look up the heavens above page,for times,etc,and heaps of other info.
http://www.heavens-above.com/
Regards.
John