Night Light of Castel from space (Guernsey) Src. Average luminocity for 10x10km area is 3.2311% and for 50x50km: 0.1708%.
Square area 10x10 km:
 0%
 0.98%
 0.14%
 0%
 0%
 0.56%
 1.26%
 1.54%
 1.68%
 0%
 93.84%Square area 50x50 km:
 0%
 0.04%
 0.01%
 0.02%
 0.01%
 0.04%
 0.05%
 0.06%
 0.07%
 0%
 99.71%Clear (daylight) street map image can be seen on geolist.org.
Map coordinates:
49° 55' 20.6" North, 3° 18' 11.8" West
49° 28' 3.3" North, 2° 36' 0.5" West
49° 0' 30.6" North, 1° 53' 49.3" West
Some cities around Castel sort by population:
• Saint Helier, JE
		47.5 km =29.5 mi, 
130°
• Saint Peter Port
		4.8 km =3 mi, 
100°
• St Anne
		39.5 km =24.5 mi, 
45°
• Saint Sampson
		5.8 km =3.6 mi, 
71°
• Torteval
		5.2 km =3.2 mi, 
223°
• St Martin
		4.7 km =2.9 mi, 
135°
• Saint Andrew
		3 km =1.9 mi, 
151°
• Saint Saviour
		2.8 km =1.7 mi, 
245°
Sources (retrieved 2019-11-25):
» Earth at Night: Flat Maps 2012, 2016