Population density on the Big Island of Hawaii is 19 people per square kilometer (area: 10,430 square kilometers, population: 194,190).
For comparison, Metropolitan Tokyo has roughly one-fifth the area of the Big Island and a much higher population density of about 6,270 people per square kilometer (population: 13,730,000). In addition to this exceptionally low population density, Hawaii’s astronomical community is blessed by strong cooperation among the people of the island to minimize light pollution. This combination of sparse population and low light pollution makes the Big Island exceptionally advantageous for astronomy.