UPSC 2013 CDS 2 GK Paper

The Circle of Illumination divides Earth into two hemispheres knownas: Day and Night. The circle of illumination is the line thatseparates the Earth to create equal parts of day and night. It passesthrough the poles and allows the entire Earth to have an equalamount of time spent during the daylight and nighttime .The circle ofillumination always bisects the equator (0 degree latitude).