how she had photographed everything , including the mapping console with its one , tiny blinking light in the middle of north america , and then , on her computer back in longyearbyen , had transposed a longitude and latitude grid over her image to find the precise location of the blinking light-41 degrees , 47 minutes , 54.1475 seconds north and 87 degrees , 35 minutes , 41.7095 seconds west , south kimbark avenue between 53rd and 54th streets , chicago .