"murgatroid" replies BI ONLINE...oh yes...that aerial view of what had looked like a 'green alien image' upon the ground...google maps...

https://www.google.co.uk/maps/@51.5049523,-0.127612,3a,15y,58.88h,104.1t/data=!3m8!1e1!3m6!1s-eyw8PuXi-oY%2FVTzLfr6CfZI%2FAAAAAAAAaDo%2FD7x2BgcG2GsrT5oiJ4XQEsMt8tCQxGGcgCLIB!2e4!3e11!6s%2F%2Flh5.googleusercontent.com%2F-eyw8PuXi-oY%2FVTzLfr6CfZI%2FAAAAAAAAaDo%2FD7x2BgcG2GsrT5oiJ4XQEsMt8tCQxGGcgCLIB%2Fw203-h101-n-k-no%2F!7i10240!8i5120!6m1!1e1