GrandCanyon 37K Ft.

Grand Canyon Dec. 31, 1973 - Nikon F2, 55 Micro, Kodachrome, from 37,000 feet, through

the window of a brand new 747.

pretty darn good for an airliner grab.

Very cool! Forgive me if this is a stupid question, but what causes those white rectangular shapes on the ground?

The rectangular shapes are man-made areas (fields, farms, etc.) which have had a dusting of snow and wind; the white rectangles are the spots where the snow has become stuck - probably inside furrows in the earth or where it clings to a bit of crop-stubble.