Shetland earthquake?

[treesparrow]

I wonder if this incident concerned an incoming or exploding rock from space. A loud bang and rattling windows were reported.
How many reported lower strength earthquakes might in fact be due to meteorite impact ?

http://www.independent.co.uk/news/uk/home-news/earthquake-hits-shetland-islands-1379828.html

This is also an unusual part of the world for earthquake activity.