Night Light of Blackhawk (California) from space (United States) Src. Average luminocity for 10x10km area is 25.6003% and for 50x50km: 36.4346%.
Square area 10x10 km:
 1.36%
 1.19%
 0%
 1.36%
 4.25%
 14.46%
 6.97%
 3.4%
 12.07%
 19.39%
 35.54%Square area 50x50 km:
 6.33%
 6.39%
 1.76%
 4.96%
 6.2%
 7.75%
 6.16%
 4.65%
 11.83%
 17.73%
 26.24%Clear (daylight) street map image can be seen on geolist.org.
Map coordinates:
38° 22' 26.7" North, 122° 36' 39.1" West
37° 49' 14.7" North, 121° 54' 27.9" West
37° 15' 47.7" North, 121° 12' 16.6" West
Some cities around Blackhawk sort by population:
• San Ramon
		7.7 km =4.8 mi, 
233°
• Walnut Creek
		16.8 km =10.4 mi, 
304°
• Dublin
		13.4 km =8.3 mi, 
190°
• Danville
		8.1 km =5 mi, 
270°
• Alamo
		11.4 km =7.1 mi, 
286°
• Clayton
		13.6 km =8.5 mi, 
349°
• Waldon
		17.5 km =10.9 mi, 
312°
• Saranap
		16.4 km =10.2 mi, 
295°
Sources (retrieved 2019-11-25):
» Earth at Night: Flat Maps 2012, 2016